Method of preparation of high-efficient columns with polymer sorbents for liquid chromatography

FIELD: liquid chromatography.

SUBSTANCE: to prepare high-efficient columns with polymer absorbents the suspension of absorbent is prepared in water solution of alkali having pH=11-14 with exposure time of 0,5-60 hours. Absorbent is packed in sealed in column in alkali water solution as well.

EFFECT: improved efficiency of exploitation.

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The invention relates to liquid chromatography and can be used to obtain efficient columns for the separation of biopolymers, for the Express control of the molecular mass distribution (MMD) of oligomers of ethoxysilanes in the hydrolyzed and non-hydrolyzed ethylsilicate, as well as for other cases of chromatographic processes.

For the preparation of modern high-performance columns are widely used polymeric sorbents on the basis of polystyrene (PS) and polystyrene-divinylbenzene (PS-DVB) with a high degree of crosslinking, and the existing technologies allow to obtain a fine fraction monotermicheskih grains with a diameter of 3-10 μm [1, 2].

Polymeric sorbents used in high performance liquid chromatography (HPLC), must have certain properties on the parameters values: mechanical strength, volume change in organic and aqueous-organic media, pore size, pore size, specific surface area and hydrophobicity.

In most cases, of the above characteristics that define the applicability of polymeric sorbent in HPLC, the main ones are its mechanical strength and the degree of swelling in organic and aqueous-organic media.

Synthesized according to the patent [2] monofonicheskie granules of polymer sorbent based on PS-DVB Packed in a chromatographic column, change the amount of swelling in dichloromethane (good solvent) 9-20%and 50% solution of methanol in water (poor solvent) 0.03 to 0.15%.

The chromatographic column, Packed monofonicheskie granules with a diameter of 3 μm polymeric sorbent based on PS-DVB, have an efficiency of more than 50,000 theoretical plates/meter (TT/m) [2]. But in the patent [2] does not specify the type of solvent used for preparing the suspension of the sorbent and the conditions of preparation technique of columns.

It should be noted the number of properties that fundamentally distinguish sorbents on the basis of supersewn polystyrene (JCSS) from all known polymeric sorbents. Dry JCSS swells in any solvent, regardless of the solubility parameter [3, 4]. Starting with 20% degree of crosslinking, the polymers of this type exhibit the ability to swell in methanol, ethanol and hexane.

Currently, the Purolite company, UK, produces a number of JCSS sorbents, both hydrophobic and contains katiana - and anion-exchange groups, under the General title Macronet (MN). Their characteristics are presented in [5]. These sorbents are used to extract organic compounds from water in industrial scale. From grains of unmodified hydrophobic sorbent MN-200, you can get small particles suitable for HPLC, with the diameter of the macropores 850-950 Å and micropores 15 Åthe work is the following at pH 0-14.

Among JCSS for HPLC, the most studied chemical structure of the MN-200 [6], which is studied in [7]. JCSS MN-200 compared to sorbent based on PS-DVB is less swelling in tetrahydrofuran 3.9 times and acetonitrile 8.7-12 time [6, p.6].

One of the unique properties of unmodified JCSS is that, despite the high hydrophobicity of the sorbent, its surface is wetted. Studies have shown that the surface JCSS MN-200 has a charge, and the magnitude and sign of the charge is determined by the pH of the solution containing the sorbent [7]. In accordance with the dependence of Zeta-potential (ξ) on pH, at pH<4,3 unmodified JCSS MN-200 has a positive charge, reaching a maximum value at pH 2.5 and 2.7, and at pH>the 4.3 has a negative charge, reaching a maximum value at pH 8-9.

According to elemental analysis, along with carbon and hydrogen MN-200 contains a small amount of chlorine and about 6% oxygen. Thus, the presence of positive charge on the surface of unmodified JCSS can only be explained by the presence of oxygen atoms in the structure of the polymer matrix. The nature of functional groups on the surface of the MN-200 was studied by solid state NMR13With, x-ray photoelectron spectroscopy and infrared spectroscopy with Fourier transformations is the Finance [7, 8]. Installed on the surface of the JCSS are ketone, ether (R-O-R) and the functional alcohol groups, the exact concentration of each of which cannot be determined.

Potentiometric titration MN-200 showed that on its surface in addition to the carbonyl are cation-exchange group of the three types: weak and strong acid, and phenol [6, 87].

In [6, p.53] fill in the columns JCSS MN-200 was carried out in the form of a suspension in acetone, but other conditions methodology fill all the columns not shown.

In [9, s.89] fill in the columns neutral JCSS brand Chromalite 5 HGN carried out in suspension, but what used solvents and conditions of the methodology fill all the columns not shown.

The sorbents type μ-storages (a copolymer of styrene and divinylbenzene) with a small pore size (100 Å 500 Å) observed shrinkage of the layer of sorbent in the column both in polar and nonpolar solvents. Convenient, albeit expensive solution is to use separate sets of columns for each of the employed solvent. Some companies with this purpose produce columns with the same pore size, filled with different solvents - tetrahydrofuran, toluene, chloroform and dimethylformamide [10].

Columns for HPLC with polymeric sorbents on the basis of a copolymer of styrene and is of vinylbenzene with a diameter of 10 μm and a pore diameter of 500 Å , 1000 Å have the following efficiency (thousand TT/m): μ-styragel filled in toluene - 10; μ-spherogel filled in toluene - 18; ultrastyragel filled in toluene - 46; ultrastyragel filled in tetrahydrofuran - 40; TSK - gel filled in tetrahydrofuran - 20 [10].

As you can see, the columns for HPLC with polymeric sorbents on the basis of a copolymer of styrene and divinylbenzene have different efficiency, which largely depends on the method of filling the columns.

Given that supersewn polymeric sorbents on the basis of polystyrene, polydivinylbenzene and polystyrene-divinylbenzene not swell in water, it would seem that the water - ideal eluent for packing columns. However, in water eluent these sorbents do not form a suspension and does not disintegrate agglomerates of grains sorbents, which prevents tight packing of the sorbent columns for HPLC.

The closest in technical essence and the achieved result for the proposed method, is selected as the closest analogue is the way of cooking columns for HPLC suspension method comprising: weighting required for speakers of this size, amount of sorbent, fill it with solvent and preparation of the suspension. The suspension is placed in a reservoir connected with the column, at the end of which is mounted a fitting with a filter, and the pressure of 20-60 MPa push the suspension through the column, feeding in tank pump solvent. The suspension is filtered in the filter column, forming an ordered layer of sorbent that provides efficient separation with HPLC. Stop the flow of solvent, allow the pressure to drop to zero and remove the column. Remove excess sorbent with the bottom of the column and attach the second fitting with the filter. Thus obtained column set to the chromatograph, pumped through it to equilibrium work the solvent, after which it is ready to work [10, p.151].

The solvent for preparing the suspension of the sorbent is often the determining factor for the quality of the packing of the column, as the suspension should remain stable, ranging from transferring it to the tank and during the whole package, or you need to slow sedimentation or to exclude it. Solvents with sorbents can give a true suspension deposited in accordance with Stokes ' law (in which particles are distributed in the form of individual particles), and "glued" to the suspension deposited much faster and containing lumps of several particles of the sorbent [10, str-153].

True suspension are deposited in the form of dense, trudnoispolnimaya sediment. "Glued" to the suspension are deposited in the form of friable and legalisierung sediment. Preference should be given to solvents, giving deposited sorbent true suspension.

Opinions about the concentration of the suspension, the optimal packing of columns diverge: some authors get the best results with very dilute suspensions (1-5%), concentration (10-30%). Obviously, for each system solvent-sorbent there is a range of concentrations of the suspension, giving the best packaging layer of sorbent [10, p.153].

However, this method of preparation of high-performance speakers with supersewn polymeric sorbents on the basis of polystyrene, polystyrene-divinylbenzene and polydivinylbenzene in suspension in the oxygen-containing polar organic solvents (e.g. acetone or alcohols) has the following disadvantages:

1. Unable to obtain a uniform and dense layer structure of the sorbent in the column due to the presence on the surface of the JCSS positive or negative electric charges. The negative charge on the surface of the JCSS is due to the presence of carboxyl, strong acid, weak acid and functional phenolic groups, and the presence of positive - presence of metal cations in the structure of this polymer, such as the chlorides of iron, tin, titanium, aluminum, which are used as catalysts for the reaction of the Friedel-crafts reaction of the crosslinking chains of linear polystyrene methylene groups, and hydrolyzed in water dissolve the Ah.

2. Unable to obtain a uniform and dense layer structure of the sorbent in the column due to the presence on the surface of PS-DVB and polydivinylbenzene sorbents positive charge. The presence of a positive charge associated with the presence of metal cations in the structure of these polymers, such as the chlorides of iron, tin, titanium, aluminum, zinc, etc. that are used as catalysts for reactions Friedel-and hydrolyzed in aqueous solutions.

3. The presence of carbonyl, carboxyl and other groups on the surface supersewn polymer sorbents, as well as content in the polymer structure, cations of iron, tin, titanium, aluminum, zinc leads to sorption of organic substances of biomolecules in blood plasma, Monomeric silicic acid and its oligomers in the chromatographic separation.

4. The presence of carbonyl and carboxyl groups on the surface supersewn polymeric sorbent-based polydivinylbenzene leads to swelling of the sorbent in the column within 30-35 days in the mobile phase is dehydrated ethanol, which leads to a sharp increase in pressure at the inlet into the column.

5. Due to the different degree of swelling supersewn polymer sorbents in organic and aqueous-organic media, in the process of separation columns when using eluents containing 50-95% water, are formed of microposts the column, reducing separation efficiency.

6. Change the positive charge on the surface supersewn polymer sorbents in water at pH higher than 2.5 is related to the gradual hydrolysis of cations of iron, tin, titanium, aluminum, zinc, resulting in the formation of microplate in the column, which leads to sagging of the sorbent in the column and, accordingly, decrease in the efficiency of separation.

The problem solved by this invention is the elimination of the swelling sorbents in the cooking process columns, loss prevention effectiveness of columns in the process of exploitation by the removal of cations of metals, carbonyl and carboxyl groups from the surface supersewn polymer sorbents on the basis of polystyrene, polystyrene-divinylbenzene and polydivinylbenzene and destruction of agglomerates monotermicheskih grains sorbent.

The solution of this problem is provided by the fact that the proposed method of preparation of high-performance speakers with polymeric sorbents for liquid chromatography includes the preparation of suspension monotermicheskih grains supersewn polymeric sorbent on the basis of polystyrene, polystyrene-divinylbenzene and polydivinylbenzene diameter of 5 and 10 μm in an aqueous alkali solution with a pH 11-14, keeping it at room temperature for 0.5-60 hours to remove from the surface the displacement of the sorbent of metal cations, carbonyl and carboxyl groups; introducing the slurry into the column, the packing of the sorbent in the column and seal at maximum pressure (250 to 300 ATM.) serial transmission aqueous alkali solution with a pH of 11 to 14, in which there is swelling of the sorbent at room temperature.

Prepared chromatographic column (150 mm × 3 mm), filled monofonicheskie grains supersewn polymeric sorbent on the basis of polystyrene, polystyrene-divinylbenzene and polydivinylbenzene diameter of 5 and 10 μm have the efficiency 30000-40000 TT/m in hexane (at a rate of eluent - 96%ethanol and 0.1 ml/min).

Highly effective exclusion-chromatography columns are characterized by the following parameters: monofonicheskie grain sorbent have a diameter of 10 microns or less [11, p.1, 113]; the length of the column when the particle size of the sorbent 5-6 μm is 10-15 cm [11, s]; column diameter of 0.26 to 0.70 cm [11, .183]; column backpressure up to 7000 psi (490 at) [11, s, 141]; the flow rate of eluent to 3 ml/min [11, s]; volume flow cell Refractometer 5-10 ál of [11, s]; column the sorbent particles 10 microns gives the efficiency 7000-10000 TT 25 cm length.

Example 1. 1.5 cm3monotermicheskih grains with a diameter of 10 μm supersewn polystyrene sorbent (JCSS) brand Chromalite 10HMN2 with a pore diameter of 1000 Åplaced in 10 cm396%ethanol at the room for the Noah temperature. After 1 hour the suspension JCSS transferred to a glass filter with a pore diameter of less than 10 μm in ethanol and filtered under vacuum. JCSS is transferred onto a sieve with a mesh size of 20 μm and wipe it through a sieve with a fractional addition of (0.5-1.0 cm3) 15 cm396%ethanol for destruction of agglomerates monotermicheskih grains sorbent. Suspension JCSS put in a metal device for filling columns with a volume of 15 cm3, seal it with the head, which attaches to the metal housing by means of a fitting and PTFE gaskets glass column length of 150 mm, an inner diameter of 3 mm (150 mm × 3 mm), at the opposite end of which is mounted a metal filter, PTFE gasket and fitting. Device for filling columns with attached column overturn, and filling the column JCSS is carried out in the position from the bottom-up. With a continuous increase of pressure up to 30 MPa displacement suspension JCSS through the column, giving the device to fill speakers pump solvent. Suspension JCSS is filtered in the filter column, forming poradochnij layer of sorbent. When pumping through a column of 15 cm3ethanol, stop the flow of solvent, the pressure is reduced to zero and disconnect the column. Remove excess sorbent with the bottom of the column using a scalpel, the moustache is enableval metal filter, PTFE gasket and attach the second fitting. Filled JCSS column mounted on a liquid chromatograph, pumped through it to equilibrium work the solvent, after which it is ready for use. Prepared by such actions by a known method [10] it has been successful in hexane 4000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min). In future work when using the eluent is water with a pH 1-13 happens subsidence layer JCSS in the column and, consequently, reduce the efficiency of the column. This is due to the fact that the agglomerates monotermicheskih grains JCSS not completely destroyed when wiping it through a sieve, and when using the eluent is water with a pH 1-13 there is a change in charge monotermicheskih grains JCSS and hydrolysis of the chlorides of metals (iron, tin, titanium, aluminum, zinc and others).

When chromatographic separation on a column with JCSS oligomers of ethoxysilanes and silicic acid present in the hydrolyzate of tetraethoxysilane, (eluent absolute ethanol and 0.1 ml/min), there sorption of silicic acid on the sorbent.

The use of organic solvent is ethanol for the preparation of suspensions monotermicheskih grains sorbent JCSS when filling the column at high pressure (30 MPa) by a known method [10] cannot provide speakers with high the efficiency for HPLC.

Example 2. A glass column (150 mm × 3 mm) with monofonicheskie grains JCSS diameter of 10 μm brand Chromalite 10HMN2 with a pore diameter of 1000 Å prepared analogously to example 1, with the difference that for the preparation of suspensions monotermicheskih grains JCSS use toluene as in the known method [10]. Cooked column has been successful in hexane 1500 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min). In future work when using the eluent is water with a pH 1-13 happens subsidence layer JCSS in the column.

The use of organic solvent as in the known method [10] - toluene to prepare a suspension monotermicheskih grains sorbent JCSS when filled column at high pressure (30 MPa) by a known method [10] cannot provide speakers with high efficiency for HPLC.

Example 3. A glass column (150 mm × 3 mm) are prepared analogously to example 1 by a known method [10], with the difference that for the preparation of columns use monofonicheskie grain diameter of 10 μm longevity highly crosslinked polydivinylbenzene sorbent with a pore diameter of 500 Åthat can withstand pressures up to 30 MPa. Fill the column with the suspension of the sorbent is carried out at a pressure of 25 MPa.

Cooked column has been successful in hexane 3500 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min). Later work using eluent - water with a pH 1-13 happens subsidence layer of the sorbent in the column. This is due to the fact that the agglomerates monotermicheskih grains polydivinylbenzene sorbent is not completely destroyed when wiping sorbent through a sieve, and when using the eluent is water with a pH 1-13 there is a change in charge monotermicheskih grains sorbent.

The use of organic solvent, as in the known method [10] - ethanol for the preparation of suspensions monotermicheskih grains longevity highly crosslinked polydivinylbenzene sorbent when filling the column at high pressure (25 MPa) cannot provide speakers with high efficiency for HPLC.

Example 4. A glass column (150 mm × 3 mm) with monofonicheskie grains polymeric sorbent based on polystyrene-divinylbenzene (PS-DVB) with a diameter of 10 μm and a pore diameter of 500 Å prepared analogously to example 1, with the difference that for the preparation of suspensions monotermicheskih grains PS-DVB sorbent using tetrahydrofuran as in the known method [10]. Cooked column has been successful in hexane 4500 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min). In future work when using the eluent is water with a pH 1-13 happens subsidence layer of PS-DVB sorbent in the column.

The use of organic solvent is tetrahydrofuran (THF) to prepare a suspension of monof the historical grain of PS-DVB sorbent when filled column at high pressure (30 MPa) by a known method [10] cannot provide speakers with high efficiency for HPLC.

Example 5. Preparing a suspension of 1.5 cm3monotermicheskih grains JCSS diameter of 10 μm brand Chromalite 10HMN2 with a pore diameter of 1000 Åin accordance with the proposed invention, is placed in a 10 cm3an aqueous solution of alkali (NaOH) to pH 13, and leave at room temperature for 12 hours. Then the suspension JCSS put in a metal device for filling columns with a volume of 15 cm3, seal it with the head. The head attaches to the metal housing by means of a fitting and PTFE gaskets glass column (150 mm × 3 mm), at the end of which is mounted a metal filter, PTFE gasket and fitting. Device for filling columns with attached column overturn, and filling the column suspension JCSS is carried out in the position from the bottom-up. With a continuous increase of pressure up to 30 MPa displacement suspension JCSS through the column, giving the device to fill speakers pump aqueous solution of alkali with a pH of 13. Suspension JCSS is filtered in the filter column, forming poradochnij layer of sorbent. After pumping through the column 15 cm3an aqueous solution of alkali, stop the flow of solvent, the pressure is reduced to zero and disconnect the column. Remove excess sorbent with the bottom of the column using a scalpel, install metal filter, fluoropolymers is th strip and attach the second fitting. Filled JCSS column mounted on a liquid chromatograph, pumped through it distrurbance water to remove the alkali, and then 96%ethanol until equilibrium is reached, after which it is ready for use. Cooked column has been successful in hexane 30000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min).

When using the eluent is water with a pH 1-13 does not occur subsidence layer JCSS brand Chromalite 10HMN2 in the column. This is due to the fact that the agglomerates monotermicheskih grains JCSS when filling the column dissolved in an aqueous alkali solution, as it removes carbonyl and carboxyl groups on the surface of the sorbent and metal chlorides.

Figure 1 shows the chromatogram of oligomers of ethoxysilanes in the hydrolyzate of tetraethoxysilane obtained in column (300 mm × 3 mm) (United two glass columns 150 mm × 3 mm) with JCSS brand Chromalite 10HMN2. Oligomers of ethoxysilanes: 1 - oligoadenylates (Si13), 2-4 - preparation (Si2-Si6) and monomers: 5 - tetraethoxysilane, 6 - silicic acid. The detector is a differential Refractometer RIDK-102 easily adjusted by cyclohexane, sensitivity 16×10-7units of refraction; speed dry eluent - 0.2 ml/min of toluene containing 1% isopropanol; temperature thermostat column, injector and detector - 25°; dosing volume pet is and - 10 μl; sample 10 ál of 0.1% hydrolyzed tetraethoxysilane in dry toluene containing 1% isopropanol.

When chromatographic separation on a column with JCSS brand Chromalite 10HMN2 not observed sorption of silicic acid contained in the hydrolyzate of tetraethoxysilane.

Example 6. A glass column (150 mm × 3 mm) with monofonicheskie grains JCSS diameter of 10 μm brand Chromalite 10HMN2 with a pore diameter of 1000 Å prepared according to the invention, analogously to example 5, with the difference that for the preparation of suspensions monotermicheskih grains sorbent using an aqueous solution of alkali (NaOH) to pH 14, and the processing time of the sorbent in alkali is 30 minutes. Cooked column has been successful in hexane 30000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min).

When using the eluent is water with a pH 1-14 happens subsidence layer JCSS brand Chromalite 10HMN2 in the column. This is due to the fact that the agglomerates monotermicheskih grains JCSS when filling the column dissolved in an aqueous alkali solution, as it removes carbonyl and carboxyl groups on the surface of the sorbent, and chlorides of the metals as a result of hydrolysis.

Example 7. A glass column (150 mm × 3 mm) with monofonicheskie grains JCSS diameter of 10 μm brand Chromalite 10HMN2 with a pore diameter of 1000 Å prepared analogously to example 5, with the difference that you need a kitchen is ing suspension monotermicheskih grains sorbent using an aqueous solution of alkali (NaOH) at pH 11, and the processing time of the sorbent in alkali is 60 hours. Cooked column has been successful in hexane 30000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min).

When using the eluent is water with a pH 1-13 does not occur subsidence layer JCSS brand Chromalite 10HMN2 in the column. This is due to the fact that the agglomerates monotermicheskih grains JCSS when filling the column dissolved in an aqueous alkali solution, as it removes carbonyl and carboxyl groups on the surface of the sorbent, and chlorides of the metals as a result of hydrolysis.

Example 8. A glass column (150 mm × 3 mm) prepared according to the invention, analogously to example 5, with the difference that for the preparation of columns use monofonicheskie grain diameter of 10 μm longevity highly crosslinked polydivinylbenzene sorbent with a pore diameter of 500 Å and filling the column with the suspension of the sorbent is carried out at a pressure of 25 MPa. Cooked column has been successful in hexane 30000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min).

When using the eluent is water with a pH 1-13 does not occur subsidence layer polydivinylbenzene sorbent in the column. This is due to the fact that the agglomerates monotermicheskih grains sorbent when filling the column dissolved in an aqueous alkali solution, as it removes carbonyl and carboxyl groups from the surface of the absorbents is A.

Figure 2-3 shows the chromatogram obtained on a column with polydivinylbenzene sorbent with a diameter of 10 μm. Detector signals through the interface to record into the computer using the program "Achrom".

Figure 2 presents the chromatogram of the definition of the fluorescent complexes of glutathione and metallothionein with N-(9-acridine)-maleimide (NAM) in the combined acetonitrile extracts of blood plasma (10 µl) of cattle (cows) from Tyrnaus. 1, 2, 3, 6, 7, 8 - metallothionein with NAM with retention times 2,14, 2,31, 2,56, 5,22, 6,06, 8,02 min; 4, 5 - metallothionein + glutathione with NAM retention times of 3.32, 4,14 minutes

When determining metallothionein in the blood plasma of animals used method [12] with the following modifications:

- from the blood plasma of metallothionein were extracted with acetonitrile, with high molecular weight proteins were visados;

after centrifugation the combined acetonitrile extracts from plasma subjected derivatization and conducting the reaction with NAM by the method of [12];

Detector - fluorescent RF-530 (Shimadzu), excitation at 360 nm, fluorescence at 435 nm; speed eluent - 0.4 ml/min 0.05 M phosphate buffer pH 6.5, containing 35% ethanol; sample 10 ál of derivatization of the combined acetonitrile extracts of blood plasma in 0.05 M phosphate buffer with a pH of 6.5.

The chromatography was carried out combined acetonitrile extracts metallothionein inplasma blood of animals, can significantly improve the sensitivity analysis by increasing the volume of the investigated plasma and to reduce the analysis time to 25 min by reducing coextraction substances, reagiruesh with NAM.

Figure 3 presents the chromatogram of the standard definition of metallothionein (100 ng) in the form fluorescent complexes with NAM by the method of [12]. 1-9 - metallothionein with NAM with retention times 2,12, 2,31, 3,40, 4,33, 6,08, 6,47, 11,45, 14,45 and 15,58 minutes

Detector - fluorescent RF-530 (Shimadzu), excitation at 360 nm, fluorescence at 435 nm; speed eluent - 0.4 ml/min 0.05 M phosphate buffer pH 6.5, containing 35% ethanol.

Example 9. A glass column (150 mm × 3 mm) prepared according to the invention, analogously to example 5, with the difference that for the preparation of columns use monofonicheskie grain diameter of 5 μm longevity highly crosslinked polydivinylbenzene with a pore diameter of 500 Å and filling the column with the suspension of the sorbent is carried out at a pressure of 25 MPa. Cooked column has been successful in hexane 40000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min).

When using the eluent is water with a pH 1-13 does not occur subsidence layer polydivinylbenzene sorbent in the column due to the fact that the agglomerates monotermicheskih grains sorbent when filling the column dissolved in an aqueous alkali solution, as it removes carbonyl and carboxyl groups on the surface of the sorbent.

4 shows the chromatogram obtained on a column with polydivinylbenzene sorbent diameter of 5 μm, oligom the ditch of ethoxysilanes in the hydrolyzate of tetraethoxysilane. Oligomers of ethoxysilanes: 1 - oligoadenylates (Si13), 2-4 - preparation (Si2-Si6) and monomers: 5 - tetraethoxysilane and 6 - silicic acid (Si(OH)4). The detector is a differential Refractometer RIDK-102 easily adjusted in absolute ethanol sensitivity 8×10-7units of refraction, the speed of elution solvent is absolute ethanol to 0.18 ml/min; temperature thermostat column, injector and detector - 25°; dosing volume loops - 10 ál; sample 10 ál of 0.4% of the hydrolyzate of tetraethoxysilane in absolute ethanol.

When chromatographic separation on a column with polydivinylbenzene sorbent is not observed sorption of silicic acid on the sorbent contained in the hydrolyzate of tetraethoxysilane.

Figure 5 presents the chromatogram obtained on a column with polydivinylbenzene sorbent diameter of 5 μm, hydrated forms of sodium sulfate - 1-8 with retention times 3,16, 3,32, 4,08, 4,26, 5,09, 6,33, 7,43, 8,46 min Detector UV 230 nm (spectrophotometer Hitachi 320 cuvette with a volume of 7 μl); the rate of eluent - 0.2 ml/min 80% acetonitrile in water; sample 10 µl of a saturated aqueous solution of sodium sulfate.

Example 10. A glass column (150 mm × 3 mm) with monofonicheskie grains longevity highly crosslinked polydivinylbenzene sorbent diameter of 5 μm with a pore diameter of 500 Å prepared for the proposed izobreteny is similar to example 9, with the difference that for the preparation of the suspension of the sorbent using an aqueous solution of alkali (NaOH) to pH 11, and the processing time of the sorbent in alkali is 60 hours. Cooked column has been successful in hexane 40000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min).

When using the eluent is water with a pH 1-13 does not occur subsidence layer polydivinylbenzene sorbent in the column due to the fact that the agglomerates monotermicheskih grains sorbent when filling the column dissolved in an aqueous alkali solution, as it removes carbonyl and carboxyl groups on the surface of the sorbent.

Example 11. According to the invention, a glass column (150 mm × 3 mm) with monofonicheskie grains polymeric sorbent based on polystyrene-divinylbenzene with a diameter of 10 μm with a pore diameter of 500 Å prepared analogously to example 5. Cooked column has been successful in hexane 35000 TT/m (at a rate of eluent - 96%ethanol and 0.1 ml/min).

When using the eluent is water with a pH 1-14 happens subsidence layer of PS-DVB sorbent in the column. This is due to the fact that the agglomerates monotermicheskih grains PS-DVB sorbent when filling the column dissolved in an aqueous alkali solution, as it removes carbonyl and carboxyl groups on the surface of the sorbent and metal chlorides as a result of hydrolysis.

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11. W.W.Yau,J.J.Kirkland, D.D.Bly. Modern Size-Exclusion liquid chromatograhy. Practice of Gel permleation and Gel Filtration Chromatograhy. New York-Chichester-Brisban-Toronto, 1979. P.393.

12. Kamata K. Sensitive Fluorometuy of metallothionein as a functionl metal carrier in body // Japan-Russia International Symposium on Environmental Studies. Tohoku Fukushi University: Sendai, 2003, p.9-10.

1. Method of preparation of high-performance speakers with polymeric sorbents for liquid chromatography, comprising preparing a suspension monotermicheskih grains supersewn polymeric sorbent on the basis of polystyrene, polystyrene-divinylbenzene and polydivinylbenzene in solution, the introduction of the slurry into the column, the bursting of the suspension through the column at elevated pressure when applying the solution, packing, sealing and forming poradocnogo layer of sorbent, pumping the solution through the column and the lower pressure, characterized in that as a solution using an aqueous alkali solution with a pH of 11 to 14, and before the introduction of the suspension into the column sorbent stand in the above-mentioned solution for 0.5-60 hours.

2. The method according to claim 1, characterized in that for the preparation of suspensions use grain sorbent diameter of 5 and 10 microns.

3. The method according to claim 1, characterized in that the seal of the sorbent is carried out at a maximum pressure of 25-30 MPa.



 

Same patents:

FIELD: liquid chromatography.

SUBSTANCE: to prepare high-efficient columns with polymer absorbents the suspension of absorbent is prepared in water solution of alkali having pH=11-14 with exposure time of 0,5-60 hours. Absorbent is packed in sealed in column in alkali water solution as well.

EFFECT: improved efficiency of exploitation.

3 cl, 5 dwg, 11 ex

FIELD: chemical technology.

SUBSTANCE: invention relates to a method for synthesis of ester perfluorinated derivative by using a chemical reaction. This reaction represents the fluorination reaction of the parent compound as a raw, the reaction of chemical conversion of fragment of ester perfluorinated derivative to yield another ester perfluorinated derivative or the interaction reaction of carboxylic acid with alcohol under condition that at least one or reagent, i. e. carboxylic acid or alcohol, represents a perfluorinated compound wherein indicated perfluorinated derivative of ester represents a compound comprising a fragment of the formula (1):

with a boiling point 400°C, not above. The reaction time for carrying out abovementioned chemical reaction is sufficient to provide the required yield of ester perfluorinated derivative and wherein this yield of ester perfluorinated compound is determined by the gas chromatography method by using a nonpolar column. Also, invention relates to a method for pyrolysis of ester perfluorinated derivative with a boiling point 400°C, not above, to yield the dissociation product wherein this product represents a derivative of acyl fluoride or ketone and wherein pyrolysis time is sufficient to provide the required degree of conversion of ester perfluorinated derivative and wherein the indicated conversion degree of ester perfluorinated derivative is determined by gas chromatography method by using a nonpolar column. Also, invention relates to a method for analysis of ester perfluorinated derivative with a boiling point 400°C, not above, that involves analysis of ester perfluorinated derivative in a sample containing ester perfluorinated derivative by gas chromatography method by using a nonpolar column wherein ester perfluorinated derivative represents compound comprising a fragment of above given formula (1).

EFFECT: improved method of synthesis.

8 cl, 1 dwg, 2 ex

FIELD: chemistry.

SUBSTANCE: in the open chromatographic capillary column consisting of capillary on internal surface of which evenly longwise of column the bed of keeping substance is put which is executed in the form of an indissoluble film with a regular cellular structure with effective diameter over the range 2-30 nanometers, and the deviation from effective diameter is subordinated to the law of Gauss with a dispersion no more than 5 nanometers. Thus keeping substance consists of oxides on the basis of silicon, aluminium, the titan, or siloxane copolymer, contains either carbon, or polymer on the basis of divinyl benzene, copolymers of divinyl benzene and styrene, vinylpyridine and divinyl benzene, styrene and, ethylene glycol dimethacrylate, and a capillary material on which the structured bed is put, is the quartz, glass, metal.

EFFECT: achievement of specific efficiency to the value of 2100-2500 theor plates on metre and possibilities to work at the raised values of a gas stream of the carrying agent without an essential decline of efficiency; separation process acceleration without a significant decline of dividing properties of a column; time decreasing of the analysis at a problem solving.

6 cl, 2 ex, 4 dwg

FIELD: technological processes.

SUBSTANCE: in the method, portions of adsorbent, which is dispersed in disperse medium, then periodically metered in capillary column with further removal of this dispersed medium with inertial gas, moreover, portions of dispersed adsorbent are metered in the form of adsorbent aerosol, which is produced in the result of bubbling contact of inertial gas with adsorbent sol that contains volatile substance. Device for method implementation consists of sequentially connected balloon with inertial gas, unit of gas preparation, thermostatically controlled tank with adsorbent sol, switching tap and thermostatically controlled capillary column, and is additionally equipped with bubbler with controlled pneumatic resistance at the outlet.

EFFECT: improves efficiency and separating ability of capillary gas adsorbing column.

2 cl, 1 dwg

FIELD: physics, measurements.

SUBSTANCE: proposed method can be used in chemical, petrochemical, medical and other industries for gas-chromatography proximate analysis of compound mixes of natural technogenic origin substances. The sorbent layer is dynamically formed on the capillary column inner surface by periodical metered feed of aerosol portion into inert gas flow that blows through the column, the said aerosol portion being produced by bubbling inert gas through solid carrier suspension and subsequent removal of the solvent from the column by inert gas. The proposed device comprises a bubbler with solid carrier suspension in the liquid phase solution, its inlet being submerged into suspension while its outlet line being communicated with gas space above the suspension. Note that, additionally, the proposed device comprises a flows divider furnished with a solid particle entrapping vessel communicating with the discharge line via adjustable fluidic resistor.

EFFECT: higher efficiency of proposed method.

2 cl, 1 dwg

FIELD: physics.

SUBSTANCE: column packing method uses an automatic control unit which has software and hardware for automatic operation. The method also involve use of a column which has a movable adapter. The movable adapter can move by pumping liquid into or from the sealed space between the adapter and the cover of the column. The method also involves use the control unit to track movement of the movable adapter in the column. The control unit is programmed to fill the column with working material of a sorbent layer in accordance with current parametres of the working material. Current parametres pertain to given height of the packing layer, volume of suspension with given particle concentration, rate of descent of the adapter and the required degree of compression of the sorbent. The disclosed method also uses the control unit to determine the control point where the movable adapter starts compressing the said deposited layer by calculating the position where pressure starts to increase in the said sealed space.

EFFECT: design of a column packing system and a method of packing working material in which a sorbent layer with an optimum compression index is obtained, as well as possibility of reproducible and controlled filling of chromatographic columns.

8 cl, 2 dwg

FIELD: process engineering.

SUBSTANCE: this invention relates to column packing system and methods of packing, particularly, to packing chromatographic columns. Proposed method comprises defining concentration of chromatographic suspension, volume of column at chromatographic column, and defining chromatographic medium compression ratio. Besides, method comprises calculating suspension volume proceeding from defined column volume, defined compression ratio and defined suspension concentration. Note here that said packed suspension volume allows chromatographic medium packing layer with definite compression ratio over entire column volume. Also, the method comprises placing designed suspension volume in suspension tank, mounting chromatographic column to feed designed suspension volume, packing chromatographic column and tracking designed volume of suspension into chromatographic column. Method comprises automatic shut-off of suspension feed into chromatographic column when suspension volume equals designed suspension volume.

EFFECT: higher accuracy and reproducibility.

3 cl, 6 dwg

FIELD: chemistry.

SUBSTANCE: in method portions of solid carrier, dispersed in volatile dispersion medium, are periodically sprayed on the surface of silicon plate with preliminarily etched channels for microchromatographic column in form of aerosol in inert gas, with the following sealing by anode bonding of silicon plate with Pyrax brand glass. After that, immobile liquid phase in form of aerosol in inert gas is applied on the surface of solid carrier. Device for method realisation contains successively connected balloon with inert gas, unit for gas preparation, two thermostatically controlled tanks with solution of immobile liquid phase and solid carrier suspension, pulveriser, switching tap and special bubbler with regulated pneumoresistor at the output.

EFFECT: increased efficiency and separating ability of gas-liquid-solid-phase microchromatographic columns on silicon plates.

2 cl, 2 dwg, 1 tbl

FIELD: chemistry.

SUBSTANCE: channels for microchromatographic column are obtained on the surface of flat plate with their further sealing and filling with respective sorbent, with channels for microchromatographic column on flat plate being obtained by method of laser ablation, and flat plates being made of various metals, silicon, glass or polymers. In addition, sealing of microchromatographic column is carried out with glass plate through polymer film gasket under vacuum and impact of temperature.

EFFECT: extension of assortment of materials for manufacturing microchromatographic columns with application of laser ablation.

2 cl, 1 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: multipurpose planar micro-chromatograph containing exchangeable, independently controlled analytical modules for determining the composition of the organic and inorganic components of the studied complex mixtures. Each analytical module includes a thermostatic planar micro-chromatographic column with the thermostatic planar microdoser at inlet and the micro-detectors of thermal and thermochemical conductivity at output.

EFFECT: improving reliability in operation and miniaturization of the chromatographic columns, reducing the preparation time of the chromatograph for the next analysis and increasing sensitivity in the analysis of the organic sample components.

3 cl 4 dw

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