SI20011A - Structure of large-volume tubular module - Google Patents

Abstract

A structure of large-volume tubular modules offers a way of how to construct a tubular module of an optional volume with a homogeneous polymer structure. This very solution enables the application of tubular modules in industries where larger volumes of active material for preparative purification of biomolecules is required. The structure of large-volume tubular modules has been solved in such a way that thermal conductivity of a polymer mixture LambdaT and specific released heat S are calculated for a concrete system of the polymer mixture on the basis of the polymerisation temperature profile of the same polymer mixture within a rod. By the polymerisation of the same mixture at different temperatures, a maximal allowed temperature change to preserve the unchanged polymer structure is determined. The data obtained in this way are used to solve numerically the equation 1 or to solve analytically the equation 2 or, in the case of higher exterior thermal resistivities, to solve the appropriately modified equations. Thus, the maximal thickness of the polymer tube can be determined on the basis of a chosen exterior radius. The tubular module structure is carried out by preparation of several tubular polymeric pieces (1, 2, 3) of the precisely defined thickness having the same or different active chemical groups, which may be inserted one into another so that the exterior diameter of the inner tube is matching the inner diameter of the exterior tube (4). The accordingly prepared tubular module is then inserted into a respective casing.

Description

CONSTRUCTION OF LARGE VOLUME PIPE MODULE

The object of the invention is the construction of a bulk tube tube module useful for preparative separation and bioconversion.

The purification and isolation of molecules, especially biopolymers, is still one of the most expensive steps in their production. Biopolymers include oligopetides and polypeptides, proteins, enzymes, lectins, antibodies, nucleic acids, polysaccharides, oligonucleotides and polynucleotides.

There are more methods of cleaning than e.g. salting with neutral salts, by changing the pH value, by electrophoresis and by using chromatographic methods.

Probably the first protein separation was performed in 1954 (A.J.P. Martin and R.L.M. Synge, Biochem. J., 35 (1941) 1358) on DEAE pulp. Since then, there has been intensive development of both chromatographic carriers as well as various chemically active separation groups. At the end of the 1950s, Pharmacia (Uppsala, Sweden) introduced crosslinked dextran gel for so-called. gel-filtration (size-exclusion chromatography) for protein and nucleic acid separation (German patent 1,292,883; GB patent 974,054). Its use in chromatography was limited mainly by its low mechanical stability. In 1976, the first separation of peptides based on i.i. reverse phase chromatography (K. Tsuji, J. H. Robinson, J. Chromatogr., 112 (1976) 663), followed by many articles on protein separation by chromatography, both gel filtration, ion exchange chromatography, and reversed phase chromatography. . The mounting brackets used were mechanically very stable, allowing for high flow rates and thus shorter separation times. They had a spherical particle structure of about 10 to 100 pm in diameter with high porosity, which resulted in a large specific surface area and associated high biopolymer binding capacity.

Biopolymers are large molecules (typically some 10 to some 100 kDa), so their diffusion coefficient is low (order of magnitude 10 ' ⁷ m ² / s). Because most of the separation process takes place in the pores of the particle carriers within which the fluid is stationary, the molecules travel to the active surface on a diffusion basis, limiting the separation rate. Carriers of various structures have therefore been developed to address diffusion problems. The first such solution is represented by non-porous particles (see, for example, W.-C. Lee, J. Chromatogr. B, 699 (1997) 29), where the entire separation process takes place on the surface of the non-porous particle. This allows for extremely rapid analysis of biopolymers (several seconds), but their main disadvantage is the low specific surface area and therefore the low binding capacity. Another solution is represented by these flow particles (NB Afeyan, NF Gordon, I. Mazsaroff, L. Varady, SP Fulton, Υ.Β. Yang, FE Regnier, J. Chromatogr., 519 (1990) 1). Their feature is that they have flow pores in addition to closed pores. Unlike non-porous particles, they have a higher specific surface area and a binding capacity and better hydrodynamic properties than porous particles. However, since they have partial structures, there is still an empty space between the particles. This represents a lower resistance to the liquid, so most (over 90%) still flow around the particles. The next step in carrier development is represented by monoliths. Unlike the aforementioned particulate carriers, the monoliths consist of a single piece of porous polymeric material containing flow pores (US Patent 4,889,632; US Patent 4,923,610). Because there is no empty space inside the carrier, the entire fluid is forced to flow through the flow pores. They are characterized by the ability to quickly separate biopolymers (comparable to non-porous particles), low back pressure even at higher flow rates and high capacity. Their use in industrial applications has so far been limited by the difficulty of preparing a monolith with a homogeneous structure of larger dimensions, as well as poorer mechanical stability. Solutions to these two problems are the subject of this patent.

Pipe modules are constructed of a housing described in detail in patent application no. P9800058 providing mechanical stability and good distribution and a porous polymer in the form of a multilayer tube. Each layer is a monolithic porous polymer containing small pores with diameters below 200 nm as well as large pores up to 2500 nm in diameter.

The porosity of the monolithic porous polymer is between 30 and 90%. Monolithic porous polymer includes a polymer of polyvinyl monomer selected from divimlbenzene, divinylnaphthalene, divinylpyridine, alkylene dimethacrylate, alkylene diacrylate, hydroxyalkylene dimethacrylate, hydroxyalkylene dietriethyletherylethyl erylethyl ether, ethyl acetate, oleocrystalline ethylene acetate, ethylene glycol diethyl acetate; acrylate, trimethyloylpropane trimethacrylate or acrylate, alkylene bis acrylamide or methacrylamide or mixtures thereof.

The monolithic porous copolymer includes, in addition to the polyvinyl monomer, the monovinyl monomer. The latter is selected from the group consisting of styrene, ring-substituted styrene, vinyl naphthalene, acrylates, methacrylates, vinyl acetate, vinylpyrrolidone or a mixture thereof.

In addition to the monomers, the initial monomeme mixture contains a radical initiator, which, together with the monomers, is dissolved in an inert organic solvent from the group of alcohols, carboxylic acid esters or ketones, or combinations thereof, to achieve different porosity of the final polymer.

The radical initiator is selected from the group of azo compounds, peroxides, hydroperoxides, redox systems or the like.

Reactive chemical groups can be introduced into the monolithic porous polymer by chemical modification. allyl, amino, sulfonate, hydrogen sulfonate, hydroxyl, or alkyl lengths up to 18 atoms. We can also immobilize different ligands, such as e.g. peptides, proteins, oligonucleotides, etc.

The working volume of the tube module described in patent application no. The P-9800058 is too small to be used in most industrial processes. In the case of a tube module, the volume can be increased in two ways: by extending the tube module or by increasing its diameter. Although, from the standpoint of separation quality, the first option is more appropriate, we should be aware that the volume increases linearly with length, while increasing in diameter increases with the square. An additional problem with the extension of the pipe module is the uneven distribution of the sample, since the path that the sample has to travel in order to cover the entire surface from the beginning to the end of the pipe module is very long. It inevitably follows that further enlargement, at least to some extent, must be based on an increase in diameter.

This raises the problem of ensuring the homogeneity of the polymer structure. Polymerization is an exothermic process. In the case of suspension polymerization, this phenomenon is not particularly problematic as mixing is present, while the droplets within which the polymerization takes place are small. The polymerization of larger tube modules, however, generates a greater amount of heat, which results in the creation of a temperature profile within the polymerization solution. The polymerization of the monolithic porous polymer from which the tube modules are made can result in a gel effect, which makes the heat generation even greater in the short term. Since the structure of the pore distribution is highly dependent on temperature, the preparation of a polymer with a homogeneous structure determines the upper temperature within the polymer mixture, which must not be exceeded during polymerization.

Also, resting of the monomial mixture is required to establish a controlled structure. It follows that the temperature profile within the polymer during the polymerization will depend on the amount of specific heat generated, the thermal conductivity of the polymer mixture, and the thickness of the polymer layer. Since the first two factors are the characteristics of a particular polymer system, they cannot be influenced. Therefore, it is necessary to determine the thickness of the layer within which the temperature change is low enough that it does not affect the homogeneity of the polymer structure. The maximum temperature inside a monolithic porous polymer, which has the form of a tube thermostated to the internal and external polymerization temperature at a given internal and external radius, is calculated on the basis of the thermal conductivity of the polymer mixture and the specific heat released on the basis of the equation:

τ = τ + ¹ max ^Α 0 ^τ

4/1,

f / \ 2) - ln k ( _r λ -1 2ln - v kV) J

(1) r '- inside diameter (m) r _z - outside diameter (m)

T _o - polymerization temperature (K)

T _max - maximum temperature reached within the polymer (K)

S - specific released heat (W / m) λτ - thermal conductivity of the polymer mixture (W / mK)

In cases where the diameter is large enough that the error is acceptable, the equation for a flat plate can be used instead of equation 1, which reads as follows:

= T in

S ·

2-2 _T

(2)

The above two equations do not include the external thermal resistance of the model in which the polymerization takes place, nor the thermal resistance of the boundary layer of the medium into which the model with the monomer mixture is inserted. If these resistances are significant, the above equations must be modified accordingly.

From Equations 1 and 2, for the prescribed maximum temperature, the maximum thickness of the polymer layer can be determined.

According to the invention, the construction of a larger volume tube module is solved by calculating the thermal conductivity (λτ) and the specific heat released (S) for a particular system of monomer mixture during polymerization at the moment when the maximum temperature is reached. By polymerizing the same mixture at different temperatures, we determine the maximum allowable temperature change that maintains the desired structure of the monolithic porous polymer. The data thus obtained can be used to solve Equations 1 or 2, or in the case of large external thermal resistances of the modified equations. The thickness of the monolithic porous polymer tube is determined on the basis of the selected external radius. The construction of the tube module is shown in Figure 1 and is made by preparing several monolithic porous polymer pieces in the form of tubes (1,2,3), with a precisely defined thickness, so that they can be inserted into each other, so that the outer diameter is internally pipe fits inside diameter of outer tube (4). Although only three layers are shown, the module can be constructed from any Number of layers.

The multilayer tube module thus prepared is inserted into the corresponding large housing described in detail in patent application P-9800058. As the number of layers is not limited by this method of preparation, a CIM pipe module of any volume can be prepared.

Aleš ŠTRANCAR for BIA d.o.o

Claims (8)

PATENT APPLICATION 1. Large volume tube module construction characterized by the insertion of a multilayer porous polymer tube into a suitable housing. 2. The construction of a larger volume tube module, characterized in that the multilayer porous polymer tube is made up of any number of monolithic porous polymer tubes of precisely defined thickness, so that they can be inserted into one another and fit snugly between them; they form a multilayer porous tube with an inner diameter equal to the pipe with the smallest inside diameter and an outer diameter equal to the pipe with the largest outer diameter. 3. Bulk tube module construction characterized in that each multilayer porous polymer tube contains at least one functional group that may be the same for all monolithic porous tubes, or different monolithic porous tubes may have different functional groups that may be classified within a multilayer porous tube. porous polymer tubes in any combination. 4. Bulk tube module construction characterized in that the thickness of the monolithic porous polymer tube is less than or at most equal to the thickness calculated for a particular system of polyvinyl monomer, monovinyl monomer, initiator and porogens by determining the thermal conductivity of the polymer during polymerization (λ _τ ), the specific heat released (S), and the maximum allowable temperature change that maintains the desired polymer structure, based on Equations 1 or 2, or modified equations accordingly. 5. Bulk tube module construction characterized in that the monolithic porous polymer tube contains a polyvinyl monomer polymer selected from divinylbenzene, divinylnaphthalene, divinylpyridine, alkylene dimethacrylate, alkylene diacrylate, hydroxyalkylene dimethacrylate, hydroxyalkylene dimethacrylate, hydroxyalkylene dimethacrylate, hydroxyalkylene dimethacrylate, , polycarboxylic acid vinyl ester, divinyl ether, pentaerythritol di-, tri- or tetramethacrylate or acrylate, trimethyloylpropane trimethacrylate or acrylate, alkylene bis acrylamide or methacrylamide or mixtures thereof. 6. Bulk tube module construction characterized in that the monolithic porous polymer tube comprises a monovinyl monomer polymer selected from the group consisting of styrene, ring-substituted styrene, vinylnaphthalene, acrylates, methacrylates, vinyl acetate, vinylpyrrolidone or a mixture thereof. 7. Large volume tube module construction characterized in that the monolithic porous polymer tube contains small pores with diameters below 200 nm as well as large pores with diameters greater than 600 nm and up to 2500 nm. 8. Large volume tube module construction characterized in that the porosity of the monolithic porous polymer tube is between 30 and 90%.