JPH02290228A - Module composed of regenerated hollow cellulose fiber membrane for filtration in very small amount - Google Patents

Abstract

PURPOSE:To separate viruses, etc., from protein contg. substances by placing into a cylindrical body a few pieces of regenerated cuprammonium hollow cellulose fiber membranes having an average hole diameter within a specific range, exposing one end of the cylindrical body to atmospheric pressure and sealing said membranes completely in the cylindrical body. CONSTITUTION:A module 5 is formed by placing into a cylindrical body 3 one piece to a few pieces of regenerated cuprammonium hollow cellulose fiber membrane 1 having an average hole diameter within the range of 0.02-0.2mum. The cylindrical body 3 is exposed to atmospheric pressure at one end of the module 5 but with the membranes 1 completely sealed therein, while, at the other end of the module 5, one touch-fit fluid coupling (plug) 4 is firmly fitted over the membrane 1 and the cylindrical body 3 with a filling agent 2 interposed between the coupling and the membrane and with the membrane 1 left open to the outside. As a result, by inspecting the hollow fiber membrane for precise performance and the possible disadvantage, microorganisms and viruses can be separated and concentrated from a very small amt. of a valuable substance contg. protein.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a filtration module using a hollow fiber membrane used in precision filtration. For more details, see Medicine I, Microorganisms,
It can be used for virus isolation, removal, concentration tests, etc. in the biochemistry field, etc., and is particularly useful for separating trace amounts of valuable separation targets that contain biochemically useful proteins, such as microorganisms and virus culture fluids, virus-containing plasma, and unknowns. Isolates, removes, and removes microorganisms, viruses, and unknown pathogenic substances from liquids containing pathogenic substances.
Regenerated cellulose hollow fiber membrane suitable for concentrating trace amounts of 'il
This relates to overload modules.

(Prior Art) The separation device for separating hollow membranes used in the above-mentioned applications has recently been significantly developed with the progress of membrane separation technology. In other words, hollow fiber membranes have many excellent features such as a larger membrane area per unit volume than flat membranes, no need for reinforcing supports because they can be assembled as molded products, and ease of operation. ing. A known hollow membrane separator for industrial or medical use has a large number (for example, about iooooo membranes) of hollow membranes packed tightly in a plastic or metal outer cylinder, and both ends of the hollow fiber membranes are connected with an adhesive. The most common type was embedded in the

However, in the case of separation for purposes other than industrial or medical use, that is, for laboratory use, such as separation of microorganisms and viruses in the biochemical field, the volume to be separated is often small and valuable, less than 1 mQ. In the above-mentioned type of separator, it has been impossible to filter such a small amount of separation target because the separation target is lost due to the dendritic space inside and outside the hollow fiber membrane.

Therefore, when conducting such microfiltration experiments, conventionally a hollow fiber membrane is inserted and fixed at the tip of a syringe needle, the end of the hollow fiber is closed, and then the syringe needle is loaded into a syringe barrel containing the target to be separated. death,
A pressure filtration operation was performed.

However, problems such as breakage of the hollow fiber membrane due to the needle tip or excessive pressure often occur during operation; the performance and defects of the hollow fiber membrane cannot be inspected in advance; the target of separation/filtrate is susceptible to contact contamination; particularly, infection Various problems have arisen in that it is difficult to filter highly dangerous substances such as virus concentrates.

In addition, the materials for the hollow fiber membranes generally used in the above-mentioned separation experiments include cellulose acetate (CDA), polyacrylonitrile (PAN), and polymethyl methacrylate (PMMA).
, polypropylene (PP), polyethylene (PE),
There are polyvinyl alcohol (PVA), ethylene/vinyl alcohol copolymer (EVAL), etc., but these materials have the drawback of high protein adsorption. Due to this drawback, when an aqueous protein solution is filtered through these hollow fibers, a problem arises in that the filtration rate rapidly decreases.

(Problems to be Solved by the Invention) The purpose of the present invention is to perform accurate performance and defect inspection of hollow membrane membranes, and then separate and concentrate microorganisms, viruses, etc. from trace amounts of valuable separation targets including proteins. The purpose of the present invention is to provide a module for microfiltration that can be used for microfiltration.

(Means for Solving the Problems) The present invention provides a cuprammonium-method regenerated cellulose hollow fiber membrane (1) having an average pore size in the range of 0.02 μm to 0.2 μm, and one to several fibers in a cylinder (3). At the end of the module, the cylinder (3) is open to atmospheric pressure and the membrane (1) is completely sealed, while the other end of the module is At the end of the filler (
A one-touch quick fluid coupling (plug) (4) is fixed to the membrane (1) and the cylindrical body (3) via 2), and the membrane (1) is released to the outside system. This is a module for particle separation microfiltration.

In the present invention, it is necessary to use cuprammonium regenerated cellulose hollow fibers.

There are various methods for producing regenerated cellulose, such as the viscose method, the cellulose ester saponification method, and the copper ammonia method.
Due to differences in manufacturing conditions, they cannot be uniformly discussed as ``regenerated cellulose'' in terms of physical and chemical properties. In the copper ammonia method, the essential acid treatment produces fine pores and a unique molecular chain aggregate structure due to the removal of copper, so regenerated cellulose produced by the cuprammonia method has unique properties. The present inventors have discovered that a hollow fiber membrane made of cellulose regenerated by the cuprammonium method is one of the hollow fiber membranes with the lowest protein adsorption properties among existing hollow fiber membranes.

In the present invention, the viscosity average molecular weight of the cuprammonium regenerated cellulose is preferably 7X10' or more, and 0. IN
It is desirable that the amount of dissolved components in the Na011 aqueous solution is as small as possible. 40°C, 48 hours, 0.1N Nail
When immersed in an aqueous solution, this dissolved component is 10 ppm.
The hollow fiber is suitable as a filter medium for a separator of the present invention if the following conditions are met.

In order to produce hollow fibers made of cellulose as described above, regenerated cellulose is produced using a cuprammonium method using a high-purity cellulose raw material, or 0.0% is produced after producing the hollow system. I
It is sufficient to perform cleaning treatment with an aqueous NaOl solution for 72 hours or more.

It is more preferable to use a high purity cellulose raw material because the above-mentioned dissolved components are significantly reduced. Here, "high purity cellulose raw material" means that the α-cellulose content is 90-t%.
The above refers to cotton linters and wood valves with a degree of polymerization of 500 or more. For these raw materials, it is preferable to always use purified water in order to prevent decomposition and oxidation during bleaching and washing steps and to avoid contamination with impurities.

To produce regenerated cellulose using the cuprammonium method using the above-mentioned high-purity cellulose raw material, for example, it can be produced by the following method.

Cellulose link - (α-cellulose containing N 96% or more, average molecular ffi 2.6X 10S) prepared by a known method. A solution dissolved at a concentration of 8 wt% during the night was used as a spinning stock solution. This spinning stock solution is obtained by causing microphase separation using an acetone/ammonia/aqueous mixed solution as a coagulating agent and a hollowing agent, and then coagulating and regenerating it. Here, microphase separation means a state in which a concentrated layer or a diluted layer of polymer is dispersed and stabilized as particles having a diameter of 0.02 to several μm in a solution. The occurrence of microphase separation can be observed directly with the naked eye by the devitrification phenomenon of the yarn during spinning, or by scanning and transmission electron microscopy of the yarn after spinning.
It is confirmed by the presence of particles with a diameter of 1 μm or less and 0.02 μm or more.

In the present invention, it is necessary that the average pore diameter is in the range of 0.02 to 0.2 μm and one to several hollow fiber membranes are used as the filter medium.

In order to separate and concentrate microorganisms, viruses, etc. from valuable separation targets with large amounts of ia, it is necessary to minimize the filling capacity of the hollow system membrane (3"L). In other words, the amount of dead space inside and outside the hollow system must be minimized. In order to minimize the loss of target material, an ultra-small module using one to several hollow fiber membranes as a filter medium is required.It is possible to separate and concentrate particles with a particle size of 25 nm or more, such as microorganisms and viruses, and has sufficient In order to obtain a filtration rate, it is necessary that the average pore diameter is in the range of 0.02 to 0.2 μm, and the inner diameter and effective length of the hollow membrane are each 30 μm.
Desirably 0 μm and 20 cm or less. Average pore size is 0.02
When the thickness is less than μm, the strength of the hollow fiber membrane is significantly reduced.

Further, as a method for recovering the concentrated microorganisms and viruses trapped inside the hollow fiber membrane, the hollow fiber membrane after filtration can be decomposed by cellulose degrading enzyme cellulase and then recovered.

Since the module of the present invention uses one to several hollow membranes as filter media as described above, there is a high risk that the membranes will be damaged when handled as is. That is, by housing the membrane within the cylinder, it is protected from damage. Furthermore, filtration operations can be performed safely without touching highly dangerous separation targets such as contagious virus concentrates.

In the present invention, it is necessary that the hollow fiber membrane is housed in a cylinder, that the cylinder is opened to atmospheric pressure at the end of the cough cylinder, and that the membrane is completely closed. .

Furthermore, it is preferable to make the tube transparent or semi-transparent, as this makes it possible to observe the actual state of filtration. Furthermore, it is more preferable to include a scale on the cylindrical body, as this allows accurate grasping of the filtration rate.

Since the cylinder body is open to atmospheric pressure at one end of the cylinder body, filtration can be performed without increasing the internal pressure inside the cylinder body during filtration, improving the filtration efficiency and making it easier to collect the filter at night. Become.

Preferable materials for the cylinder include glass, transparent synthetic resin, transparent rubber, and the like. Also, considering the ease of handling and the risk of rupture, the relaxation modulus is 107~l0
A flexible material in the range of 9 dyne/cA is preferred.

In the present invention, a one-touch quick fluid coupling (plug) coupled to the membrane and the cylinder through a filler is fixed at the other end of the cylinder, and the membrane is opened to the outside system. It is necessary that the child is pregnant.

In detail, as shown in FIG. 1 as an example of the present invention, a cuprammonium regenerated cellulose hollow fiber membrane (1), a filler (2), a cylindrical body (3), and a one-touch quick fluid coupling (plug) are shown. (4). One end (8) of the hollow fiber membrane (1) is fixed with a filler and integrated with a one-touch quick fluid coupling (plug). Further, the hollow fiber membrane at the end (A) is opened to the outside system.

The other end (B) of the hollow fiber membrane is completely sealed, but in order to collect the filtrate, it is desirable that this end (B) not be joined to the cylinder.

By connecting the one-touch quick fluid coupling (plug) of this separator to the one-touch quick fluid coupling (socket) of the device shown in FIG. 2 as an example, a pressure of about 10 kg/cffl is applied to the hollow fiber membrane. It is possible to multiply by seven. That is, non-destructive performance tests (for example, gas permeation meteor measurements, hubble-boind measurements, etc.) and defect (pinhole) tests can be performed for every one to several hollow fiber membranes that are the filter media of the module.

Prior to describing embodiments of the module of the present invention, definitions of main technical terms (physical property values) used in this specification and methods for measuring them are shown below.

(Average pore diameter) A module for measuring the average pore diameter of regenerated cellulose hollow fibers using the cuprammonium method was prepared, and in the module state, the outflow of water from the hollow fiber membrane was measured, and the average pore diameter (D) was calculated from equation (1). I asked for

■: T: △P: A: Pr: μ: Porosity Pr is: Outflow rate (m1/min) Membrane thickness (μm) Pressure difference (mmHg) Membrane area (nf) Porosity Water viscosity (cp) ) It was determined in (2) 2 from the apparent density ρaw when swollen with water and the density ρρ of the polymer. In the case of cellulose, ρp=1.56 was used.

Pr(χ)-(1 1)aw/ρp) XIO
O (2) [Average molecular weight] By substituting the intrinsic viscosity [η] (mf/g) measured in a cupric ammonia solution (20"C) into equation (3), the average molecular weight (viscosity average molecular l) Mv Calculate.

Mv 1E η] X3.2 X I O 3(3) [
Virus inhibition coefficient] Logarithmic reduction rate of virus when virus-containing liquid is filtered with this module (J2ogreduction vol+
The blocking coefficient (hereinafter referred to as LRV) expressed in ie or LRV is calculated using equation (4).

LRV--log (Filtrate virus concentration/Original liquid virus concentration) (4) [Effects of the invention] By using the microfiltration module of the present invention,
It has become possible to separate, remove, and concentrate with high precision particles of 25nII1 or more, such as trace amounts of valuable microbial viruses, which were impossible to measure with conventional hollow fiber membrane modules.

(Example 1) Copper ammonia prepared from cellulose link (α-cellulose content 96% or more, average molecular weight m 2.6 x 10s) by a known method? It was dissolved in a solution at a concentration of 8 wt % and subjected to excessive defoaming to obtain a spinning stock solution. The spinning stock solution was passed through the outer spinning spout (outer diameter 2 mmφ) of the annular spinning spout.
m17 min, while as a hollow agent, 50 ml of acetone
% / 0.65 wt % ammonia / 49.35 wt % water was added to the central spinning spout (outer diameter 0.6 mmφ).
If/min, each sample was directly discharged into a mixed solution (coagulant) of 40 wt% acetone/0.65 imt% ammonia/59.35 wt% water (coagulant), and wound up at a speed of 10 m/min. In addition, the transparent blue fibrous material immediately after discharge gradually turned white, microphase separation occurred, and coagulation subsequently occurred, maintaining the shape of the fiber. Thereafter, it was regenerated with a 2 wt % sulfuric acid aqueous solution, and then washed with water. The inner diameter of the regenerated cellulose hollow fibers obtained by the ammonia method, which was obtained by solvent replacement and vacuum drying of the hollow fibers in a wet state, was 253.
5μm, film thickness 25.7μm, average pore diameter 32. On
It was II1. The hollow fiber was molded into a module (effective length: 8 cm) as shown in FIG.

When the above module was connected to the device shown in Figure 2, the module was filled with ethanol, and the pressure was gradually increased, the result was 9.
．． Bubbles were generated at 7 kg/c++T.

(bubble point: 9.7 kg/aft) was used in the a-passage experiment shown below.

Escherichia coli phage Phyex l74 (hereinafter referred to as φX174)
) (25r+m) is the filtration membrane area 1 c! The concentration of the original culture solution (peptone-yeast medium) was adjusted so that the number of cells per culture was 105. After assembling the apparatus shown in Fig. 3, put the culture solution 5 into the source solution tank and apply a pressure of 200 mm.
Constant pressure filtration was performed using Hg and 3 ml of filtrate was collected. φX174 was not detected in the collected filtrate.

If the amount of the source liquid is even smaller (lI!11 or less), it is also possible to directly pour the source liquid into the piping tube in front of the module and filter it without using the source liquid tank.

(Example 2) Using modules having different average pore diameters prepared in the same manner as in Example 1, a supernatant of a culture solution containing φX 174 was filtered using the method shown in FIG. The number of φX174 in the filtrate was measured, and the rejection rate (Ll?V) of φX174 by filtration was determined. The results are shown in Table 1.

Table 1 is a cross-sectional view of the average pore diameter of the module and the rejection ratio of φx174. However, the number of hollow membranes may be increased to several.

FIG. 2 is a schematic diagram of a non-destructive performance testing device for modules of the present invention. FIG. 3(a) shows an example of a filtration operation using the module of the present invention. If the amount of filtrate is small, the filtrate can be stored in the cylinder by arranging the module of the present invention in reverse.

1: regenerated cellulose hollow fiber membrane, 2: filler, 3: cylinder,
4: One-touch quick fluid coupling (plug), i2 module of the present invention, 6: Air or nitrogen cylinder, 7: Main valve, 8
: Pressure adjustment valve, 9: Pressure gauge, 10: Gas flow meter, 11:
One-touch quick fluid coupling (socket l-), 12: constant pressure pump, 137 source liquid tank, l4: liquid to be separated, 15:
Filtrate collection tube, step 6: Filtrate

[Brief explanation of drawings]

FIG. 1(a) is a sectional view of the hollow fiber longitudinal direction of the microfiltration module of the present invention. Figures 1 (b) and (c) are cross-sectional views along line A^ and line BB, respectively Patent applicant: Asahi Kasei Industries, Ltd. Procedural amendment (method) June 7, 1990 Director General of the Japan Patent Office Mr. Takeshi Yoshida I. Display of incident Patent Application No. 322131 of 1988 2. Name of invention Regenerated cellulose hollow fiber membrane microfiltration module 3. Relationship with the case of the person making the amendment Patent applicant 1-2-6 Dojimahama, Kita-ku, Osaka-shi, Osaka May 1, 1990
4th (shipment date 2.5.29) 5. 6. “Brief explanation of drawings” column of the original document and specification to be amended. Contents of amendment The applicant (seal) column of the application form will be amended as shown in the attached sheet. "Figure 3 (a)" on page 16, line 4 of the specification is corrected to "Figure 3."

Claims (1)

[Claims] (1) A cuprammonium regenerated cellulose hollow fiber membrane having an average pore diameter in the range of 0.02 to 0.2 μm (1) A module in which one to several membranes are housed in a cylinder (3),
At the end of the module, its cylinder (3) is open to atmospheric pressure and the membrane (1) is completely sealed;
On the other hand, at the other end of the module, a one-touch quick fluid coupling (plug) (4) is fixed to the membrane (1) and the cylinder (3) via a filler (2), and the membrane ( 1)
A module for particle separation microfiltration characterized by having an opening to the outside system.