CN111939306A

CN111939306A - Antibacterial dressing and application thereof

Info

Publication number: CN111939306A
Application number: CN202010850749.0A
Authority: CN
Inventors: 龚祖光; 蔡坤川; 蒋锐
Original assignee: Shanghai New Valve Medical Devices Co ltd; Jiangsu Newvalue Medical Products Co ltd
Current assignee: Shanghai New Valve Medical Devices Co ltd; Jiangsu Newvalue Medical Products Co ltd
Priority date: 2020-08-21
Filing date: 2020-08-21
Publication date: 2020-11-17

Abstract

The invention provides an antibacterial dressing and application thereof, wherein the antibacterial dressing comprises at least one layer of antibacterial liquid-absorbing fiber non-woven fabric and at least one layer of liquid-absorbing fiber non-woven fabric, one side of the antibacterial liquid-absorbing fiber non-woven fabric layer is used for pasting a wound, the liquid-absorbing fibers and the antibacterial liquid-absorbing fibers have high liquid-absorbing amount, and the polyhexamethylene biguanide in the antibacterial liquid-absorbing fibers has good slow-release effect and can achieve the optimal antibacterial effect.

Description

Antibacterial dressing and application thereof

Technical Field

The invention relates to an antibacterial dressing and application thereof.

Background

Clinically, chronic wounds are often characterized by much seepage, susceptibility to infection and difficulty in healing, because the surface of the chronic wound is a warm and humid environment, pathogens such as staphylococcus aureus, candida albicans and escherichia coli are rapidly propagated on the wound, and in order to control the bacterial propagation of the wound and prevent the wound infection, various antibacterial materials are considered to be added into a large number of medical dressings, namely, antibacterial agents are added into the dressings, so that the bacteria propagation in the dressings can be effectively inhibited, the wound infection is reduced, the wound is protected, the infection is reduced, secretions are absorbed, the body is kept warm, and the wound healing is promoted.

The fibers in the current antibacterial dressing have no antibacterial property per se, and as mentioned in patent publication No. CN100379395C, "the invention discloses that PHMB can be used on a cellulose fabric alone to cover a wound", so that an antibacterial agent needs to be applied to the antibacterial dressing made of the fibers; furthermore, the antibacterial agent in the antibacterial dressing in the prior art has poor slow release effect, for example, the PHMB antibacterial product with the trade name of Kerlix of mednly corporation, namely poly hexamethylene biguanide salt yarn type dressing (hereinafter referred to as Kerlix dressing), the antibacterial agent is distributed in the fiber, the release amount is limited in 7 days, the liquid absorption is poor, and the effect is not ideal particularly when the dressing is applied to the treatment of chronic healing wounds such as burn wounds, bedsores and the like which are easily infected and have more effusion.

Disclosure of Invention

In order to solve the problems, the invention provides an antibacterial dressing which comprises at least one layer of antibacterial liquid-absorbing fiber non-woven fabric and at least one layer of liquid-absorbing fiber non-woven fabric, wherein one side of the antibacterial liquid-absorbing fiber non-woven fabric layer is used for attaching a wound, the liquid-absorbing fibers and the antibacterial liquid-absorbing fibers have high liquid-absorbing amount, and the polyhexamethylene biguanide (also called PHMB) in the antibacterial liquid-absorbing fibers has good slow-release effect and can achieve the optimal antibacterial effect.

The invention is realized by the following technical scheme:

an antibacterial dressing comprises at least one layer of antibacterial liquid-absorbing fiber non-woven fabric and at least one layer of liquid-absorbing fiber non-woven fabric, wherein one side of the antibacterial liquid-absorbing fiber non-woven fabric layer is used for applying a wound,

the liquid-absorbent fiber in the liquid-absorbent fiber nonwoven fabric comprises a polymer represented by the following formula:

wherein the content of the first and second substances,

r is at least 1 selected from the group consisting of-OH, -ONa, -OK, -OCa;

m, n and p represent the number percentage of the corresponding repeating units in the formula, respectively, and satisfy the following formulas 1 and 2:

m + n + p ═ 1 formula 1,

p/(m + n + p) ═ 0.05-0.30 formula 2;

the liquid-absorbent fiber has a total degree of substitution Ds, a center degree of substitution Do, and an edge degree of substitution Dx, which satisfy the following formulas 3 and 4:

ds is 0.09-0.8, formula 3,

Do/Dx is 0 to 0.7, formula 4,

wherein Ds represents the total degree of substitution of the fiber, Do represents the degree of substitution of the polymer at the center point of the cross-section of the fiber, and Dx represents the degree of substitution of the polymer at the edge of the cross-section of the fiber, and D is m/(m + n + p),

the antibacterial liquid absorption fiber in the antibacterial liquid absorption fiber non-woven fabric comprises the liquid absorption fiber and an antibacterial agent, wherein the antibacterial agent comprises polyhexamethylene biguanide, and the polyhexamethylene biguanide is distributed in the depth range of 0-1 mu m from outside to inside on the surface layer of the liquid absorption fiber.

One side of the non-woven fabric layer made of the antibacterial imbibing fibers of the antibacterial dressing is used for being pasted on a wound, the polyhexamethylene biguanide of the antibacterial imbibing fibers is distributed on the surface layer of the antibacterial imbibing fibers, the quick release of the polyhexamethylene biguanide is facilitated, and the polyhexamethylene biguanide and carboxyl groups of imbibing fiber molecules are fixed on the surface of the imbibing fibers through ionic interaction, so that the slow release of the antibacterial agent effect can be realized, the antibacterial aging is prolonged, the 7-day release amount is increased day by day, and the wound healing is facilitated. In addition, at least one layer of non-woven fabric is made of liquid absorption fibers, so that the liquid absorption of the dressing is improved while the dressing is antibacterial.

Drawings

FIG. 1 is a physical image of the antimicrobial liquid-absorbing fiber of the present invention under a non-contact submicron infrared Raman simultaneous measurement system;

FIG. 2A shows that one of the antibacterial liquid-absorbing fibers of the present invention forms an infrared image 1660cm in a non-contact submicron infrared Raman synchronous measurement system^-1/1580cm^-1Analyzing the graph (the dotted line is an auxiliary line added in the later period and outlines the fiber); in FIG. 2A, the arrow portion with a flat tail represents 1660cm^-1Peak intensity of signal and 1580cm^-1The ratio of the peak intensities of the signals is high, so that the arrow part with a flat tail comes from PHMB (because PHMB is 1660cm in the infrared spectrum^-1And 1580cm^-1Signal peak intensity equivalent); while the dovetail arrow part represents 1660cm^-1Peak intensity of signal and 1580cm^-1The ratio of the intensity of the signal peaks is low, therefore, the dovetail arrow part comes from the liquid-absorbing fiber (because the liquid-absorbing fiber is 1580cm in the infrared spectrum^-1The signal peak intensity is obviously higher than 1660cm^-1Intensity of signal peak), wherein the ordinate on the right side in fig. 2A is 1660cm^-1Peak intensity of signal and 1580cm^-1The ratio of the signal peak intensities;

FIG. 2B is a 1660cm infrared imaging of the antibacterial liquid-absorbing fiber in FIG. 2A in a non-contact submicron infrared Raman synchronous measurement system^-1/1580cm^-1A real object diagram (the dotted line is an auxiliary line added at the later stage and outlines the fibers);

FIG. 3A shows a 1660cm IR imaging of another fiber cross section of the invention in a non-contact submicron IR Raman synchronous measurement system^-1/1580cm^-1Analyzing the graph (the left lower corner insert graph is a corresponding object graph);

FIG. 3B is a 1660cm IR imaging of the other side of the fiber in a non-contact submicron IR Raman synchronous measurement system^-1/1580cm^-1Analysis chart (the left lower corner insert chart is the corresponding object chart), and the ordinate on the right side in FIG. 3B is 1660cm^-1Peak intensity of signal and 1580cm^-1The ratio of the signal peak intensities;

FIG. 4A is a 1064cm infrared image of the cross section of cotton fiber of Kerlix dressing of the present invention in a non-contact submicron infrared Raman synchronous measurement system^-1Infrared imaging plot of (from cotton fibers), where the right ordinate of fig. 4A is the intensity of the infrared signal;

FIG. 4B is an infrared imaging 1580cm of the cross section of cotton fiber of Kerlix dressing of the invention in a non-contact submicron infrared Raman synchronous measurement system^-1Infrared imaging plot at (from PHMB), right ordinate of fig. 4B is intensity of infrared signal;

FIG. 4C is a graph of the overlay process analysis of FIGS. 4A and 4B, with the right ordinate of FIG. 4C showing the intensity of the IR signal;

fig. 5 is a bar graph of polyhexamethylene biguanide release by antimicrobial dressings of the present invention versus Kerlix dressings over 7 days.

Detailed Description

The aspects and effects of the present invention will be described in further detail below with reference to preferred embodiments and examples, but the present invention is not limited to the following embodiments or examples.

In the case of ordinary chitin fibers, when the degree of substitution is controlled to control the liquid absorption performance of the fibers, there arises a problem that the degree of substitution is too low, the liquid absorption amount of the fibers is insufficient, the degree of substitution is too high, and the liquid absorption amount is significantly increased, but the fiber morphology is difficult to maintain, that is, the fibers are dissolved or dispersed by the absorbed liquid.

For example, when the fibers in the following table are immersed in physiological saline and the liquid absorption amounts are measured as multiples of the dry weight of the fibers, the liquid absorption amounts are small when the substitution degree is low, the practical value is not large, and when the substitution degree is too large, the fibers excessively absorb liquid, so that the original structure is lost, and the originally absorbed water returns to the environment, and the liquid absorption amounts cannot be measured.

Degree of substitution	0.02	0.1	0.7
				Liquid absorption amount (times)	0.5	1.0	Can not measure
Liquid-absorbing form	Holding	Holding	Can not maintain

In view of the above, the present inventors have surprisingly found that, when the degree of substitution in the central portion of the fiber is reduced to maintain the fiber in a satisfactory form, the structure of the outer portion of the fiber is attached to the skeleton by intermolecular forces, and the fiber is not easily detached and dispersed, and the basic fiber form can be maintained even after a large amount of liquid absorption, and thus the present invention has been completed.

The liquid-absorbent fibers of the present invention comprise a polymer represented by the following structural formula:

wherein the content of the first and second substances,

r is at least 1 selected from the group consisting of-OH, -ONa, -OK, -OCa;

m + n + p ═ 1 formula 1,

p/(m + n + p) ═ 0.05-0.30 formula 2;

the lower limit is preferably 0.10 or more, more preferably 0.15 or more, and the upper limit is more preferably 0.25 or less, more preferably 0.20 or less.

If the p value is too large, the liquid absorption of the fibers is lowered. If the P value is too small, the fibers are dissolved after contacting with the liquid, and the morphology is difficult to maintain.

ds is 0.09-0.8, formula 3,

Do/Dx is 0 to 0.7, formula 4,

wherein Ds represents the total substitution degree of the fiber, Do represents the substitution degree of the polymer at the center point of the cross section of the fiber, and Dx represents the substitution degree of the polymer at the edge of the cross section of the fiber, and the substitution degree D is m/(m + n + p);

the lower limit of Ds is preferably 0.2 or more, more preferably 0.3 or more, still more preferably 0.4 or more, and the upper limit is preferably 0.7 or less, more preferably 0.6 or less, still more preferably 0.5 or less.

If the Ds value is too large, the maintenance of the fiber morphology is not facilitated, and therefore the Ds value is not suitable for the surface film substrate; if the amount is too small, the liquid absorption of the fibers is reduced, and the problem of a small amount of carrier liquid for the mask base cannot be solved.

The lower limit of Do/Dx is more preferably 0.05 or more, still more preferably 0.1 or more, yet more preferably 0.15 or more, and the upper limit is more preferably 0.6 or less, still more preferably 0.5 or less, yet more preferably 0.4 or less.

If Do/Dx is too large, the fibers are dissolved when contacting liquid, the basic shapes of the fibers cannot be maintained, so that the fibers are swollen when contacting water in the production of the spunlace nonwoven fabric, the film base material becomes hard after drying, the uniformity of the film base material is also influenced, and the film base material is not suitable for users with facial injuries because the film base material is not easy to remove from wounds. When the substitution degree is too small, the specific value of the expansion rate of the fiber diameter/the expansion rate of the fiber length is not enough, and when the liquid absorption amount of the fiber is reduced, the fiber is easy to adhere to the wound and is not beneficial to removing from the wound, so that the problem that the carrying liquid amount of the mask base material is small cannot be solved, and the mask base material is not suitable for a user with a wound on the face.

The smaller the value of Do, the better the center form of the fiber is maintained, and the more easily the center portion functions as a skeleton, and for example, Do may be 0.02 or less, 0.05 or less, 0.1 or less, 0.2 or less, 0.25 or less, 0.3 or less, or 0.35 or less.

The center point of the fiber in the invention is the geometric center of the cross section when the cross section of the fiber is in a regular pattern, and is the geometric center of gravity of the cross section when the cross section of the fiber is in an irregular pattern.

The fiber edge in the present invention refers to the position on the cross section of the fiber farthest from the center point of the fiber.

The shape of the fiber cross section is not particularly limited, for example, circular, elliptical, clover, triangular, polygonal, etc., but circular or elliptical is preferable from the viewpoint of uniform modification, and circular is most preferable.

The diameter of the cross section of the fiber is not particularly limited, but is preferably 1 to 1000. mu.m, the lower limit is more preferably 5 μm or more, more preferably 10 μm or more, still more preferably 15 μm or more, and the upper limit is more preferably 500 μm or less, still more preferably 200 μm or less, still more preferably 100 μm or less.

The fiber diameter is mainly related to the application, and for example, the fiber diameter may be thick when applied to a mask base material or the like for external use or to a site with a large amount of bleeding or exudate.

The length of the fiber is not particularly limited, but is preferably 1 to 10cm, the lower limit is more preferably 2cm or more, more preferably 3cm or more, still more preferably 5cm or more, and the upper limit is more preferably 9cm or less, still more preferably 8cm or less, still more preferably 7cm or less.

If the length of the fiber is too short, the cutting or the preparation of the fabric is not facilitated, and if the length of the fiber is too long, the fiber is easy to bend when forming the fabric, the opening and carding of the fiber are not facilitated, and the subsequent processing of the fabric or the non-woven fabric is difficult.

The polymer used in the fiber has 3 kinds of repeating units having different structures as shown in the above figure, but the molecular formula represents only the kind of the repeating unit contained in the polymer, and the arrangement order of the repeating units may be arbitrary. In other words, as long as the ratio of the repeating units meets the requirement of the present invention, the arrangement order does not affect the object of the present invention.

The viscosity average molecular weight of the polymer of the present invention is preferably 5 to 1000 ten thousand, the lower limit is preferably 10 ten thousand or more, more preferably 20 ten thousand or more, more preferably 50 ten thousand or more, more preferably 100 ten thousand or more, and the upper limit is preferably 900 ten thousand or less, more preferably 800 ten thousand or less, more preferably 700 ten thousand or less, more preferably 600 ten thousand or less.

When the viscosity-average molecular weight is too large, the molecular chain is in a curled state, and the reactive groups on the molecular chain are easily wrapped, so that the reaction is not facilitated, and the total substitution degree is too low. When the viscosity-average molecular weight is too small, the molecular chain is short, the reactive group is easy to expose, and the reactive reagent and the hydrolytic reagent are easier to penetrate through the gaps of the molecular chain and have the effect on the molecular chain, so that the total substitution degree is greatly increased, the difference between the center point and the edge substitution degree of the cross section of the fiber is small, the fiber is dissolved after contacting with liquid, the fiber form cannot be maintained, and the service performance of the fiber is influenced.

The group R of the polymer species is at least one selected from the group consisting of-OH, -ONa, OK, and-OCa.

The fibers preferably have a good liquid-absorbing capacity, and the amount of liquid absorbed is preferably 2 times or more, more preferably 5 times or more, still more preferably 10 times or more, based on the weight (dry weight) of the fibers themselves, based on the absorption of physiological saline (0.9% sodium chloride solution), and the upper limit is not particularly limited. Preferably 20 times or less.

More preferably, the fibers are as thick as possible without lengthening upon imbibition swelling, i.e., the fiber diameter expansion ratio is much larger than the fiber length expansion ratio, preferably the fiber diameter expansion ratio/fiber length expansion ratio is more than 5 times, more preferably more than 10 times, more preferably more than 20 times, and more preferably more than 30 times. The larger the ratio, the more favorable the retention of the fiber morphology, i.e., the swelling upon imbibition, without being completely dissolved or dispersed by the absorbed liquid.

The fiber diameter of the present invention means a diameter of a circle when the cross section of the fiber is circular, and a line connecting two points located at the farthest distance from each other on the edge of the cross section of the fiber when the cross section of the fiber is not circular.

The expansion ratio of the fiber length means:

(Length after fiber imbibition-Length before fiber imbibition)/Length before fiber imbibition X100%

The expansion ratio of the fiber diameter means:

(diameter after fiber imbibition-diameter before fiber imbibition)/diameter before fiber imbibition X100%

Wherein, the weight content of the polyhexamethylene biguanide in the liquid absorption fiber is 1000-5000ppm, the antibacterial effect is poor below 1000ppm, and the biocompatibility is poor above 5000ppm, such as the stimulation effect on the skin.

Preferably, the weight content of polyhexamethylene biguanide in the liquid-absorbent fiber is 3000-5000 ppm. The higher the content of polyhexamethylene biguanide in the liquid absorbing fiber is, the more the amount of the released polyhexamethylene biguanide applied to the antibacterial dressing is increased, and the slow release effect is better, so that the better antibacterial effect can be realized.

Preferably, the recurring unit of polyhexamethylene biguanide is

Wherein, the polymerization degree of the polyhexamethylene biguanide is preferably 12 to 16; because polyhexamethylene biguanide and the liquid absorption fiber can ionize carboxyl anions in water, and the polyhexamethylene biguanide has guanidino cations, the polyhexamethylene biguanide and the liquid absorption fiber can be combined together through the acting force of ionic bonds, if the repeating unit is less than the range, the combined polyhexamethylene biguanide on the liquid absorption fiber can be reduced, and the antibacterial effect is reduced; if the repeating unit is larger than the range, the solubility of polyhexamethylene biguanide in a mixed solution of water and alcohol is reduced, which also results in a reduction in the binding of polyhexamethylene biguanide to the liquid-absorbent fiber and a reduction in the antibacterial effect. Thus, the present invention provides an optimal range of recurring units of polyhexamethylene biguanide.

[ method for producing antibacterial liquid-absorbing fiber ]

Preparing a polyhexamethylene biguanide mixed solution by using a polyhexamethylene biguanide aqueous solution and a solvent, wherein the ratio of water to the solvent in the polyhexamethylene biguanide mixed solution is as follows: 1:3-1:9, wherein the solvent is one of methanol, ethanol or acetone, and the PHMB content in the final mixed solution is 1% -2.5% (w/v).

After the synthetic reaction of the liquid absorption fiber is completed, washing the liquid absorption fiber by using an antibacterial agent mixed solution to obtain the antibacterial liquid absorption fiber, and then dehydrating and drying the antibacterial liquid absorption fiber.

[ antibacterial dressing ]

The non-woven fabrics of the antibacterial dressing are respectively 1 or more of needle-punched non-woven fabrics, spunlace non-woven fabrics, woven fabrics or non-woven fabrics, yarns, loosely combined multi-layer non-woven fabrics or loose fiber groups made of antibacterial liquid-absorbing fibers; and any 1 or more of needle punched non-woven fabric, spunlaced non-woven fabric, woven or non-woven fabric, yarn, loosely bonded multi-layer non-woven fabric, or loose fiber mass made of liquid-absorbent fibers.

When woven or nonwoven fabric is used, the grammage is preferably 1 to 500gsm, the lower limit is more preferably 5gsm, more preferably 20gsm, more preferably 50gsm, and the upper limit is more preferably 450gsm, more preferably 400gsm, more preferably 350 gsm.

The absorption capacity of the antibacterial liquid absorption material to physiological saline containing 0.9% of sodium chloride is 5-40 times of the dry weight of the antibacterial liquid absorption material. In the antibacterial liquid-absorbent material to be molded, in addition to the liquid absorption of the fibers themselves, the fiber internal space sealed by the expansion of the fibers arranged in parallel can store a large amount of water. Thus, the shaped antimicrobial liquid absorbent material can achieve better liquid absorption properties than the fibers themselves.

The method of forming the fibers is not particularly limited, and the fibers can be formed into various forms such as woven fabrics and nonwoven fabrics by a known method.

In some embodiments, the antimicrobial dressing is composed of at least three layers of non-woven fabrics, wherein two layers of non-woven fabrics positioned at two sides of the outer side of the antimicrobial dressing are both made of the antimicrobial liquid-absorbing fiber, and at least one layer of non-woven fabric positioned at the middle layer of the antimicrobial dressing is made of the liquid-absorbing fiber. By adopting the technical scheme, the two sides of the antibacterial dressing can be used for covering the wound without distinguishing the front side and the back side, and the use is convenient. When the antibacterial dressing is used for a surface wound, one side of the antibacterial dressing used for covering the wound can be used for inhibiting bacteria at the wound and repairing the wound; while the other side of the antimicrobial dressing may be used to block external bacteria from entering the antimicrobial dressing. In addition, the antibacterial dressing is also suitable for cavity type wounds, namely the antibacterial dressing can be used for covering both sides of the wound to inhibit bacteria at the wound and repair the wound at the same time. In addition, the non-woven fabric of the middle layer is also made of liquid absorption fibers, so that the liquid absorption amount of the antibacterial dressing can be further increased.

Preferably, the grammage of the antimicrobial dressing is between 60 and 250 gsm. Within a reasonable gram weight range, the antibacterial dressing has better antibacterial performance and liquid absorption performance.

[ antibacterial application ]

The antibacterial dressing can be applied to the field of biological medicines.

Examples

1. Method for determining parameters of fiber material

1.1 measurement of m, n, p

The type of the instrument used for the measurement: model AMX600M NMR spectrometer manufactured by Bruker of Germany

The desired content relationship can be calculated from the measured values, for example, m/(m + n + p), p/(m + n + p) equivalents.

The specific operation method comprises dissolving fiber in 1% CD₃D of COOD₂In O, the characteristic group of each repeating unit is determined (for example, m corresponds to-NCH in its repeating unit)₂-、-OCH₂-; p for-NCOCH in its repeating unit₃-) and calculating the ratio of each repeating unit according to the ratio of the area size of the proton peak area.

1.2 determination of the degree of substitution at a certain point on the fiber cross-section (e.g.a point on the center or on the edge)

Soaking the fiber in water/ethanol (v/v-20/80) solution containing 30% (w/v) KOH at 60 ℃ for 5 hours, taking out the fiber, repeatedly washing the fiber with 80% (v/v) ethanol water solution for 8 times, drying the fiber at 40 ℃ for 24 hours after removing washing liquid, quenching the dried fiber in liquid nitrogen, testing the content of K at the center point of the cross section of the fiber and the content of K at the edge of the fiber by an energy spectrometer (EDS), calculating the substitution degree of each point according to the contents, and taking the ratio of the content of K at the center point of the cross section of the fiber to the content of K at the edge of the fiber as the substitution degree ratio.

1.3 absorbency Performance test

1.3.1 liquid absorption

20 fibers were taken and measured for dry weight W (g) using an analytical balance. Soaking nylon cloth in 0.9% sodium chloride normal saline for 30min, taking out, drying, wrapping with the nylon cloth, and weighing W₁(g) In that respect Weighing enough physiological saline containing 0.9% sodium chloride 500 times more than 20 fibers, placing the fiber wrapped with nylon cloth therein, standing at 37 deg.C for 30min, taking out the nylon cloth bag, spin-drying, and weighing as W₂(g) In that respect The absorption capacity of the individual fibers is (W)₂-W₁)/W。

1.3.2 expansion ratio of fiber diameter to Length

And taking out the spun fiber, fixing the spun fiber on a glass sheet, and measuring the diameter and the length of the imbibed fiber under a microscope. Additionally, dry fibers were fixed on a glass slide and their diameters and lengths were measured under a microscope.

The measurement results of the above data are summarized in tables 1 to 4 below.

Method for measuring viscosity average molecular weight: the measurement is carried out by the Ubbelohde viscosity method. Taking a certain amount of fiber, dissolving in 0.1mol · L^-1CH₃COOH-0.2mol·L^-1The viscosity-average molecular weight of NaCl was calculated by measuring the flow-out time of NaCl in a constant-temperature water bath at (25. + -. 0.05). degree.C.by means of an Ubbelohde viscometer.

See examples 1-6 for methods of making liquid absorbent fibers:

example 1

Weighing 5g of chitin fiber with the length of 6cm and the p/(M + n + p) of 0.25, dispersing the chitin fiber in 50mL of isopropanol, adding 2.54g of acrylic acid-2-hydroxyethyl ester, oscillating the mixture evenly at room temperature, reacting the mixture for 48h in a thermostatic water bath at the temperature of 50 ℃, separating the reacted chitin fiber from the reaction mixed solution, washing the reaction mixed solution for 2 times by using 80% (v/v) methanol aqueous solution, taking out the fiber, drying the fiber by spinning, dispersing the fiber in 80% (v/v) methanol aqueous solution, dropwise adding 30% (w/v) potassium hydroxide aqueous solution, adjusting the pH of the methanol and potassium hydroxide aqueous solution mixed solution to 11.0, soaking the mixture for 1h, separating the soaked fiber from the mixed solution, washing the fiber for 3 times by using 80% (v/v) methanol aqueous solution, dehydrating the fiber, and drying the fiber at the temperature of 40 ℃ to obtain a viscosity-average molecular weight (M eta) of 300 ten thousand, A liquid-absorbent fiber having an amount substitution degree of acryloyl group-containing total substances of 0.17.

Dissolving the imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-proton peak area in (a), whereby the content of R2-OK in the substituted acryloyl group was calculated to be 22%; then R1 is-OCH₂CH₂The OH content was 78%.

Example 2

5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.10 is weighed and dispersed in 50mL of isopropanol, adding 7.09g of acrylic acid-2-hydroxypropyl ester, oscillating uniformly at room temperature, reacting in constant temperature water bath at 70 deg.C for 48 hr, separating chitin fiber from reaction mixture, washing with 80% (v/v) methanol water solution for 2 times, taking out fiber, drying, dispersing in 80% (v/v) methanol water solution, dripping 30% (w/v) potassium hydroxide aqueous solution, adjusting pH of the mixed solution of methanol and potassium hydroxide aqueous solution to 11.0, soaking for 1 hr, separating the soaked fiber from the mixed solution, washing with 80% (v/v) methanol water solution for 3 times, dewatering, drying at 40 ℃ gave a liquid-absorbent fiber having a viscosity average molecular weight of 300 ten thousand and a degree of substitution of the amount of the total acryloyl groups of 0.30.

Dissolving the imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-proton peak area in (a), whereby the content of R2-OK in the substituted acryloyl group was calculated to be 35%; then R1 is-OCH₂ CH₂CH₂The OH content was 65%.

Example 3

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.10, dispersing the chitin fiber in 50mL of isopropanol, adding 14.17g of acrylic acid-2-hydroxypropyl acrylate, oscillating the mixture evenly at room temperature, reacting the mixture for 48h in a constant-temperature water bath at 70 ℃, separating the reacted chitin fiber from the reaction mixed solution, washing the mixture for 2 times by using 80% (v/v) methanol aqueous solution, taking out the fiber, drying the fiber by spinning, dispersing the fiber in 80% (v/v) methanol aqueous solution, dripping 30% (w/v) potassium hydroxide aqueous solution, adjusting the pH of the methanol-potassium hydroxide aqueous solution mixed solution to 11.5, soaking the fiber for 1h, separating the soaked fiber from the mixed solution, drying the fiber by spinning, and placing the fiber in saturated CaCl₂The solution was immersed for 1 hour, and the fiber was taken out, washed 3 times with an aqueous 80% (v/v) methanol solution, dehydrated, and dried at 40 ℃ to obtain a liquid-absorbent fiber having a viscosity average molecular weight of 50 ten thousand and a degree of substitution of the amount of the total acryloyl groups of 0.49.

Dissolving the imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-peak area of protons in (a), thus calculating the content of R2 as-OCa in the substituted acryloyl group as 39%; then R1 is-OCH₂ CH₂CH₂The OH content was 61%.

Example 4

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.25, dispersing the chitin fiber in 50mL of isopropanol, adding 5.08g of acrylic acid-2-hydroxyethyl ester, oscillating uniformly at room temperature, reacting for 58h in a constant-temperature water bath at 55 ℃, separating the reacted chitin fiber from a reaction mixed solution, washing for 2 times by using an 80% (v/v) methanol aqueous solution, taking out the fiber, drying by spinning, dispersing in an 80% (v/v) methanol aqueous solution, dripping a 30% (w/v) potassium hydroxide aqueous solution, adjusting the pH of the methanol and potassium hydroxide aqueous solution mixed solution to 11.5, soaking for 1h, separating the soaked fiber from the mixed solution, drying by spinning, and placing in saturated CaCl₂The solution was immersed for 1 hour, washed with 80% (v/v) aqueous methanol solution 3 times, dehydrated, and dried at 40 ℃ to obtain a liquid-absorbent fiber having a viscosity average molecular weight of 50 ten thousand and a degree of substitution of the amount of the total acryloyl groups of 0.55.

Dissolving the imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-peak area of protons in (a), thus calculating the content of R2 as-OCa in the substituted acryloyl group as 27%; then R1 is-OCH₂ CH₂CH₂The OH content was 73%.

Example 5

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.25, dispersing the chitin fiber in 50mL of isopropanol, adding 6.30g of acrylic acid, uniformly oscillating at room temperature, reacting for 40h in a constant-temperature water bath at 70 ℃, separating the reacted chitin fiber from a reaction mixed solution, washing for 2 times by using 80% (v/v) methanol aqueous solution, taking out the fiber, drying, washing for 3 times by using 80% (v/v) methanol aqueous solution after drying, dehydrating, and drying at 40 ℃ to obtain the liquid-absorbing fiber with the viscosity-average molecular weight of 8 ten thousand and the quantity substitution degree of the total acryloyl substances of 0.75.

Dissolving the imbibing fiber in 1% CD₃D of COOD₂And O, performing nuclear magnetic hydrogen spectrum test. The results show that compared with chitin fiber raw material, the liquid absorption fiber only has two new absorption peaks with chemical shifts of 2.3 and 3.1, and the absorption peaks are assigned to-NCH₂CH₂CO-, indicating that R2 was-OH, the content was 100%, and the degree of substitution by amount of the total acryl group-derived substances was 0.75 by calculation.

Example 6

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.10, dispersing the chitin fiber in 50mL of methanol, adding 1.91g of acrylamide, uniformly oscillating at room temperature, reacting for 72h in a constant-temperature water bath at 40 ℃, separating the reacted chitin fiber from a reaction mixed solution, washing for 2 times by using an 80% (v/v) methanol aqueous solution, taking out the chitin fiber, spin-drying, soaking in a 40 ℃ saturated sodium bicarbonate solution for 1 hour, taking out the fiber, washing for 3 times by using an 80% (v/v) methanol aqueous solution, dehydrating, and drying at 40 ℃ to obtain the liquid-absorbing fiber with the viscosity-average molecular weight of 900 ten thousand and the acryloyl total substance quantity substitution degree of 0.09.

Dissolving the liquid absorption fiber in 1% diluted acetic acid, and testing by using a sodium ion meter to obtain the substituted acryloyl with the content of R2-ONa of 5%; then R1 is-NH₂The content of (A) is 95%。

Quenching the liquid absorption fiber in liquid nitrogen, and measuring the-CO-content of the center point of the cross section of the fiber and the content of the fiber edge by X-ray photoelectron spectroscopy (XPS), so as to calculate to obtain the substitution degrees of the acryloyl groups at the center point of the cross section of the fiber and the fiber edge to be 0 and 0.12 respectively.

TABLE 1 basic parameters of liquid-absorbent fibers

In the above table, the calculation process of each embodiment is as follows:

and testing the substitution degree of acryloyl groups at different sites of the cross section of the fiber by EDS, namely completely hydrolyzing the liquid absorption fiber into potassium carboxylate by using a KOH solution, completely cleaning and drying, wherein the amount of K is equal to that of carboxylate radical substances, and calculating to obtain the amount of the carboxylate radical substances by obtaining the content of K through the EDS test, thereby calculating to obtain the substitution degree of the acryloyl groups.

For example 6, since the grafted acrylamide was not hydrolyzed to generate carboxyl groups, the-CO-content thereof was obtained using XPS test to calculate the degree of substitution at different sites.

TABLE 2 absorbency Properties of the absorbent fibers

1.4PHMB content test

The principle is as follows: separating PHMB to be measured from the liquid absorption fiber by adopting a high performance liquid chromatography, detecting by using a PAD detector, comparing the obtained PHMB spectrum peak with the spectrum peak of a standard substance, and calculating the content by adopting a standard curve method.

The instrument comprises the following steps: liquid chromatograph, PAD detector

The operation method comprises the following steps: about 0.2g of the sample was cut into pieces of about 5mm by 5mm, precisely weighed, precisely added with 10mL of methanol, and placed in a 15mL ionization tube. Shaking in a constant temperature shaking table at 37 deg.C for 24 hr, and collecting the leaching solution. Filtering the leaching solution with 0.45 μm organic filter membrane, and performing liquid phase test on 1.5mL of the filtered leaching solution. 3 samples were selected for testing, each sample being tested 1 time. Methanol was used as a blank. Sampling 100 mu L of the sample under the specified chromatographic condition, recording a spectrogram, and taking the average value of the three sample tests as an experimental result.

Calculating the formula:

PHMB content C in sample_iCan be calculated according to equation (1.1):

in the formula:

C_i-the content of PHMB in the sample,%;

M_i-looking up the PHMB content in the sample leach liquor on a standard curve, with units of micrograms per milliliter (μ g/mL);

v is the volume of the leaching liquor of the sample, and the unit is milliliter (mL);

m-mass of sample in grams (g).

Preparation of antimicrobial liquid-absorbing fiber see examples 7-12, where figure 1 shows a physical image of the antimicrobial liquid-absorbing fiber under a non-contact submicron infrared raman simultaneous measurement system.

Example 7

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.25, dispersing the chitin fiber in 50mL of isopropanol, adding 2.54g of acrylic acid-2-hydroxyethyl ester, oscillating the mixture evenly at room temperature, reacting the mixture for 48h in a thermostatic water bath at 50 ℃, separating the reacted chitin fiber from the reaction mixed solution, washing the reaction mixed solution for 2 times by using an 80% (v/v) methanol aqueous solution, taking out the fiber, drying the fiber by spinning, dispersing the fiber in an 80% (v/v) methanol aqueous solution, dripping a 30% (w/v) potassium hydroxide aqueous solution, adjusting the pH of the methanol-potassium hydroxide aqueous solution mixed solution to 11.0, soaking the fiber for 1h, separating the soaked fiber from the mixed solution, washing the fiber for 1 time by using an 80% (v/v) methanol aqueous solution, washing the fiber for 1 time by using a 1% (w/v) PHMB aqueous solution, and finally washing the fiber for 1 time by using an 80% (v/v) methanol aqueous solution, washing for 2h each time, dewatering, and drying at 40 deg.C to obtain antibacterial liquid-absorbing fiber with viscosity average molecular weight (M eta) of 300 ten thousand and acryloyl group substitution degree of 0.17.

Dissolving the antibacterial imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-peak area of protons in (a), thereby calculating the content of R-OK in the substituted acryloyl group to be 22%; the balance being-OCH₂CH₂The OH content was 78%.

Shearing 0.2g of antibacterial liquid absorption fiber, leaching for 24h, taking the filtered leaching solution, performing liquid chromatography test, and calculating according to the result to obtain PHMB with the content of 1000 PPM.

Example 8

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.10, dispersing the chitin fiber in 50mL of isopropanol, adding 7.09g of acrylic acid-2-hydroxypropyl acrylate, oscillating the mixture evenly at room temperature, reacting the mixture for 48h in a thermostatic water bath at 70 ℃, separating the reacted chitin fiber from the reaction mixed solution, washing the reaction mixed solution for 2 times by using an 80% (v/v) methanol aqueous solution, taking out the fiber, drying the fiber by spinning, dispersing the fiber in an 80% (v/v) methanol aqueous solution, dropwise adding a 30% (w/v) potassium hydroxide aqueous solution, adjusting the pH of the methanol-potassium hydroxide aqueous solution mixed solution to 11.0, soaking the fiber for 1h, separating the soaked fiber from the mixed solution, washing the fiber for 1 time by using an 80% (v/v) methanol aqueous solution, washing the fiber for 1 time by using a 1% (w/v) PHMB aqueous solution, and finally washing the fiber for 1 time by using an 80% (v/v) methanol aqueous solution, washing for 3h in each washing cycle, dehydrating, and drying at 40 deg.C to obtain antibacterial liquid-absorbing fiber with viscosity average molecular weight of 300 ten thousand and acryloyl group substitution degree of 0.30.

Dissolving the antibacterial imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-proton peak area, calculated to give 35% of R-OK in the substituted acryloyl group; the balance being-OCH₂ CH₂ CH₂Of OHThe content was 65%.

Shearing 0.2g of antibacterial liquid absorption fiber, leaching for 24h, performing liquid chromatography test on the filtered leaching solution, and calculating according to the result to obtain PHMB with the content of 2600 PPM.

Example 9

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.10, dispersing the chitin fiber in 50mL of isopropanol, adding 14.17g of acrylic acid-2-hydroxypropyl acrylate, oscillating the mixture evenly at room temperature, reacting the mixture for 48h in a constant-temperature water bath at 70 ℃, separating the reacted chitin fiber from the reaction mixed solution, washing the mixture for 2 times by using 80% (v/v) methanol aqueous solution, taking out the fiber, drying the fiber by spinning, dispersing the fiber in 80% (v/v) methanol aqueous solution, dripping 30% (w/v) potassium hydroxide aqueous solution, adjusting the pH of the methanol-potassium hydroxide aqueous solution mixed solution to 11.5, soaking the fiber for 1h, separating the soaked fiber from the mixed solution, drying the fiber by spinning, and placing the fiber in saturated CaCl₂Soaking in the solution for 1 hour, taking out the fiber, washing with 80% (v/v) methanol aqueous solution for 1 time, washing with methanol aqueous solution containing 1.5% (w/v) PHMB for 1 time, washing with 80% (v/v) methanol aqueous solution for 1 time, washing for 2h each washing cycle, dehydrating, and drying at 40 deg.C to obtain antibacterial liquid-absorbing fiber with viscosity average molecular weight of 50 ten thousand and acryloyl group total substance amount substitution degree of 0.49.

Dissolving the antibacterial imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-peak area of protons in (a), calculated to give a substituted acryloyl group with a content of R being-OCa of 39%; the balance being-OCH₂ CH₂ CH₂The OH content was 61%.

Shearing 0.2g antibacterial liquid absorption fiber, leaching for 24 hr, performing liquid chromatography test on the filtered leaching solution, and calculating to obtain PHMB content 3100PPM according to the result.

Example 10

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.25, dispersing the chitin fiber in 50mL of isopropanol, adding 5.08g of acrylic acid-2-hydroxyethyl ester, oscillating the mixture uniformly at room temperature, reacting the mixture in a constant-temperature water bath at the temperature of 55 ℃ for 58 hours, and mixing the reacted chitin fiber with the reaction mixtureSeparating the mixed solution, washing with 80% (v/v) methanol aqueous solution for 2 times, taking out the fiber, drying, dispersing in 80% (v/v) methanol aqueous solution, dripping 30% (w/v) potassium hydroxide aqueous solution, adjusting pH of the mixed solution of methanol and potassium hydroxide aqueous solution to 11.5, soaking for 1 hr, separating the soaked fiber from the mixed solution, drying, placing in saturated CaCl₂Soaking in the solution for 1 hour, washing with 80% (v/v) methanol aqueous solution for 1 time, washing with methanol aqueous solution containing 1.5% (w/v) PHMB for 1 time, washing with 80% (v/v) methanol aqueous solution for 1 time, washing for 3h each washing cycle, dehydrating, and drying at 40 deg.C to obtain antibacterial liquid-absorbing fiber with viscosity average molecular weight of 50 ten thousand and acryloyl group substitution degree of 0.55.

Dissolving the antibacterial imbibing fiber in 1% CD₃D of COOD₂In O, nuclear magnetic hydrogen spectrometry is used to respectively measure-NCH₂-、-OCH₂-peak area of protons in (a), calculated to give a substituted acryloyl group with a content of R being-OCa of 27%; the balance being-OCH₂ CH₂ CH₂The OH content was 73%.

Shearing 0.2g of antibacterial liquid-absorbing fiber, leaching for 24h, performing liquid chromatography test on the filtered leaching solution, and calculating to obtain the PHMB content of 3300PPM according to the result.

Example 11

Weighing 5g of chitin fiber with the length of 6cm and the p/(m + n + p) of 0.25, dispersing the chitin fiber in 50mL of isopropanol, adding 6.30g of acrylic acid, uniformly oscillating at room temperature, reacting in a constant-temperature water bath at 70 ℃ for 40h, separating the reacted chitin fiber from a reaction mixed solution, washing for 2 times by using an 80% (v/v) methanol aqueous solution, taking out the fiber, spin-drying, washing for 1 time by using an 80% (v/v) methanol aqueous solution, washing for 1 time by using a methanol aqueous solution containing 2% (w/v) PHMB, washing for 1 time by using an 80% (v/v) methanol aqueous solution, washing for 2h in each washing cycle, dehydrating, and drying at 40 ℃ to obtain the antibacterial liquid absorbing fiber with the viscosity-average molecular weight of 8 ten thousand and the quantity substitution degree of the total acryloyl substances of 0.75.

Dissolving the antibacterial imbibing fiber in 1% CD₃D of COOD₂And O, performing nuclear magnetic hydrogen spectrum test. The results show thatAs for chitin fiber raw material, the antibacterial imbibing fiber only has two new absorption peaks at chemical shifts of 2.3 and 3.1, and is attributed to-NCH₂CH₂CO-, indicating that R is-OH, the content is 100%, and the substitution degree of the amount of the acryl group-containing total substance by calculation is 0.75.

Shearing 0.2g of antibacterial liquid absorption fiber, leaching for 24h, performing liquid chromatography test on the filtered leaching solution, and calculating to obtain the PHMB content of 5000PPM according to the result.

TABLE 3 basic parameters of the antimicrobial imbibing fibers

In the above table, the calculation process of each embodiment is as follows:

and testing the substitution degree of acryloyl groups at different sites of the cross section of the fiber by using EDS (electronic Destruction System), namely completely hydrolyzing the antibacterial liquid absorption fiber into potassium carboxylate by using a KOH (potassium hydroxide) solution, completely cleaning and drying, wherein the amount of K is equal to that of carboxylate radical substances, and the content of K is obtained by EDS testing, so that the amount of the carboxylate radical substances can be calculated, and the substitution degree of the acryloyl groups is calculated.

TABLE 4. absorbency Performance of the antimicrobial liquid absorbent fibers

Comparative example

A series of fibers having the same degree of substitution (Do/Dx ═ 1) from the center point of the cross section of the fiber to the edge of the fiber were prepared, and the morphology after liquid absorption was examined by the following method, and the state of retention of the morphology of the fibers after the fibers were contacted with the liquid was observed.

Weighing 8.3g NaCl and 0.277g CaCl₂Adding distilled water to dissolve, placing in volumetric flask, and adding distilled waterThe volume is fixed to 1000mL, and the obtained solution is solution A specified in British pharmacopoeia. The solution simulates the content of main metal ions in human blood.

Morphological contrast of imbibed fibers

Taking 1 fiber, fixing two ends of the fiber on a glass sheet by using a double-sided adhesive tape, dripping 0.25mL of solution A into the middle part of the fiber, standing the fiber for 30min at 37 ℃, taking out the fiber, and observing the shape change of the fiber after imbibing the liquid under an optical microscope.

Comparative example	p/(m+n+p)	Mη	m/(m+n+p)(Ds)	Do/Dx	Liquid absorption amount (times)
						1	0.25	8 ten thousand	0.70	1	Can not measure
2	0.25	300 ten thousand	0.18	1	3.5

As a result, it was difficult to measure the exact liquid absorption amount since the fiber of comparative example 1 had a poor intact form, and it was presumed that the liquid absorption amount was lower than that of the present invention in comparative example 2, although it could be measured, the microstructure of the uniformly substituted fiber was maintained after liquid absorption at the same substitution degree, but the microstructure was not strong enough to bind water since it was slightly dissolved compared with the present invention, and the water was partially lost after spinning and drying.

Example 12

The antibacterial liquid-absorbing fiber (namely, the liquid-absorbing fiber is provided with the polyhexamethylene biguanide) and the cotton fiber in the Kerlix dressing (the cotton fiber is provided with the polyhexamethylene biguanide) are respectively placed in a non-contact submicron spatial Raman synchronous measurement system (mIRage, United states photothermal spectroscopy company) for imaging analysis, and the mIRage reflection mode is used, wherein the IR energy is 4%, and the probe laser energy is 5%.

The infrared analysis results of the liquid-absorbing bactericidal fiber of the invention are shown in figures 2A-2B and figures 3A-3B, and the infrared analysis results of Kerlix dressing are shown in figures 4A-4C.

Referring to fig. 2A-2B and fig. 3A-3B, infrared imaging analysis is performed from the cross-section and side of the liquid-absorbent bactericidal fiber of the present invention, with the flat-tailed arrow representing PHMB and the dovetail arrow representing the liquid-absorbent fiber, indicating that PHMB is distributed substantially at the side of the liquid-absorbent fiber with less distribution of cross-section. Since the minimum precision of the infrared imaging image is 1 μm, PHMB is mainly distributed in the side surface of the liquid-absorbing sterilizing fiber, and the PHMB is proved to be distributed in the range of 0-1 μm in the surface depth of the liquid-absorbing sterilizing fiber.

Single wavelength infrared imaging and two wavelengths (1064 cm) from Kerlix cotton fiber cross section^-1And 1580cm^-1) The overlay process analysis shows that the image distribution of the cotton fiber is represented by the middle part (part different from the edge color) in fig. 4A, the image distribution of the PHMB is represented by the middle part (part different from the edge color) in fig. 4B, and the distribution of the PHMB on the cross section of the cotton fiber is shown asThe signals of the two signals in the superposition map are basically completely overlapped, and the signals represent the same spatial distribution.

Therefore, when the liquid-absorbing sterilizing fiber is applied to an antibacterial dressing, the antibacterial agent polyhexamethylene biguanide is mainly distributed on the surface layer of the side face of the fiber, so that the antibacterial agent is more easily and completely released, namely the utilization rate of the antibacterial agent is higher, and less antibacterial agent is needed when the same sterilizing effect is achieved.

Example 13

Weighing Kerlix dressing and 3cm by 3cm of the antibacterial dressing in the invention, then placing the Kerlix dressing and the antibacterial dressing in the invention into a sample bottle, respectively adding 10ml of 0.9% sodium chloride aqueous solution and 20ml of 0.9% sodium chloride aqueous solution into the sample bottle of the Kerlix dressing and the antibacterial dressing in the invention, placing the Kerlix dressing and the antibacterial dressing in a constant-temperature water tank at 37 ℃ after the samples are completely wetted, separating the samples from the solution after 30min, 1h, 3h, 6h, 24h, 3 by 24h, 5 by 24h and 7 by 24h, filtering the release solution by using a 0.45 mu m organic filter membrane, and taking 1.5ml of the filtered release solution for liquid phase test. The amount of PHMB released was measured by liquid chromatography using a 0.9% aqueous sodium chloride solution as a blank table control.

Referring to figure 5, the Kerlix dressing released approximately 600 μ g/g of polyhexamethylene biguanide over 15min, 700 μ g/g over 30min and 800 μ g/g over 7 days, i.e. the Kerlix dressing released approximately 7/8% of the polyhexamethylene biguanide over 3h and only 1/8 of the total release between 3h and 7 days.

In the antibacterial dressing, the amount of released polyhexamethylene biguanide in 15min is about 400 mug/g, the release amount in 1h is about 600 mug/g, the release amount in 3h is about 750 mug/g, the release amount in 7h is about 900 mug/g, the release amount in 24h is about 1300 mug/g, the release amount in 3 days is about 1400 mug/g, and the release amount in 7 days is about 1500 mug/g, so that the antibacterial dressing can better realize the slow release of the polyhexamethylene biguanide, thereby prolonging the antibacterial failure, and the release amount in 7 days is increased day by day, which is beneficial to wound healing.

Example 14

Respectively preparing the liquid absorption fibers in the embodiments 1 to 6 into single-layer non-woven fabrics by the processes of opening, carding, single-layer lapping, needling and the like; the antibacterial liquid-absorbent fibers of examples 7 to 11 were subjected to opening, carding, single-layer lapping, needling, and the like to prepare single-layer nonwoven fabrics.

And placing the non-woven fabric made of the one layer of the liquid absorption fiber between the non-woven fabrics made of the upper layer and the lower layer of the antibacterial liquid absorption fiber, and preparing the composite non-woven fabric dressing by a needling composite process.

[ rat infection wound repair test ]

Test method

100 SD rats were randomly divided into a control group and an experimental group (antimicrobial dressing example 14-1 to example 14-4), and 20 rats were collected. The method comprises the steps of carrying out intraperitoneal injection anesthesia by using 2% pentobarbital sodium solution (30mg/kg), depilating the back by using 8% sodium sulfide, disinfecting by using 70% ethanol cotton balls with volume fraction, and scalding two circular II-degree wound surfaces with the diameter of 2.5cm up and down along the spinal column by using an adjustable electric iron instrument with a YLS-5Q model at the temperature of 80 ℃ for 8s, wherein the interval between the wound surfaces is 2 cm. The diameter of the iron head is 2.5cm, and the pressure is 1 kg. Dripping 25 μ L of 10-concentration solution onto each wound surface⁶A suspension of CFU/mL Pseudomonas aeruginosa (ATCC 27312) was immediately applied to the wound surface and a polyurethane film dressing (Tegaderm transparent dressing, 3M company, USA) was applied to the wound surface, and the infected wound surface was formed after 24 hours.

After the infected wound surface is formed, removing the polyurethane film dressing on the wound surface, covering the wound surface of the experimental group with the dressing of the antibacterial dressing example 14-1-example 14-4, covering the control group with gauze, wrapping and fixing with an external bandage, and feeding in a single cage. 5 rats are sacrificed at 3, 7, 14 and 21d of the repair, the healing condition of the wound surface of the animal is observed, and the wound surface tissue is taken for bacterial culture counting and pathological histological analysis.

Test results

The areas of unhealed wounds 7, 14 and 21 days after the repair of the experimental group are lower than those of the control group (P < 0.05). After 3 days of repair, necrosis of squamous epithelial layer of wound surface skin epidermis, structural damage of hair follicle and skin accessory in dermis layer can be seen in two groups, and meanwhile, infiltration of unequal number of neutrophils and lymphocytes in injured skin tissues can be seen. After 21 days of repair, the epithelium of the control group is well repaired, a little lymphocyte infiltrates, and crusts can be seen; the epithelium of the experimental group is well repaired, and the complete new squamous epithelium layer can be seen without inflammatory cell infiltration. The experimental group has better repairing effect on the scald wound surface than the gauze group.

The results of bacterial culture of wound tissue showed that at each time point, the number of bacteria in the experimental group was significantly lower than that in the control group (as shown in table 5), and compared to the number of bacteria at the time of initial infection of the wound (10)⁶CFU/mL), the number of experimental groups decreased by at least 3 orders of magnitude (examples 14-1, 10)³CFU/g) shows that the experimental group has obvious effect on reducing and controlling wound infection.

TABLE 5 bacterial count in wound tissue (CFU/g)

	3 days	7 days	14 days	21 days
					Antimicrobial dressing example 14-1	7×10⁵	5×10⁴	1×10⁴	1×10³
Antimicrobial dressing example 14-2	3×10⁵	1×10⁴	3×10³	8×10²
					Antimicrobial dressing examples 14-3	1×10⁵	7×10³	9×10²	5×10²
Antimicrobial dressing examples 14-4	8×10⁴	2×10³	3×10²	1×10²
					Control group	2×10⁸	1×10⁸	5×10⁷	1×10⁷

The foregoing is a more detailed description of the present invention that is presented in conjunction with specific embodiments, and the practice of the invention is not to be considered limited to those descriptions. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims

1. An antibacterial dressing is characterized by comprising at least one layer of antibacterial liquid-absorbing fiber non-woven fabric and at least one layer of liquid-absorbing fiber non-woven fabric, wherein one side of the antibacterial liquid-absorbing fiber non-woven fabric is used for being applied to a wound, and the antibacterial liquid-absorbing fiber non-woven fabric is used for being applied to the wound, and the antibacterial liquid-absorbing fiber non-woven fabric is used for absorbing

wherein the content of the first and second substances,

r is at least 1 selected from the group consisting of-OH, -ONa, -OK, -OCa;

m + n + p ═ 1 formula 1,

p/(m + n + p) ═ 0.05-0.30 formula 2;

ds is 0.09-0.8, formula 3,

Do/Dx is 0 to 0.7, formula 4,

2. The antimicrobial dressing of claim 1, comprising at least three layers of nonwoven fabric, wherein the antimicrobial liquid-absorbent fiber nonwoven fabric is provided on both sides of the outer side of the antimicrobial dressing, and at least one layer of nonwoven fabric of the intermediate layer of the antimicrobial dressing is made of the liquid-absorbent fiber.

3. The antimicrobial dressing of claim 1 or 2, wherein said antimicrobial dressing has a grammage of between 60 and 250 gsm.

4. The antimicrobial dressing of claim 1 or 2, wherein the polyhexamethylene biguanide is present in the liquid-absorbent fiber in an amount of 1000-5000ppm by weight.

5. The antimicrobial dressing of claim 1 or 2, wherein the polyhexamethylene biguanide is present in the liquid-absorbent fiber in an amount of 3000-5000ppm by weight.

6. Antimicrobial dressing according to claim 1 or 2, characterized in that the polymer has a viscosity average molecular weight η in the range of 5 to 1000 ten thousand.

7. The antimicrobial dressing of claim 1 or 2, wherein said liquid-absorbent fibers have an overall degree of substitution Ds of 0.4 to 0.5.

8. The antimicrobial dressing of claim 1 or 2, wherein Do/Dx is 0 to 0.4.

9. The antimicrobial dressing of claim 1 or claim 2, wherein the antimicrobial dressing reduces the number of bacteria at the wound site by at least 1000-fold within 21 days of application to the wound.

10. The application of an antibacterial dressing in the field of biomedicine is characterized in that the antibacterial dressing is the antibacterial dressing as claimed in any one of claims 1 to 9.