JPS6012578Y2 - Fiber entanglement separation material - Google Patents

Description

[Detailed explanation of the invention] In recent years, with the development of hematology and immunology, instead of the conventional whole blood transfusion, transfusion of specific blood components such as granulocytes and lymphocytes among red blood cells and white blood cells has been introduced. Component blood transfusion, in which only blood is transfused to various patients, has come to be practiced.

This component transfusion has the great advantage that components unnecessary or harmful to the patient can be removed from the blood, and necessary components can be concentrated and transfused in large quantities.

Currently, common component transfusions include leukocyte transfusions and granulocyte transfusions for patients with abnormally low white blood cell counts and fever due to bacterial infection, and lymphocyte transfusions for various immunotherapies.

We also extract pure lymphocytes from blood and use this lymphocyte suspension to conduct research on histocompatibility antigens and cellular immunology, and to separate these lymphocytes into subpopulations such as T cells and B cells. Attempts to separate cells into sublets such as helper T cells and suppressor T cells are being considered at hospitals and research institutes across the country.

As a blood separation method that can be used for such purposes, separation methods using fiber aggregates have recently been in the spotlight in place of conventional hemagglutination methods, centrifugation methods, and electrophoresis methods.

For example, in JP-A No. 55-58166, in order to collect leukocytes including lymphocytes from a blood cell suspension with a simple operation and with a high yield, fibers with an average diameter of 7μ or more and 10μ or less are prepared from 0.04110111. 0.25 f/C1i
A white blood cell differential filter is disclosed that is packed in a container with a density range of 1.

The mechanism by which such thin fiber aggregates perform blood cell fractionation is currently not clear, but the surface characteristics of the fiber material and the spatial characteristics formed by the fiber aggregates are largely involved. considered to be a thing.

In particular, the spatial characteristics listed in 2 are important factors, and
No. 58166 discloses the need to fill a separation vessel with fine fibers at a suitable bulk density.

On the other hand, it is difficult to uniformly pack thin fibers into a separation container such as a column at a constant bulk density, resulting in uneven density inside the container, resulting in a lack of reproducibility in separation speed and yield. .

In order to improve this drawback, a method for collecting proteins was proposed in JP-A-54-36, in which a sheet-like structure made of an aggregate of thin fibers was prepared separately in advance and the structure was filled into a separation container.
No. 300.

The present invention is a further development and improvement of these prior art techniques, and relates to a fiber entanglement separation material that is excellent not only for protein collection but also for blood processing, blood cell separation, etc.

That is, the gist of the present invention is a binder-free nonwoven fabric made of short fibers with a single fineness of 1 denier or less, in which the short fibers do not adhere to each other by fusion, but are intertwined with each other. The strength is 30kp/cm/g/ad or more and 4001g/cm/fl/- or less, and the bulk density is 0.05El/ai1 or moreo, o5g/c
This is a fiber entanglement separation material characterized in that the fiber entanglement separation material is J or less.

It is known that aggregates of thin fibers are suitable for blood cell separation, but in reality, it is difficult to directly handle fibrous materials of 1 denier or less, and in practice, it is difficult to use such fibers as a separation material. It is necessary to form the material into some kind of tissue, especially a sheet-like material.

In this case, it is necessary that the sheet-like material has a certain strength.

Usually, spun fibers have a small amount of surfactant attached to them.
If this product is used as it is for blood treatment, phenomena such as hemolysis will occur, so the surfactant must be removed in advance.

Therefore, fiber sheets of 1 denier or less should be boiled,
The sheet material is often subjected to severe mechanical effects such as solvent treatment, so the sheet material must have a certain level of strength.

However, in order to give the sheet-like material strength, it is not possible to perform calender heat treatment to heat-fuse the fibers, or to add binder resin or binder fibers.
This is undesirable because it significantly reduces the surface area of the sheet fibers, reduces the contact area with the object to be treated, and changes the shape of the fiber surface from cylindrical to film-like, resulting in the destruction of blood cells.

The separator of the present invention solves these drawbacks and is a fiber entangled body that is formed by intertwining fibers without substantially melting or adhering to each other and having a strong and uniform bulk density. .

This fiber entanglement is generally in the form of a nonwoven fabric and can be easily produced by, for example, three steps.

First, fibers of 1 denier or less are made into short fibers with a fiber length of about 2 or less, and then put into a mixer or finer.
After the fibers have been thoroughly opened using a method such as the following, they are made into a wet web or paper.

Next, a plurality of sheets of the paper are laminated and treated with a high-pressure jet fluid from above to intertwine and integrate them into a nonwoven fabric.

Finally, the nonwoven fabric is subjected to shrinkage treatment using the heat shrinkability of the fibers, and is formed into a fabric having the desired date, bulk density, and strength.

In the present invention, it is necessary that the fineness of the short fibers be as fine as 1 denier or less, so that blood cells can be separated well.
In addition, intertwining between fibers is facilitated by fluid treatment.

Also, the nonwoven fabric strength is 30ko/cm/9/CF11
If it is less than that, the nonwoven fabric will break due to boiling treatment, which is not practical.

If the density of the nonwoven fabric is less than 0.05, it will not be able to withstand boiling treatment, and if it exceeds 0.50, the nonwoven fabric will become too dense, and proteins to be adsorbed and blood cells to be separated will not be uniformly dispersed within the nonwoven fabric. Undesirable.

As the fiber material used in the present invention, various synthetic fibers, natural fibers, and semi-natural fibers such as polyacrylonitrile-based, polyester-based, nylon-based, polyolefin-based, cellulose and cellulose derivatives can be used.

Among these, polyacrylonitrile synthetic fibers are particularly preferred materials because of their ability to adsorb proteins and their adhesive strength to blood cells.

The nonwoven fabric may be formed by using these fibers alone or by mixing them together.

FIG. 1 is a diagram schematically showing the fiber entanglement and separation material of the present invention, and its structure is formed by intertwining short fibers of 1 denier or less, indicated by A.

When the separating material according to the present invention is cut, the fibers do not fray from the cut end, and as shown in Figure 2, the fibers are not frayed.
It is extremely easy to cut into various shapes depending on the specific use, such as 1 square b1 triangle c1 donut shape d1 pastry shape e, etc.

For example, a circular filter as shown in Figure a can be incorporated into a suitable filter as a filter to pass through the liquid to be treated.

Alternatively, a filter unit can be formed by stacking a large number of them in a cylindrical column.

At this time, since the nonwoven fabric itself is formed to have a constant bulk density, the entire column becomes a filter unit having a uniform bulk density.

Using this column, a suspension of blood cell components is allowed to flow down from the top of the column, for example, only white blood cells are selectively trapped in the separation material, and after a washing solution consisting of physiological saline is allowed to flow down, a solution such as phosphate buffered saline containing serum albumin is added. Using the eluate, leukocytes can be collected without destroying the blood cells.

As explained above, the separation material of the present invention is made of an intertwined aggregate of thin short fibers, and has a uniform density and strength that makes it easy to handle, so it can be processed into any shape to form a filter unit. It can be usefully used as a separation material for blood cells and proteins.

[Brief explanation of drawings]

FIG. 1 schematically shows a separating material according to the present invention, and FIG. 2 shows examples in which the present invention is processed into various shapes. A: Short fibers of 1 denier or less.

Claims (1)

[Scope of utility model registration request] A binder-free nonwoven fabric made of acrylonitrile short fibers with a single fiber fineness of 1.0 denier or less, the short fibers do not fuse or adhere to each other, but are partially entangled with each other, and the nonwoven fabric has a strength of 30 9/cm/9/cy) or more 4
00ky/cm/y/crl or less, and its key density is 0.05p/cff1 or more 0.509/c11
A fiber entangling separation material for blood separation characterized by the following: