CS244828B2 - Production method of polyakrylamide cement for stabilization fine-grain sorption layers - Google Patents

Abstract

Process for producing a polyacrylamide binder suitable for fixing fine grained marrows layers with a particle size range 2 to 20 µm and especially with a narrow size range particles in the Δ / im <2 range based on organic and / or inorganic substances and / or with optionally bound apolar phase for pressurized single layer and multi layer chromatography, characterized in that it is made of polyacrylanide pile foundation from a mixture of 1.6 to 2.5% aqueous acrylamide solution and 0.6 to 1.0% aqueous solution -methylene-bis-acrylamide by the action of catalysts, as Ν, Ν, Μ ', Ν'-tetramethylethylenediamine and amine peroxydisulfate at temperature between 21 and 30 ° C after solvent homogenization water soluble, precipitated with acetone, methanol or ethanol fraction suitable as a binder, the precipitate obtained is then by water treatment and then process clotting and clogging at least once.

Description

Process for the production of a polyacrylamide binder suitable for fixing fine-grained sunny layers having a particle size range of 2 to 20 µm and in particular with a narrow particle size range in the range of Δ / im <2 based on organic and / or inorganic substances and / or with an apolar phase Single-layer and multi-layer chromatography, characterized in that from a polyacrylanide pellet base formed from a mixture of 1.6 to 2.5% aqueous acrylamide solution and 0.6 to 1.0% aqueous methylene-bis-acrylamide solution by treatment with catalysts, such as Ν, Ν, Μ ', Ν'-tetramethylethylenediamine and amino peroxydisulfate at a temperature between 21 and 30 ° C after homogenization with a water-soluble solvent, precipitates a fraction suitable as binder with acetone, methanol or ethanol, then precipitates the resulting precipitate with water the precipitation and liquefaction process is repeated at least once.

The present invention relates to a process for the production of a polyacrylamide binder for fixing fine-grained sorbent layers with special properties suitable for correspondingly fixing fine-grained sorbent layers with special properties suitable for correspondingly fixing fine-grained sorbents (particularly with a narrow particle size range) consisting of organic base materials / celluloses, synthetic polyamide resin, etc./ or / and organic base materials (silica gel, alumina or silica gel provided with a chemically bonded and / or non-binding apolar phase, etc.) and mixtures thereof on different carrier plates and which is applicable to a monolayer and multilayer chromatography.

Comparison of the developmental directions of laboratory instrumentation shows today the unequivocal growth of chromatographic techniques and this tendency may become even more pronounced in the coming years. This is particularly true of the liquid chromatography method working with the column system and planar arrangement.

The variants of the so-called high-performance liquid chromatography (abbreviated to HPLC by English name) already occupy a leading position in the analysis of various groups of compounds due to their efficacy, but their preparative use is also important / see Engelhardt: Hochdruck-Flussigkeitschromatographie, 2 Edition, Springer-Verlag, Berlin-Heidelberg-New York, 1977 /.

The development of high performance liquid chromatography and the results obtained with this method also require a fundamental renewal of the most widely used plane chromatography liquid chromatography technique, i.e., layer chromatography.

The disadvantage of classical layer chromatography (in which the mobile phase (solvent mixture) migrates to anchored or stationary phase (to a mixture of solvents or adsorbents) and carries with it one or more substances at different speeds is that the development time is long and for a short layer spacing on the board, the division is not always complete and the theoretical number of backers is limited.

the development of high performance layer chromatography (HPTLC) represents a significant advance (A). Zlatkis and RE Kaisers High-Performance Thin-Layer Chromatography, Elsevier, 1977s and W. Bertsch, S. Hara, RE Kaiser and A. Zlatkis: Instrumental HPTLC, Huthig, Heidelberg, 1980 /) The most important characteristic of this layered chormatography is the use of fine-grained adsorbents on plates and instrumentation.

The well-known fact that HPTLC can achieve an effective distribution on a fine-grained (e.g. 5 µm) layer, but also points to the limits of this technique, since good distribution can only be achieved over short distances while longer development distances (e.g. 15 to 20 cm / sec - due to the slowing of the solvent stream - increases diffusion and stains (or streaks) to stretch.

It was therefore logical to consider the development of a technique that approximated well-standardizable column chromatography ratios while maintaining the indispensable advantages of layer chromatography / the possibility of visual evaluation, the possibility of using aggressive reagents, identification by map method, etc./.

These requirements are met by high-pressure layer chromatography (OPLC), which combines the advantages of classical layer chromatography (TLC), high-performance layer chromatography (HPTLC) / this technique is based primarily on the use of fine-grained layers on plates / and high performance liquid chromatography (HPLC).

The basic apparatus is a pressurized ultramic micro chamber in which a layer of sorbents (e.g. silica gel, alumina, talc, etc.) is preferably pressed by the pressure - through a flexible membrane - maintained by the aqueous cushion system in the chamber, thereby eliminating the vapor space above the layer.

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The feed micro-pump feeds the eluent through a controlled pressure flow to the sorbent layer / cf. U.S. Patent No. 173,749, British Patent No. 6,170,760, and U.S. Patent No. 4,346,001.

By varying the location of the eluent inlet openings, there is the possibility of developing in one 61 two directions as well as linear, circulating, triangular (anticirculating).

When using efficient, linear high pressure layer chromatography (OPLC), the edge of the sorbent layers must be closed, most effectively by impregnation or coating with a plastic film layer, so that the eluent cannot escape due to the positive pressure.

Linear face migration of the eluent can be provided by a channel around the eluent inlet or by attaching a wire (plastic plate). According to the novel method, a sliding plate (which, moreover, protects the cushion of the water system, is replaceable, etc.) is placed on the sorbent layer on the carrier plate, on which it is in the part around the eluent inlet on the sorbent side providing one or more eluent channels.

Recently, it has been found that a high-pressure ultramic Micro chamber is suitable for developing simultaneously on several layers. If the layer support plates are especially adapted for this purpose, they are perforated in any shape and size around the point of the eluent feed to the layer.

The layers on the plates perforated in this way can be placed together with the layer on the plate, the edges of which are closed in the usual way, into one system, which then becomes suitable for developing different types as well as for analyzing in particular several samples at the same time. This is then high pressure multilayer chromatography.

Adhesives based on a variety of raw materials are used to fix the sorbent layer of the finished layers to plates in the case of classical layer chromatography (TLC) and high performance layer chromatography, particularly those which are resistant to aggressive reagents and which are relatively inert.

For the group of conventional fixatives or adhesives used so far (for example agar-agar, starch, polyvinyl alcohol, binder vinyl acetate), it is typical that these substances are sensitive to aggressive reagents, especially in aqueous systems they partially dissolve and their use is now overcome. . for example, German Patent Specification No. 1,442,446, pp. 7-8, Hungarian Patent Specification No. 161,267 /.

Instead of these, inert adhesives based on organic polymers or inorganic adhesives are used which resist aqueous systems, organic solvents and, in part, also aggressive agents. In German Patent 1,442,446, acrylic and methacrylic acid polymers or their salts or copolymers of ethylene and maleic acid or their salts with a high degree of polyraeration are used as binders.

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In German Patent No. 1,517, various and inorganic substances, various and their derivatives.

929 is used for fixation of sorbents based on organic type, polyacrylamide or polymethacrylamide

In German Patent No. 1,915,963, alkali metal silicate is again used as a binder. However, these organic raw material adhesives have the disadvantage that they are not always sufficiently resistant especially to aggressive agents (e.g. sulfuric acid), especially at high development temperatures, become discolored, and furthermore, such an important reaction as ninhydrin occurs between these adhesives. reaction, in that the quantitative evaluation then encounters difficulties. For alkali metal silicate adhesives, it is difficult to provide staged conditions.

Because of these disadvantages, these adhesives are therefore unsuitable for the production of layers on high pressure chromatography (OPLC) plates. The following claims must be made for adhesives usable for these purposes:

1. In a multi-layer or multi-layer high-pressure chromatography, the solvent mixture is forced upstream (via a feed pump), such viscous solvent mixtures (aqueous buffers, etc.) may be used, and the adhesive or the layer fixed thereto must withstand these aqueous viscous mixtures and must not dissolve or break, etc.

2. In a pressurized ultramarine chamber, the layer on the plate is simultaneously exposed to a significant external pressure and therefore the bonding of the sorbent layer must withstand this pressure.

3. The mild sensitivity of the adhesive to the ninhydrin reaction is particularly important because high pressure chromatography on one and several layers is particularly advantageous in quantitative analysis of amino acids and peptides. In particular, the importance of evidence of amino acid traces (for example, N ^c- methylated lysine) that disappear on a case-by-case basis on a light violet background should be emphasized.

4. Requirements for high-pressure monolayer and multilayer chromatography also include solving side-by-side gluing of fine-grained sorbents whose particle size is within a narrow range and are based on organic and inorganic substances, as well as safe bonding of any sorbent-based sorbent mixture organic and inorganic substances, ie substances from different sources, and the other properties of the substances must not affect the bonding process.

5. A considerable advantage of high pressure single layer and multilayer chromatography is that it is also suitable for the use of particularly fine-grained (e.g. 3-5 µm) and especially thin (film-like) (e.g., 45 µm thick) layers of sorbent on the plates, at the same time, it allows a division that is superior to all previous ones. The adhesive must therefore also be suitable for bonding such sorbents.

6. For high-pressure monolayer and multilayer chromatography, the basic requirement is, regardless of the particle size, to use layers on the plates where the sorbent particle size falls within a narrow range because, due to forced flow of solvent, uneven local flow between particles the particles differ substantially in particle size, due to increased longitudinal diffusion. However, fixing such sorbents is more difficult than fixing sorbents of different sizes, but the adhesive must also be suitable for this purpose.

7. The undisputed disadvantage of the finished layers and boards compared to the filled columns is that the presence of the adhesive used to fix the sorbent layers reduces the efficiency of the development process and, in particular, the plausibility of the measured values. A binder is therefore required which, even in small quantities, ensures the desired degree of fixation.

8. Temperature plays a particularly important role in the efficiency of high-pressure single-layer and multi-layer chromatography separation. The optimum temperature value is always somewhat different and can be both high / low. It is therefore expedient to produce a binder that is equally stable to the corresponding plate (e.g., aluminum foil) and the cover plate (e.g., teflon) in the temperature range between +5 and +120 ° C.

SUMMARY OF THE INVENTION It was an object of the present invention to provide a binder for the production of TLC- and HPTLC-chromatogthia plates which overcomes the drawbacks of the known and used binders and which satisfies the special requirements for high-pressure single layer and multilayer chromatography mentioned above.

The present invention is based on the finding that the binding ability of polyacrylamide gels produced in different ways to sorbent varies depending on the quality, the amount of scaffold-forming monomer as well as the polymerization temperature, and that the monomers and oligomers remaining in the gel skeleton adversely affect the binding ability and the different surface properties of the polyacrylamide, and therefore must be removed from the polyacrylamide gel in order to achieve the desired goal.

Furthermore, it has been found that the fraction suitable for binding the sorbent layer is precipitated from a gel skeleton produced and homogenized in a controlled temperature range by a solvent insoluble. in water, preferably acetone, and that this fraction can be easily separated from monomers and oligomers which adversely affect the properties of the binder.

Accordingly, it is an object of the present invention to provide a process for preparing a polyacrylamide binder for fixing fine-grained sorbent layers having a particle size range of 2 to 20 µm and in particular with a narrow particle size range of 4> µm <2 based on organic and / or inorganic substances and / Apolar phase for pressurized monolayer and multilayer chromatography, characterized in that from a polyacrylamide gel base formed from a mixture of 1.6 to 2.5% (in the text,% by weight, unless otherwise stated) of an aqueous acrylamide solution is indicated and 0.6 to 1.0% aqueous solution of Ν, Ν'-methylene-bis-skrylamide by treatment with catalysts such as Ν, Ν, Ν ', Ν'-tetramethylethylemdiamine and ammonium peroxydisulfate at a temperature between 21 and 30 ° C after homogenization with a solvent soluble solvent in water, a fraction suitable as a binder precipitates with acetone, methanol or ethanol, and the resulting precipitate is then spoiled by the action of water and then the precipitation and liquefaction process is repeated at least once.

The polyacrylamide gel binder prepared by the process of the invention is suitable for fixing the sorbent layers for high pressure single layer and multilayer chromatography. The specific mass of the binder is between 1.004 and 1,008 g / ml, a viscosity Ί _rel between 2 and 20, resistant to most water insoluble aggressive agents impermeable to water / example to a hydrogen vanillin / not sensitive to ninhydrin »sorption layers prepared with such binders they are also not sensitive to the effect of external and internal pressure measurable in the pressurized cloud chamber as well as to the higher temperatures used in the development process.

Such binders retain their original form and are also suitable for bonding fine-grained and narrow particle sizes of sorbents based on organic and / or inorganic substances as well as mixtures thereof.

The binder-fixed sorbent layers produced by the process of the present invention meet the requirements for quantitative evaluation better than the sorbent layers made using previously known and used binders.

In the process according to the invention, Ν, Ν, Ν ', Ν'-tetramethylethylenediamine (TEMED) is added to the aqueous solution of acrylamide and N, N'-methylene-bis-acrylamide, then another catalyst, preferably ammonium peroxydisulfate, is added in the temperature range 21 to 30 ° C and the obtained polyacrylamide gel is homogenized in a homogenizer.

A liquid opal solution is thus obtained. 7 of this solution, the addition of a water-soluble solvent, preferably acetone, yields a curd-like precipitate which, after the solvent has been released by addition of the original amount of water, is retested, and this step is repeated several times as necessary.

The opal aqueous solution which is formed during the last transfer of the curd precipitate to the slurry by the action of water is an adhesive solution.

In the following, preferred embodiments of the process according to the invention are described.

A very preferred variant of the process according to the invention is based on a 2.0% aqueous solution based on acrylamide and a 0.8% aqueous solution based on N, N'-methylene-bis-acrylamide.

The catalyst used is preferably N, N, N *, N'-tetramethylethylenediamine (TEMED) together with ammonium peroxydisulfate (NH4), although other pairs of compounds may also be used as the catalyst, such as ammonium peroxydisulfate and 3-dimethylaminopropionitrile; ribeflavin and Ν, Ν, Ν ', Ν'-tetramethylethylenediamine.

Ν, Ν, Ν ', Ν'-Tetramethylethylenediamine (TEMED) is added directly to the reaction mixture, while the ammonium peroxydisulfate is dissolved in a few ml of water and this solution is added dropwise in the middle of the first vigorously stirred solution.

Stirring then ceases itself. Ammonium peroxydisulfate can also be added to the solution in the solid state. Here, too, mixing stops. Tanning starts after 4 to 5 minutes and generally stops after 30 minutes.

The temperature of the gelling process is expediently selected such that it starts at a temperature of 22 to 23 ° C and can be raised to a maximum of 28 to 30 ° C.

The solidified gel is liquefied in a Waring mixer for up to 5 seconds and then the liquid opal solution thus obtained is suitable for solvent fractionation.

Valuable large molecules can precipitate from an opalized, liquefied gel solution with a water-soluble solvent such as acetone, methanol, ethanol, etc., but small molecules remain in solution.

In the case of the most useful solvent, i.e. acetone, the most favorable ratio of opal solution: acetone is 1: 1 (v / v).

Suitably, the curd precipitate precipitated with acetone is in each case converted for 30 seconds into a slurry by the action of water. Addition of acetone generates heat and thus the solution is separated by decantation by cooling.

The quality of the adhesive is better the more frequently the shrinking process is repeated. However, it is expedient to carry out the precipitation three times.

The polyacrylamide content of the opal solution is between 1.6 and 2.2. Based on this fact, the percentage of adhesive per sorbent is calculated. Depending on the type of adorbent and the thickness of the layer, this amount is suitably between 0.5 and 5.0%.

The following examples illustrate the process according to the invention. However, these examples do not limit the scope of the invention in any way.

He did

A / Production of polyacrylamide g g acrylamide and 8 g N, N'-methylene-bis-acrylamide are dissolved in 1000 ml of distilled water. 3 ml of Ν, Ν, Ν ', π'-tetramethylethylenediamine (TEMED) are added to the solution and the aqueous solution adjusted to 22.5 ° C is mixed thoroughly by stirring in one direction, then solution 0 is added to the previously stirred solution. 8 g (NH 4) 3 in water (3 ml).

After 4 minutes, the tanning starts, the temperature of the mixture is raised to 29 ° C and after 30 minutes the gelling process stops.

The gel was then liquefied in a Waring blender for 5 seconds and then 1000 ml of acetone was added to 1000 ml of the opal solution. The solution is decanted off by cooling and the isolated curd precipitate, together with the precipitate precipitated on the vessel wall, is taken up with 1000 ml of water and the mixture is slurried for 30 seconds. To the opal solution thus obtained, 1000 ml of acetone are again added, the previous step is repeated, i.e. precipitation with acetone is carried out again. / Decantation solutions are always set aside./

The polyacrylamide content of 1000 ml of the opal solution obtained in the last step is 0.021 g / ml, specific weight: 1.004 g / ml and η _re ^ 4.65.

B / Production of sorbent layers

Using the adhesive produced in accordance with paragraph A /, apply the following layer:

To 44 g of silica gel with an average particle size of 6 _[ mu] m and an inner diameter of 90.10 ^-10 m was added 57 ml of adhesive diluted with 87.5 ml of water (2.7% based on silica gel). The slurry thus obtained is mixed thoroughly and is fermented in a Waring mixer for 60 seconds.

The cream slurry thus obtained is applied by continuous coating to an aluminum foil with a thickness of 0.1 mm until a layer with a thickness of 0.2 mm is obtained. After drying, a layer of 0.16 mm thickness is obtained. After folding, 7 layers were obtained on 20 x 20 cm boards.

(C) Developing by high pressure chromatography on one layer of one of the layers on the plate produced in accordance with paragraph B), the adaorbent is scratched off on three sides at a width of 5 mm and containing a plastic dispersion (containing polyvinyl acetate and polyacrylamide). resistant to water and solvents.

3.0 cm from the imperfect edge, at a distance of 9 mm, 15 test dyes (CAMAG II product) are applied in equal quantities. After drying of the sample application sites, the plate is placed in an overpressure ultra-micro chamber (type Chrompres 10) provided with a slip-on plate with a Teflon channel to guide the solvent.

The cushion pressure was 1.2 Pa, the solvent flow rate was 185 ml / h, the solvent was methylene chloride and the evolution time was 4.6 minutes. The chromatogram obtained is evaluated using a chromatogram-spectrophotometer and a deviation of -1.5% was observed for each dye.

D / Pressurized multi-layer / four-layer / chromatography development

From the layers on the board prepared according to B), four layers on the boards are impregnated at their three edges with a width of 5 mm each of the dispersion plastic to form a water and solvent resistant plastic film, the film being subjected to a temperature of 100 °. c for 10 minutes.

Of the 4 layers on the impregnated edge boards, the top three at a distance of 15 mm from the indirectly closed edge are perforated in a width of 185 mm through an opening having a cross-section of 2 mm. On three similarly prepared perforated layers on the plates, a petroleum ether extract obtained from flowers of 3 x 15 chamomile plants is applied at a distance of 9 mm at a distance of 9 mm at a distance of 9 mm from the perforated column.

To dry the sites to which the samples have been applied, the plates are placed exactly on top of each other, with the bottom plate not being a perforated edge plate, but a fourth impregnated edge plate. This plate is also provided with extracts of other camomile extract 15.

The treated system is placed in a CHROMPRES 10 ultra-high pressure chamber.

Benzene is used for developing, the pressure of the pad is 1.1 MPa, the developing time is 16.2 minutes. After development, the plates are removed, dried and sprayed with a solution of 90% sulfuric acid containing 0.2% vanillin, then heated at 105 ° C for 5 minutes, then visualized and chromatographed with a spectrophotometer. On the layers it was possible to observe the same face distance and the same R ^ values with the scattering within the acceptable limits.

Example 2

The layers of silica gel applied as described in Example 1 were cut into 20 cm and 40 cm pieces. from the opposite sides of these layers on the plates, the adsorbent is scraped off at a width of 5 mm each, and at this point a plastic film is formed by means of a plastic dispersion for bi-directional overpressure chromatography on a water and solvent resistant layer.

A solvent control channel is formed in the middle of the layer at a width of 180 mm, while an aliquot of 15 different wheat protein hydrolysates is applied at 15 mm from each side of the channel, at a distance of 9 mm.

After drying of the non-sampled areas, the layer is placed in a CHROMPRES 10 pressurized ultramic chamber. The cushion pressure is 1.2 flPa. Developed using a 4: 1: 1 mixture of n-butanol, glacial acetic acid and water. The development time is 68 minutes.

After developing, the plate is dried and then sprayed with a ninhydrin reagent saturated with copper sulfate and containing 0.2% methanol / acetic acid. The plate is heated and then the color chromatogram is evaluated in an ohromatogram spectrophotometer.

Example 3

Using the binder described in Example 1, the following layer is applied:

g of talc with an average particle size of 3 to 4 µm is mixed with 40 ml of binder, which has been diluted with 40 ml of distilled water, stirred for 75 seconds in a Waring mixer, and then the resulting cream slurry is applied at a thickness of 0.15 m on terephthalate plastic foil of 0.15 mm thickness by continuous coating.

Thus, after drying, a talc layer of 0.1 mm thickness is obtained. After folding, 6 finished layers were obtained on 20 x 20 cm boards. On the three sides of the layers thus produced, the adsorbent is scraped off at a width of 5 mm and a plastic dispersion resistant to water and solvents is formed with a felt dispersion (containing polyvinyl acetate and polyacrylamide).

On one of the finished plates having an impregnated edge, plant extracts of Digitalis / Digitalis and authentic cardiac glycosides of the Foxglove in methanol-chloroform solution are applied. The layer is then placed in an ultra microchamber of the CHROMPRES 10 type.

A mixture of methyl ethyl ketone and water in a ratio of 18; 85. The development time is 25 minutes.

After drying, the layer was sprayed with a 20% aqueous phosphoric acid solution and heated at 120 ° C for 20 minutes. Yellowish-green spots are obtained and evaluated qualitatively and quantitatively.

He attaches

By means of the binder described in Example 1, a densified zone layer is formed:

In a large vessel (with a wider application area) with a specially treated application head, a suspension of 33 g of silica gel having an average particle size of 6 µm and an inner diameter of 90 is poured. ΙΟ ^-1 ®! »And 43 ml of binder diluted with 66 ml of distilled water (2.7% based on silica gel) after adequate fermentation.

In a smaller vessel (with smaller application area) a slurry of 11 q of kieselguhr having an average particle size of 15 µm and 15 ml of binder diluted with 21.5 ml of water is placed. These two types of slurries are applied to a 0.1 mm thick aluminum foil by continuous coating at a thickness of 0.1 nm.

After drying, a densified zone layer of 0.08 mm thickness is obtained, with a 4 cm wide strip of inactive kieselguhr and a 16 mm wide strip of active, fine-grained silica gel.

After cutting, 10 layers are obtained on 20 x 20 cm plates, the edges of which are impregnated for the purpose of the overpressure single layer chromatography according to Example 1. Camomile oils of different origin were used for separation, the components / polyins, sesquiterpene alcohols, etc. sharp stripes.

Example 5

Using a binder as described in Example 1, a mixed layer of silica gel and resin J was prepared

·. 28 g of silica gel with an average particle size of 6 µm and 16 g of strong cation exchange resin with an average particle size of 5 to 8 µm were mixed with 42.5 ml of binder and 70 ml of distilled water over 60 seconds to form a slurry.

The resulting slurry is applied to a 0.1 mm thick aluminum foil by continuous coating until a 0.2 mm thick layer is formed. This gives a 0.17 mm thick smooth light yellow layer.

After cutting, 7 layers are obtained on 20 x 20 cm boards.

For the purpose of overpressure monolayer and multilayer chromatography, the edges of the layers are impregnated or perforated as described in Example 1.

To demonstrate the effectiveness of the layers, samples of hydrolysates of different plant proteins and authentic mixtures of amino acids in hydrochloric acid are applied to the layers. After drying, the layer is placed in a CHROMOPRES 10 chamber.

An oitrate buffer mixture of pH 3.45 was used as developing solvent. Detection was performed using a ninhydrin reagent containing 0.2% methanol / acetic acid.

Example 6 g of acrylamide and 8 g of Ν, Ν'-methylene-bis-acrylamide are dissolved in 000 ml of distilled water. To the solution was added 2.8 ml of TEMED, and the aqueous solution thermostatted at 23 ° C, thoroughly mixed by stirring in one direction and then in the middle slurried sprinkled into the mixture a solution of 0.9 g of crystalline / NH _4/2 s ₂ 0 g. Tanning starts after 5 minutes, the gelling process is completed after 30 minutes.

The gel was then further processed as described in Example 1. The specific weight of the obtained binder solution makes opal 1,005 g / ml and a viscosity of _re ^ 1} is 6.8.

Using this binder, apply the following layer:

g of silica gel having an average particle size of 3 µm and an inner diameter of 60. 10 ~ ¹⁰ m together with 56 ml of binder diluted with 90 ml of water are mixed in a Waring mixer to a slurry. This slurry is then applied to an aluminum foil with a thickness of 0.1 m by continuous coating until a layer with a thickness of 0.1 mm is formed.

A layer of 0.06 mm thickness is obtained after drying. The individual pieces, after cutting, are impregnated at the edges and dyes for a single layer chromatography system are used for testing, in which particularly small amounts of samples (e.g. 5 to 10 µg) are applied to the layer.

Example 7

Using the binder described in Example 6, the following layer is formed:

g of alumina with an average particle size of 10 µm is mixed with a mixture of 39 ml of water and 28 ml of binder for 224 seconds to give a slurry. The slurry is then applied to 20 mm by 20 cm glass plates with a thickness of 2 mm by coating until a thickness of 0.2 mm is obtained.

Thus, after drying, an alumina layer having a thickness of 0.16 mm is obtained.

The edges of the layers on the plates, which were activated at a temperature of 110 [deg.] C., are scratched off on three sides at a width of 4 mm and a plastic film closure is formed there by means of a plastic dispersion.

Pure alkaloid-containing extracts made from one poppy were applied to the treated layers on the plates 3 cm from the untreated impregnated edge in a 1: 1 solution in methanol / chloroform as a 1: 1 solution.

After drying the sample sites, the plate with the corresponding plastic protective frame (to protect the cushion water system in the pressurized ultra-micro chamber against the cutting effect of the glass plate edges) is placed in the ultra-micro chamber CHROMPBES 10.

The cushion pressure is 1.2 MPa. A 40:50:10 mixture of heptane, chloroform and ether was used as eluent and after development, a Dragendorff reagent (according to Vagujfalvi) was used for detection.

Example

Using a binder as described in Example 6, a layer similar to the silica gel layer described therein is applied by preparing a slurry of silica gel supplemented with 1.8 wt. of manganese-activated zinc silicate as a UV indicator, based on silica gel.

Example 9 g of acrylamide and 16.2 g of N, N'-methylene-bis-acrylamide are dissolved in 2000 ml of distilled water. 4 ml of 3-dimethylaminopropionitrile was added to the obtained solution, and the aqueous solution was heated to 22 [deg.] C. and stirred vigorously in one direction.

Then a solution of 1.0 g (NH 4) 5 O 5 in 3 ml of distilled water is quickly added by dropping the solution into the center of the stirred solution. Tanning begins after 8 minutes, the gelling process is complete after 45 minutes.

The gel thus obtained is further processed as described in Example 1. The density of the opal binder solution obtained is 1.006 g / ml and the value is 4.3.

Using this binder, apply the following layer:

g of very pure cellulose with an average particle size of 5 .mu.m is mixed with 30 ml of binder diluted with 30 ml of distilled water. The slurry is applied to a 0.9 mm thick aluminum foil by conventional coating until a 0.15 mm thick layer is formed. '

The edges of the slit plates are impregnated as described in Example 1 and the plates are used to test amino acids in a positive pressure single layer chromatography system. A 3: 4: 1: 2 mixture of methyl ethyl ketone, acetonitrile, acetic acid and water was used as the developing solvent mixture. The external pressure of the cushion was 1.4 MPa, the development time (when over-puffed) was 59 minutes.

Example 10

The binder described in Example 9 is used to fix silica gel provided with chemically bonded stationary phase (silica gel RP-18) to an aluminum foil:

g of C-18 reverse phase powdered silica are mixed with 80 ml of polyacrylamide binder and 60 ml of isopropyl alcohol and the mixture is converted to a slurry within 175 seconds. The slurry obtained is applied by coating on an aluminum foil with a thickness of 0.12 mm until a layer with a thickness of 0.18 mm is formed.

The dried layers on the plates (after cutting and impregnating the edges) are used in the CHROMPRES 10 ultramic chamber to divide the inverted alkaloids in the directions of acetonitrile and 0.005 M solution of K 2 PO 4 in a ratio of 6: 4. Dragendorff reagents containing ethyl acetate.

Example 11

Using the binder described in Example 9, the following preparative layer is applied:

g of silica gel having an average particle size of 5a and an inner pore diameter of 60. 10 ¹⁰ m was mixed with 135 ml of binder, which was diluted with 175 ml of water during 85 seconds on a Waring blender to form product slurry.

The slurry obtained is applied to a grease-free aluminum foil 0.11 m thick by coating until a layer of 0.65 mm thick is formed. This layer has a thickness of 0.5 mm after drying.

This silica gel layer is used for the preparative preparation of -methylated lysine resulting from the spontaneous methylation and formylation reaction occurring between L-lysine and formaldehyde. Water is used as eluent. The cushion pressure was 1.3 MPa.

OBJECT OF THE INVENTION

A process for the production of a polyacrylamide binder for fixing fine-grained sorption layers

Claims (4)

Method for producing a polyacrylamide binder for fixing fine-grained sorbent layers with a particle size range of 2 to 20 µm and in particular with a narrow particle size range in the range of Δ / im <2 based on organic and / or inorganic substances and / or optionally bound apolar phase for Pressurized single layer and multilayer chromatography, characterized in that a polyacrylamide gel base formed from a mixture of a volume / volume concentration of 1.6 to 2.5 »aqueous acrylamide solution and 0.6 to 1.0» aqueous N, N * solution is formed from a polyacrylamide gel base. -methylene-bis-acrylamide by the action of catalysts such as Ν, Ν, Ν ', Ν'-tetramethylethylenediamine and ampniumperoxydisulfate at a temperature between 21 and 30 ° C after homogenization with a water-soluble solvent precipitates a fraction suitable as a binder with acetone, methanol or ethanol the precipitate obtained is then liquefied by the action of water, and then the precipitation and liquefaction process is repeated at least once. 2. Process according to claim 1, characterized in that the acrylamide and N, N-methylene-bis-acrylamide are used in an aqueous solution in a concentration by volume of between 1.9 and 2.2% and 0.8 and 1.0, respectively. %. 3. The process of claim 1 wherein the catalyst is ammonium peroxydisulfate and 3-dimethylaminopropionitrile. 4. The process of claim 1 wherein the polymerization reaction is started at 22 ° C.