CN111254438A

CN111254438A - Method for improving lyophobic performance of surface of surgical instrument

Info

Publication number: CN111254438A
Application number: CN202010133983.1A
Authority: CN
Inventors: 底月兰; 王海斗; 刘明; 刘韬; 郑博源; 王力
Original assignee: Academy of Armored Forces of PLA
Current assignee: Academy of Armored Forces of PLA
Priority date: 2020-03-02
Filing date: 2020-03-02
Publication date: 2020-06-09
Also published as: WO2021175000A1

Abstract

The invention discloses a method for improving the liquid repellency of the surface of a surgical instrument, which comprises the following steps: micro-nano dual structures with micro-holes and nano-particles densely distributed are generated on the surface of the surgical instrument; immersing the surgical instrument with the micro-nano double structure into PFDTES methanol solution for modification; and (4) carrying out high-temperature curing on the modified surgical instrument. The invention can improve the lyophobic performance on the surface of the surgical instrument and prolong the service life.

Description

Method for improving lyophobic performance of surface of surgical instrument

Technical Field

The invention relates to the technical field of stainless steel surface treatment, in particular to a method for improving the surface lyophobic performance of a surgical instrument.

Background

Surgical instruments are often contacted with physiological environments such as blood, tissue fluid and the like, so that the instruments are easy to rust, and great negative effects are generated on the recycling of the surgical instruments. Most surgical instruments contain tooth sockets and joints, rusted and solidified organic matters are easy to accumulate on the inner surface of a semi-closed instrument (such as a suction apparatus) with a complex shape, are difficult to clean, form a bacterial biofilm, and seriously affect a human body in clinical operations, even harm life. Meanwhile, the improvement of the self-cleaning performance of the surface of the instrument has important significance for improving the cleaning efficiency and the cleaning qualification rate of the surgical instrument.

Stainless steel is a common metal material, and has been widely used due to its excellent mechanical properties, low temperature resistance, corrosion resistance, wear resistance, and processing properties. However, the treatment technology for stainless steel with special shape and size has certain selectivity and limitation, in the prior art, chemical etching is usually used for constructing a hydrophobic structure on the surface of the stainless steel, namely, etching liquid capable of corroding the surface of a matrix is prepared, and then the matrix is soaked in the etching liquid for reaction for a certain period of time. However, stainless steel has certain corrosion resistance, and the physical and chemical properties of stainless steel are different due to different types of stainless steel components and different contents of the stainless steel components, so that the method for constructing the hydrophobic structure on the surface of different stainless steel cannot be completely used with etching liquid. A common surgical instrument material is martensitic stainless steel, such as 3Cr13 stainless steel. Therefore, how to make the surface of the surgical instrument have a certain lyophobic performance and improve the reusability of the instrument is an important issue to be solved in the industry at present.

Disclosure of Invention

The embodiment of the invention provides a method for improving the surface lyophobic performance of a surgical instrument, so as to improve the surface lyophobic performance of the surgical instrument and prolong the service life.

Therefore, the invention provides the following technical scheme:

a method of enhancing the liquid repellency properties of a surgical instrument surface, said method comprising the steps of:

micro-nano dual structures with micro-holes and nano-particles densely distributed are generated on the surface of the surgical instrument;

immersing the surgical instrument with the micro-nano double structure into PFDTES methanol solution for modification;

and (4) carrying out high-temperature curing on the modified surgical instrument.

Optionally, the micro-nano dual structure for generating micro-pores and nano-particles densely distributed on the surface of the surgical instrument comprises:

performing sand blasting treatment on the surface of the surgical instrument, and cleaning the surface of the surgical instrument by using absolute ethyl alcohol after the sand blasting is finished;

and immersing the cleaned surgical instrument into a pre-prepared etching solution for dislocation etching to form a micro-nano dual structure with a micro-hole structure and densely distributed nano particles on the surface of the surgical instrument, and cleaning the surgical instrument after etching.

Optionally, the blasting parameters include: the granularity is 140-160 meshes, the pressure is 0.7-0.9 MPa, the distance between a sand blasting muzzle and a surgical instrument is 4.5-5.5 cm, and the sand blasting time is 170-190 s.

Optionally, the etching solution is prepared from hydrochloric acid, hydrofluoric acid, and distilled water.

Optionally, the etching solution includes: 40ml of 37% hydrochloric acid, 2.5ml of 40% hydrofluoric acid and 12.5ml of distilled water.

Optionally, the etching time is 30 minutes.

Optionally, the cleaning the surgical instrument after the etching is completed includes:

the surgical instruments are cleaned by distilled water and then cleaned by absolute ethyl alcohol.

Optionally, the method further comprises:

before the surface of the surgical instrument is subjected to sand blasting, the surface of the surgical instrument is polished by sand paper, and the polished surgical instrument is immersed in absolute ethyl alcohol for cleaning and blow-drying.

Optionally, the sanding of the surgical instrument surface with sandpaper comprises:

and sequentially polishing the surfaces of the surgical instruments from coarse to fine by using abrasive paper of various types.

Optionally, the modification duration is 10 hours or more.

According to the method for improving the liquid repellency of the surface of the surgical instrument, provided by the embodiment of the invention, aiming at the characteristic of stainless steel used as a surgical instrument material, the surface of the surgical instrument is subjected to micro deformation and stress concentration by a physical method of sand blasting, and after the surgical instrument is immersed in dislocation etching liquid, a stress concentration area is preferentially etched, so that an obvious micron hole structure is formed on the surface of the surgical instrument; meanwhile, due to the action of the dislocation etching liquid, nano-scale gullies and particle structures are formed on the surface of the surgical instrument, so that a micro-nano double structure is formed on the surface of the sample. According to the scheme of the invention, a micro-nano dual structure with hydrophobic property is constructed on the surface of the surgical instrument by using a method combining sand blasting and chemical etching, and then the surface energy of the matrix is reduced and the lyophobic property of the matrix is fully improved through low surface energy modification.

Drawings

In order to more clearly illustrate the embodiments of the present application or technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to the drawings.

FIG. 1 is a flow chart of a method for improving the liquid repellency of a stainless steel surface according to an embodiment of the present invention;

FIG. 2 is a three-dimensional topography of a surgical instrument after different time grit-blasting in accordance with an embodiment of the present invention;

FIG. 3 is a schematic representation of the change in wetting contact angle of a surgical instrument after different blasting times;

FIG. 4 is a schematic representation of the change in wetting contact angle of a surgical instrument after different etch times;

FIG. 5 is a surface topography of a surgical instrument after various etch times;

FIG. 6 is a micro-nano dual structure of the surface of a surgical instrument;

FIG. 7 is a schematic view of the micro-nano dual structure on the surface of the surgical instrument after the two-step sand blasting and etching process;

FIG. 8 is a graph of surgical instrument surface roughness versus contact angle;

FIG. 9 is a graph of surgical instrument surface skewness versus contact angle;

FIG. 10 is a schematic view of the lyophobic effect of the surgical instrument after modification for various periods of time;

FIG. 11 is a graph showing the result of a blood-thinning effect test on the surface of a surgical instrument sample using serum.

Detailed Description

In order to make the technical field of the invention better understand the scheme of the embodiment of the invention, the embodiment of the invention is further described in detail with reference to the drawings and the implementation mode.

Surgical medical instruments (such as scissors, forceps, tweezers and the like) are mostly made of martensitic stainless steel. The martensitic stainless steel matrix structure is martensite, wherein the mass fraction of chromium is 12-18%, the hardenability is good, and the physical and mechanical properties can be improved through a proper heat treatment process, so that the martensitic stainless steel matrix structure has higher hardness and strength. In the case of martensitic stainless steel, the high carbon content can increase the strength and hardness and enhance the wear resistance, but simultaneously reduce the corrosion resistance, and particularly in physiological environments such as blood, tissue fluid and the like, the corrosion of chloride ions to instruments is not a little great deal. However, if the carbon content is reduced, the steel material can not meet the strength and hardness required by the operation, the wear resistance is poor, and the service life is short. Therefore, the martensitic stainless steel needs to be further surface-treated on the basis of manufacturing so as to improve the strength, the hardness and the corrosion resistance of the martensitic stainless steel.

Aiming at the situation, the embodiment of the invention provides a method for improving the surface hydrophobic property of stainless steel, aiming at the characteristics of the stainless steel used as a surgical instrument material, the physical method of sand blasting is adopted to enable the surface of the surgical instrument to generate micro deformation and stress concentration, after the surgical instrument is immersed in dislocation etching liquid, the stress concentration area is preferentially etched, and the surface of the surgical instrument forms an obvious micron hole structure; meanwhile, due to the action of the dislocation etching liquid, nano-scale gullies and particle structures are formed on the surface of the surgical instrument, so that a micro-nano double structure is formed on the surface of the sample. And the surface energy of the matrix is reduced through low surface energy modification, and the lyophobic performance of the matrix is fully improved.

As shown in fig. 1, the method for improving the liquid repellency of the surface of the stainless steel mainly comprises the following steps:

step 101, generating a micro-nano dual structure with micro-holes and nano-particles densely distributed on the surface of a surgical instrument;

step 102, immersing the surgical instrument with the micro-nano dual structure into PFDTES methanol solution for modification;

and 103, performing high-temperature curing on the modified surgical instrument.

Further, before the surface of the surgical instrument is subjected to the sand blasting treatment, the surface of the surgical instrument can be pretreated to remove processing marks and impurities (such as oil stains and the like) on the surface of the surgical instrument. The pretreatment mainly comprises the following processes:

firstly, grinding the surface of a surgical instrument by using sand paper; the polished surgical instrument is then rinsed in absolute ethanol and blown dry, such as by ultrasonic vibration for 5 minutes.

It should be noted that, when the surface of the surgical instrument is polished by using the sand paper, different types of sand paper can be selected to complete the polishing process according to the actual application requirements. Of course, various types of sand paper can be used to grind the surface of the surgical instrument from coarse to fine, for example, 600#, 800#, 1000#, 1500#, 2000# sand paper can be used to grind the surface of the surgical instrument.

In the embodiment of the invention, aiming at the characteristics of martensitic stainless steel used for surgical instruments, such as 3Cr13 stainless steel, a micro-nano dual structure with micro-pores and nano-particles densely distributed is generated on the surfaces of the surgical instruments by adopting a treatment mode of combining sand blasting and dislocation etching. Specifically, firstly, performing sand blasting treatment on the surface of a surgical instrument, and cleaning the surface of the surgical instrument by using absolute ethyl alcohol after the sand blasting is finished; then, the cleaned surgical instrument is immersed into the pre-prepared etching solution for dislocation etching, so that a micro-hole structure and a micro-nano dual structure with densely distributed nano particles are formed on the surface of the surgical instrument, and the surgical instrument is cleaned after the etching is finished. Wherein:

the blasting parameters may be as follows: the granularity is 140-160 meshes, the pressure is 0.7-0.9 MPa, the distance between a sand blasting muzzle and a surgical instrument is about 4.5-5.5 cm, and the sand blasting time is 170-190 s. The sand blasting time can be set according to the requirement on the surface flatness of the sample, and the longer the sand blasting time is, the lower the flatness of the surface of the sample is, and the more complex the microstructure is.

Adopting sand blasting parameters: the distance between the mouth of the sand blasting gun and the surgical instrument is about 5cm, sand blasting parameters with the granularity of 150 meshes and the pressure of 0.8MPa are used for respectively carrying out sand blasting treatment on the surgical instrument for 60s, 120s and 180s, and the three-dimensional appearance of the surface of the treated sample is shown in figure 2. Wherein (a) the corresponding blasting time: 60 s; (b) corresponding blasting time: 120 s; (c) corresponding blasting time: 180 s.

As can be seen from fig. 2, the lower the flatness of the sample surface, the more complex the microstructure as the blasting time is extended.

The relationship between the sandblasting time and the Wetting Contact Angle (WCA) is shown in FIG. 3, where the wetting contact angle is the tangent of the gas-liquid interface at the intersection of the gas, liquid and solid phases, and the angle θ between the tangent and the solid-liquid boundary on the liquid side, and the magnitude of the contact angle reflects the degree of wetting of the liquid on the solid.

As can be seen from fig. 3, the sand blasting time is positively correlated to the wetting contact angle, and a large amount of gully structures formed by the sand blasting are more favorable for storing air therein, so as to increase the gas-liquid contact area, and the longer sand blasting time makes the distribution of the gully structures denser, thereby increasing the wetting contact angle.

The etching liquid is prepared from hydrochloric acid, hydrofluoric acid and distilled water, and the proportion of the components can be as follows: 40ml of 37% hydrochloric acid, 2.5ml of 40% hydrofluoric acid, 12.5ml, and the etching time can be set as required. Further, after the etching is completed, the surgical instrument may be cleaned, such as: the surgical instruments are cleaned by distilled water and then cleaned by absolute ethyl alcohol.

Assuming that 40ml of etching solution prepared from 37% hydrochloric acid, 2.5ml of 40% hydrofluoric acid and 12.5ml of distilled water is selected, the Cr3C surgical instrument subjected to the sand blasting treatment is respectively etched for 20min, 30min, 40min, 60min and 90min, then is cleaned by a large amount of distilled water, and then the sample is cleaned in absolute ethyl alcohol by ultrasonic oscillation for 10 min, wherein the change of the wetting contact angle is shown in FIG. 4.

As can be seen from FIG. 4, the wetting contact angle increases with the increase of the etching time between 20min and 30min, reaches a maximum value of 109.67 degrees when the etching time is 30min, the contact angle rapidly decreases at 30min to 40min with the increase of the etching time, and the value of the contact angle slowly decreases and becomes stable after 40 min.

The surface topography of the surgical instrument after different etching times was changed as shown in fig. 5, wherein (a): not etching the sample; (b) the method comprises the following steps Etching for 20 min; (c) etching for 30 min; (d) etching for 60 min; (e) and etching for 90 min.

As can be seen from fig. 5, as the etching time is prolonged, the complexity of the surface structure of the surgical instrument increases, and a significant hole structure appears. The reason for generating the appearance is that the gravel is deformed due to the impact of the gravel on the surface of the substrate, a plurality of micro-holes are generated on the surface of the substrate after sand blasting, the volume of the micro-holes is obviously increased under the action of chemical etching, the size of the micro-holes is increased in the horizontal direction and the depth direction, and the macro-structure shows more obvious hole structure. However, there is a difference in the spreading speed in the horizontal and depth directions, and the sample surface cannot be formed with large and deep holes by simply prolonging the etching time, as shown in fig. 5(e), when the etching time reaches 90 minutes, some large and shallow pits appear in the hole structure, and the hole structure is blurred compared with fig. 5 (c).

After etching, polyhedral nanoparticles appear on the surface of the surgical instrument, are densely distributed on the surface of the sample, are uniformly distributed, and are analyzed to be carbides of Fe and Cr by EDS. The appearance is formed because Fe in a sample is dissolved into an etching solution due to etching, the lack of Fe on the surface of the sample enables the Fe to be dispersed and distributed in 3Cr13, and nano Cr3C particles with strong corrosion resistance are exposed on the surface. After two steps of sand blasting and etching, a micro-nano dual structure with a micro-hole structure and a nano-particle densely distributed is formed on the surface of the sample, as shown in fig. 6, wherein the white light reflecting position in the left picture is the nano-particle structure densely distributed position, and the right picture is a local amplification effect picture of the left picture.

The sand blasting treatment forms some hole structures and deformation defect parts on the surface of the surgical instrument, the chemical etching makes the hole structures enlarged and deepened, and the nano-scale particle structures are constructed by combining the self characteristics of the materials. The micro-nano dual structure is obtained on the surface of the surgical instrument through the treatment of the two-step process of sand blasting and etching, and the process principle is shown in figure 7. Many studies have shown that micro-nano dual structures can significantly increase the contact angle of a surface. The pore structure of the rough surface can store air therein to form a gas layer, thereby avoiding direct contact between liquid and the solid substrate. It is known from the Cassie-Baxter model that the increase of the gas fraction in the contact area can increase the apparent contact angle (i.e. the actually measured contact angle), and the complex hole structure with the fluctuation can well store air in the hole, thereby increasing the gas fraction and increasing the contact angle.

The inventors have made statistics on the surface topography parameters of the different sandblasting and etching processes as shown in table 1.

TABLE 1 Process parameters and contact angles

After sand blasting and etching processes, the relation between the surface topography parameter of the sample and the wetting contact angle is shown in fig. 8 and 9, wherein the square points represent hydrophilic points, and the circular points represent hydrophobic points.

In step 102, the etched surgical instrument may be immersed in a 5mmol/L methanol solution of PFDTES (1H, 2H-perfluorodecyltriethoxysilane) at room temperature, and modified for a certain period of time, for example, the modification period is greater than or equal to 10 hours.

In the step 103, the high temperature curing may be performed at an environment of 120 to 150 ℃ for about 1 to 2 hours.

The lyophobic effect of the modification at different time is shown in fig. 10, the wetting contact angle of the matrix is not changed greatly after 3 hours of modification, but the maximum contact angle of the matrix is 142.49 degrees at 12 hours of modification. Meanwhile, the wetting contact angle of the modified substrate surface is greatly improved. The reaction mechanism is as follows: PFDTES molecules are linked with hydroxyl on the surface of the matrix through chemical bonds, and are densely arranged on the surface of the matrix through a condensation polymerization reaction, and-CF 3 groups with extremely low surface energy are distributed on the outer side, so that the surface energy of the matrix is reduced, and the wetting contact angle is improved.

According to the method for improving the lyophobic performance of the stainless steel surface, provided by the embodiment of the invention, aiming at the characteristics of stainless steel used as a surgical instrument material, the physical method of sand blasting is adopted to enable the surface of the surgical instrument to generate micro deformation and stress concentration, and after the surgical instrument is immersed in dislocation etching liquid, the stress concentration area is preferentially etched, so that an obvious micron hole structure is formed on the surface of the surgical instrument; meanwhile, due to the action of the dislocation etching liquid, nano-scale gullies and particle structures are formed on the surface of the surgical instrument, so that a micro-nano double structure is formed on the surface of the sample. And the surface energy of the matrix is reduced through low surface energy modification, and the lyophobic performance of the matrix is fully improved.

Under the condition of room temperature, the viscosity of water is 0.8937, while the viscosity of serum is 1.5-1.8, and the two physical properties are different, so the inventor further uses the serum to test the blood thinning effect of the surface of the surgical instrument which is chemically etched and modified by low surface energy by using the scheme of the invention.

The main process parameters for surface treatment of surgical instruments are as follows: the sand blasting mesh number is 150 meshes, the pressure is 0.8MPa, the sand blasting time is 180s, and the etching time is 30 min.

The following tests were performed on the surface of the surgical instrument sample treated with the above process parameters: 5 mul of serum is dripped on the surface of a sample, after the liquid drop is stable, a contact angle measuring instrument is used for measuring a contact angle, the static contact angle reaches 132 degrees, and as shown in figure 11, a better blood dredging effect is achieved.

It should be noted that the surfaces of the surgical instruments (e.g., scissors, forceps, tweezers, etc.) mentioned in the embodiments of the present invention include not only the external surfaces thereof, but also the internal surfaces thereof, especially the surgical instruments including gullets and joints.

The surface of the surgical instrument made of the martensitic stainless steel material is treated by the method, so that the surgical instrument has better strength, hardness and corrosion resistance, can be used in physiological environments such as blood, tissue fluid and the like for a long time, not only can the service life be effectively prolonged, but also the use safety of the surgical medical surgical instrument is ensured.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The present invention has been described in detail with reference to the embodiments, and the description of the embodiments is provided to facilitate the understanding of the method and apparatus of the present invention, and is intended to be a part of the embodiments of the present invention rather than the whole embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative effort shall fall within the protection scope of the present invention, and the content of the present description shall not be construed as limiting the present invention. Therefore, any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method of enhancing the lyophobic properties of a surgical instrument surface, the method comprising the steps of:

2. The method of claim 1, wherein the generating of the micro-vugs and nanoparticle-dense micro-nano duplex structure on the surface of the surgical instrument comprises:

3. The method of claim 2, wherein the blasting parameters comprise: the granularity is 140-160 meshes, the pressure is 0.7-0.9 MPa, the distance between a sand blasting muzzle and a surgical instrument is 4.5-5.5 cm, and the sand blasting time is 170-190 s.

4. The method of claim 2, wherein the etching solution is prepared from hydrochloric acid, hydrofluoric acid, and distilled water.

5. The method according to claim 4, wherein the etching liquid comprises: 40ml of 37% hydrochloric acid, 2.5ml of 40% hydrofluoric acid and 12.5ml of distilled water.

6. The method of claim 2, wherein the etching time period is 30 minutes.

7. The method of claim 2, wherein cleaning the surgical instrument after the etching is complete comprises:

8. The method according to any one of claims 1 to 7, further comprising:

9. The method of claim 8, wherein sanding the surface of the surgical instrument comprises:

10. The method of claim 1, wherein the modification period is 10 hours or more.