The multistage improvement column that is used for biological specimen polychlorinated biphenyl quick pretreatment and purifying
Technical field
The present invention relates to the chromatographic technique field, be specifically related to a kind of improvement post of forming by novel column packing, can be used for the quick pretreatment and the purifying of polychlorinated biphenyl in the complex biological sample.
Background technology
The polychlorinated biphenyl organic contaminant is one of common environmental contaminants.They are synthetic by chemical industry usually, discharge or enter in the different surrounding mediums by different approaches, and this compounds be the hydrophobicity oleophilic substance mostly, thereby can enrichments in a large number in biosome fat.Nineteen sixty-eight, Japan once took place to pollute the famous nuisance disease that rice bran oil causes because of PCB.Though various countries begin successively to reduce or stop to produce after 1973, but they still extensively exist in different surrounding mediums, enter biosome by different route of exposure, accumulate in the adipose tissue of humans and animals body and organ, more be difficult for draining, toxicity is just bigger.Its toxicity mainly shows as: influence skin, nerve, liver, destroy the metabolism of calcium, cause the infringement of bone, tooth, and have chronic carcinogenic and cause the possibility of hereditary variation etc.Therefore, the research of polychlorinated biphenyl pollutant in the biosome often being become the action of environment, food and hygiene department, will be the gordian technique that influences its quantitative test accuracy to separation, the purifying of this compounds.
The extraction detachment process of polychlorinated biphenyl is exactly that polychlorinated biphenyl and other composition are separated in the general biological specimen, thereby avoids interference phenomenons such as the background of generation or noise be excessive in testing process.Component to be measured through extracting contains the impurity similar to this component structure usually in the extract, with component to be measured and impurity separating process, this process is also referred to as " purification ".In the polychlorinated biphenyl leaching process of biological specimen, purification process is the technological difficulties of sample pre-treatment, also is to be related to the authenticity of testing result and the important step of detection method reliability.The main method of common purification process has solid phase extraction, liquid-liquid apportion design, method of chemical treatment, sweeps collection condistillation method, the cryogenic freezing method of purification, the preposition chromatographic column method of purification etc.Solid phase extraction is to use at present one of modal purification method, by adsorption column, distribute realizations such as post, gel permeation column, thin layer plate, its principle be the component to be measured of sample in chromatographic column, be adsorbed on the adsorbent with by the repetitive process of desorb.Adsorbent commonly used has Fo Luoli tripoli, aluminium oxide, activated charcoal, silica gel, magnesium oxide and cellulose etc.Liquid-liquid apportion design also is a kind of purification method very commonly used, and its principle is to utilize component to be measured one group of partition factor difference that immiscible solvent is internal, distributes by repeated multiple times, component to be measured is separated, to reach the purification purpose with impurity.Solvent commonly used is to the normal hexane distribution that the acetonitrile extract is arranged, the methenyl choloride distribution of acetonitrile extract, the sherwood oil distribution of acetone extract, the methylene chloride distribution of acetone extract etc.
The pre-treating method of polychlorinated biphenyl is decided according to different research media, as the polychlorinated biphenyl content in the research biological specimen, must consider the removal of complicated lipid, high molecular weight protein, organic acid or alkaloid etc.Relatively Chang Yong several pre-treating methods find that the liquid-liquid apportion design and the method for chemical treatment of polychlorinated biphenyl has certain defective usually, and they relatively consume solvent usually, and for chromatogram type solvent, a large amount of liquid-liquid distributes will increase certain experimental cost.On the other hand, also cause the loss of sample to be tested easily, cause the error of the recovery bigger, even, generally also will carry out separation and purification through follow-up column chromatography through after liquid-liquid distribution.Solid phase extraction also is common a kind of method, yet the solid-phase extraction column general cost is than higher, on solid-phase extraction column, before the sample, generally require sample to be purified must pass through certain pre-treatment, as acidic-group (COOH etc.) or basic group (NH being arranged by certain preprocessing process
2Deng) organic chaff interference remove, simultaneously solid phase extraction has strict requirement to the heap(ed) capacity of sample.
At present, do not find to realize the quick pretreatment and the purification process of polychlorinated biphenyl in the biological specimen as yet by the multistage modification method that changes chromatographic column filler.
Summary of the invention
The invention provides a kind of simple multistage improvement column that is used for biological specimen polychlorinated biphenyl quick pretreatment and purifying.
Multistage improvement column provided by the present invention comprises that the wash-out of conventional chromatogram post flows out the pressure portion of part, column packing part and sample introduction product, and described column packing part is made up of four parts, wherein, I in the cylinder is the neutral chromatography part partly, accounts for 20% of whole cylinder, and filler is a neutral silica gel;
II in the cylinder is neutral non-fat portion partly, accounts for 20% of whole cylinder, and the selection of column packing is decided according to concrete biomolecule;
III in the cylinder is the alkali modification part partly, accounts for 30% of whole cylinder, and column packing is alkaline hydrogen aluminium oxide, Fo Luoli tripoli or the material be made up of mixing such as magnesium oxide, aluminium oxide, and this part is mainly used in the compound that adsorbs organic acid securely;
IV in the cylinder partly is sour modification part, accounts for the 20-30% of whole cylinder, mainly refers to the strong acid modified silica-gel column packing of 3-6N;
And, being provided with dividing strip between the each several part in the filler cylinder, the IV part in the filler cylinder links to each other with the pressure portion of sample introduction product, and the I part in the filler cylinder flows out part with described wash-out and links to each other.
The filler selection principle of described multistage improvement column cylinder II part is for removing the material of macromolecule fat and micromolecule lipid, specifically can be: adopt filler, acticarbon filler and the cellulose wadding of C-18 to carry out a certain proportion of mixing etc., the recommendation blending ratio is C-18: the filler of acticarbon is 65%: 35%, or C-18: cellulose is 78%: 22%.
Composition weight ratio in the filler of described multistage improvement column cylinder III part can be silicon dioxide (82%): magnesium oxide (12%): aluminium oxide (5.7%): sodium sulphate (0.3%).
Strong acid in the filler of described multistage improvement column cylinder IV part is hydrochloric acid or sulfuric acid etc., and modifying process is: slowly add concentrated acid, slowly stir it with glass bar, place then and drain in the fuming cupboard, the time is more than 48 hours.
The filler particles thing size of described multistage improvement column all is controlled at unified scope.Select the particle of different-grain diameter for use for the main body of different size, as at the 100-220 order.Recommend to adopt dry column-packing during the dress post.
Also have dividing strip between four parts of described column packing, each dividing strip generally adopts neutral silica gel unanimous between the higher and lower levels, accounts for the 5-10% of whole cylinder, and the particle size must be with the modification part be consistent up and down, and error control is in 10%.
The material of the column jecket of described multistage improvement column is stainless steel, glass or organic glass family macromolecule polymkeric substance etc.; Size can change, and for example internal diameter is 28mm, and length is 100mm.
Another purpose of the present invention is to provide polychlorinated biphenyl in a kind of biological specimen to detect the method for quick pretreatment and purifying.
Fast processing of the present invention and purification process, the aforementioned multistage improvement column of main use, with the pressure portion charging of biological specimen from described multistage improvement column, pass through IV part, III part, II part and I part in the filler cylinder in regular turn, flow out biological specimen after part receives treated and purifying by wash-out.
Biological specimen can carry out pre-treatment before with multistage improvement column purifying of the present invention, polychlorinated biphenyl with the various biomolecules effect is discharged, the method of pre-treatment has technology such as acidolysis, wherein, acid hydrolysis method is: draw in the small beaker of serum in about 25ml about 2.5ml, slowly add 2-3ml left and right sides 12N hydrochloric acid, slowly jolting, treat that the bubble in the solution discharges, add 80-100 purpose silica gel then as adsorbent, freeze drying concentrates at low temperatures, and biomolecule and polychlorinated biphenyl are adsorbed on the silica gel equably.
Can adopt the solvent compression system during described charging, earlier with behind the solvent elution, and then sample introduction.
Adopt above scheme, the present invention can realize the quick pretreatment and the purifying of polychlorinated biphenyl by the multistage column filler of modification.In the pre-treatment process of some biological specimen, can replacement liquid-process that liquid distributes, thus avoid causing the loss of sample to be tested and the consumption of solvent, make sample pre-treatment process become simple effective.Multistage improvement column of the present invention can reach following purpose in polychlorinated biphenyl separation and purification process: 1) remove impurity detection architecture is disturbed; 2) removal of acid in the background in the complex environment; 3) removal of alkali in the background in the complex environment; 4) removal of biomacromolecule albumen in the complex environment.The multistage improvement column that is used for polychlorinated biphenyl quick pretreatment and purifying of the present invention obviously is better than prior art, has the high and low pollution of separation and purification efficient, to advantage such as the instrument and equipment requirement is low and with low cost, suits large area to popularize and uses.
Below in conjunction with specific embodiment the present invention is described in further details.
Description of drawings
Fig. 1 is the sectional view of multistage improvement column of the present invention
Fig. 2 is that the mark-on of polychlorinated biphenyl PCB-118 in the calf serum reclaims experimental result
Embodiment
Method therefor is conventional method if no special instructions among the following embodiment.
Embodiment: be used for the formation and the use of the multistage improvement column of biological specimen polychlorinated biphenyl quick pretreatment and purifying
One, the formation of multistage improvement column
As shown in Figure 1, with the internal diameter is 28mm, length is that the chromatographic column of the glass material of 100mm is the formation of example explanation multistage improvement column of the present invention, it comprises that the wash-out of conventional chromatogram post flows out the pressure portion of part, column packing part and sample introduction product, in the cylinder of described column packing part, comprise four parts of loading different fillers in regular turn, wherein:
I in the cylinder partly belongs to the neutral chromatography part, accounts for 20% of whole cylinder, and filler is 200 purpose neutral silica gels;
II in the cylinder partly belongs to neutral non-fat portion, account for 20% of whole cylinder, the selection of column packing is decided according to concrete biomolecule, selection principle is for removing the material of macromolecule fat and micromolecule lipid as far as possible, can be one or more the mixing in C-18, acticarbon and the cellulose, recommend mixed weight than being C-18: the filler of acticarbon is 65%: 35%, or C-18: cellulose is 78%: 22%.The particle diameter of column packing is about 200 orders; This part is mainly used in sloughs big molecule lipoprotein and micromolecular grease class;
III in the cylinder partly belongs to the alkali modification part, account for 30% of whole cylinder, column packing is alkaline hydrogen aluminium oxide, Fo Luoli tripoli or the material be made up of mixing such as magnesium oxide, aluminium oxide, the composition of pressing filler calculates, and weight ratio can be silicon dioxide (82%): magnesium oxide (12%): aluminium oxide (5.7%): sodium sulphate (0.3%).This part condiment particle diameter is about 200 orders, and this part is mainly used in the compound that adsorbs organic acid securely;
IV in the cylinder partly belongs to sour modification part, accounts for the 20-30% of whole cylinder, and with the hydrochloric acid modified silica-gel column packing of 6N, particle diameter is about 200 orders; Filler modified process is: slowly add concentrated hydrochloric acid, slowly stir it with glass bar, place in the fuming cupboard then and drain, the time is more than 48 hours.
Also has dividing strip between four parts of described column packing, each dividing strip generally adopts neutral silica gel unanimous between the higher and lower levels, accounts for the 5-10% of whole cylinder, and the particle size is 200 orders, must be consistent with adjacent upper and lower part filler sizes, error control is in 10%.
IV part in the filler cylinder links to each other with the pressure portion of sample introduction product, and the I part in the filler cylinder flows out part with described wash-out and links to each other.
Adopt vacuum method to carry out dry column-packing.The process of dress post guarantees evenly as far as possible, consistent in density.
Thus, obtain multistage improvement column of the present invention.
Multistage improvement column of the present invention adopts the structure of foregoing description to constitute, but the big I of its size, packing volume and filler particles changes according to applicable cases, is not subjected to the restriction of foregoing description.For example, to the packing volume range of control of multistage improvement column (microtrabeculae): the microtrabeculae packing volume of 3.0mL is 0.6mL in general, and the microtrabeculae packing volume of 5.0mL is 1.0mL; 200 purpose fillers are used in the microtrabeculae suggestion of the big minor control field of filler particles thing to multistage improvement column (microtrabeculae): 5.0-10mL, less than the filler within the microtrabeculae filler suggestion use 100-120 order of 3.0mL; To the size of multistage improvement column (microtrabeculae) itself, if the sample≤2.5mL that detects, suggestion is with the microtrabeculae of 5.0-10mL, if the sample≤1.0mL that detects advises the microtrabeculae with 3.0mL.
Two, the use of multistage improvement column
The mark-on that detects polychlorinated biphenyl PCB-118 in the calf serum reclaims experiment, gets 2 milliliters calf serum, adds the PCB-118 of 500 μ g/L, and with GC-ECD method detection content wherein, concrete grammar may further comprise the steps:
1, pre-treatment
Biological specimen (add PCB-118 calf serum) is in that (this example uses internal diameter to be 28mm with multistage improvement column of the present invention, length is 100mm) need carry out pre-treatment before the purifying, polychlorinated biphenyl with the various biomolecules effect is discharged, the method of pre-treatment has acidolysis, technology such as pyrolysis, this example adopts acidolysis to handle: draw in the small beaker of serum in about 25ml about 2.5ml, slowly add 2-3ml left and right sides 12N hydrochloric acid, slowly jolting, treat that the bubble in the solution discharges, add 80-100 purpose silica gel then as adsorbent, freeze drying concentrates at low temperatures, and biomolecule and polychlorinated biphenyl are adsorbed on the silica gel equably.
2, detect
Adopt the solvent compression system during charging, earlier with behind the solvent elution, and then sample introduction, promptly carry out wash-out with the chromatographic grade normal hexane, receive leading portion wash-out part, the reception volume is 25mL, after concentrating, detects with gas chromatography-electron capture detector (ECD).
Key instrument Germany IKA_RV10 Rotary Evaporators; Agilent Technologies GC-7890 gas chromatograph (U.S. Agilent company), the 7683B automatic sampler; Electron capture detector (ECD); The accelerated solvent extraction Accelerated Solvent Extractor of U.S. Dionex Dai An company (ASE300 type).
The GC-ECD analysis condition:
With the gas chromatograph that has electron capture detector (model 7890, Agilent technologies company), the DB-XLB capillary chromatographic column is measured the PCBs compounds content.GC-ECD analysis condition: 250 ℃ of injector temperatures, split sampling (not shunting time 1min) not, sample size 1 μ l, constant voltage control, carrier gas (high-purity N
2) pressure 105kPa, 310 ℃ of detecting device ECD temperature, tail wind drift amount 40mLmin-1.Post oven temperature, degree: temperature programme, 95 ℃ of initial temperatures keep 2min; With 10 ℃ of min
-1Rise to 180 ℃, keep 3min; With 5 ℃ of min
-1Rise to 280 ℃, kept 5 minutes; With 20 ℃ of min
-1Rise to 300 ℃, kept 10.5 minutes.
3, result
The stratographic analysis result as shown in Figure 2, wherein, the position that is in retention time 3-12min peak is generally the impurity parts such as fat in the biological specimen, retention time is that 15.737 position is the peak of PCB-118 in this figure.If adopt other disposal route, the fat at retention time 3-12min peak goes out the peak position baseline and can raise, and the absorption signal at assorted peak and the baseline of rising mix, and will produce bigger interference to sample to be tested.Processing by multistage improvement column, as can be seen from Figure 2 the fat at retention time 3-12min peak goes out the peak position baseline and reduces greatly, the absorption at plurality of impurities peak also obviously descends and obtains separating effect preferably, show that multistage improvement column of the present invention can be used in the plurality of impurities removal in the biological specimen, can access separating resulting preferably when detecting PCB.Simultaneously, use this multistage improvement column to record the PCB-118 recovery in the 92%-101% scope, illustrate that this multistage improvement column by to sample quick pretreatment and purifying, can keep the higher recovery of PCB.
Though the present invention is described by previous embodiment, but because of different polychlorinated biphenyl may have the different recovery because of the difference that contains amount of chlorine atom, containing lipid in the different biological specimens can be different, therefore, can not break away under the spirit of the present invention and do some variations and remove chaff interference targetedly by simple experiment, these possible changing contents also belong to the present invention.The previous experiments process is the rational using method of one of the present invention, one of the mode that can specifically implement for the present invention only, but not as limit.
Compare for biological specimen polychlorinated biphenyl quick pretreatment and purification process with multistage improvement column of the present invention and other, operating process is more as shown in table 1:
Table 1 distinct methods process relatively
|
The adsorption target molecule |
Flow process |
Adsorbent |
Target |
Multistage improvement column of the present invention |
Disturbing molecule |
Similar normal phase column chromatography |
Multiple through the composite adsorbing material after the modification |
Remove interference/matrix effect |
Solid-phase extraction column |
Molecule to be checked |
Earlier absorption, rear wash-out |
The single kind |
Purify/concentrate |
Liquid-liquid distributes extraction |
Do not have |
Repeatedly extraction, liquid-liquid distributes |
Do not have |
Purify/concentrate |
Listed process can be found out from table, uses solid-phase extraction column cost height (being worth 80 yuan to 100 yuan such as a solid phase extraction column) in other method, and can only use once, and the solvent elution system requirements is relatively harsh, and the sample load is littler; The shortcomings such as and liquid-liquid distributes often complex operation of extraction, and the rate of recovery is lower. And it is relatively simple to use multistage improvement column of the present invention to process, processing, one step of purge process finish, some interfering materials, be easier to remove (referring to Fig. 2) such as big molecule lipid geometric ratio, have the high and low pollution of separation and purification efficient, to the advantage such as the instrument and equipment requirement is low and with low cost, suit large area to popularize and use.