The Research Of The Solid Phase Microextraction (SPME) For The Determination Of The Volatile Organic Chemicals In The Biological Specimens

ObjectivesThe solid-phase microextraction(SPME)utilizes the fused quartz fiber which is coated on adsorbing material to absorb the organics in the samples to achieve the purpose of extraction and concentration.It haves the characteristic of no-solvent, direct sample introduction,convenient and shortcut to manipulate and sensitive and it overcomes the weakness of the orthodox sample pre-processing technical.SPME integrates the sampling,extraction,enriching and injection in one step,it is convenient to manipulate,analysis cycle is short,few dosage of sample is used,the reproducibility is good,and it is easy to be automatic so it is fit for analysis on the spot particularly,little organic solvent used is profit for the healthy of analytical personnel,and the secondary pollution to environment is to exempt.In this experiment,the newest SPME technology was applied to biological monitoring in occupational health.Based on the development,principle and type of the solid-phase microextraction,the SPME installation was developed and the developing methods of the fiber coating was researched emphasizily.The coatings fit for the determination of acetone in urine and styrene in blood were screened.The SPME detection methods of the determination for acetone in urine and styrene in blood were institute.Then the methods researched will be reported as biological monitoring standard methods in occupational health for utilizing in the occupational health technical service departments in the whole country.Methods1.The manufacture of the SPME installation:according to the principle of the SPME,design the SPME installation.The selection of the coating materials and the approach for manufacture technology:select the coating materials referring to acetone in the urine and styrene in the blood according to the principle that the organics and solvents similar were compatible.The coating thickness and the coating methods fit for the metabolic product above mentioned by changing the concentration of the coating solution,coating time,coating number of times to alter the coating thickness.2.The technology research of solid-phase microextraction for determining acetone in the urine and styrene in the blood:the selection of sample size, container volume,extraction time,extraction temperature,stirring style and velocity.3.The selection of GC condition connecting with SPME:including the selection of the type of the chromatographic column,the column temperature,the inject opening temperature,the detector temperature,and the definition of the adsorption temperature,adsorption time,adsorption solvent.4.Technology validation by selecting the workers contacting with the poisons such as acetone,styrene and so on,at the same time comparison by determining the blank sample.Results1.The self-made SPME extraction installation was made easily and used conveniently.The extraction coating PDMS was effective to extract acetone in urine and styrene in blood,the coating was coated for thrice,the concentration of the coating solution was 50g/L,and 6%curing agent was added in,at that time,the effect was good,and the extraction time was suitable.The PDMS coating thickness was 120μm measured by the microscope.2.The optimal condition of SPME for determining acetone in urine was as follows: 4gNa₂SO₄,the extraction temperature was 30℃,the extraction time was 5min,the rotation speed was brachytely,the ratio of sample volume and headspace vacuity was 1:3,the desorption temperature was 250℃,the desorption time was 5min.The linear correlation for acetone in urine was good in 0.0～150.0μg/ml,and the equation was Y =3.55X+3.05,r=0.9990,the detection limit 0.0008μg/ml,the precision was good,the recovery was greater than 90.7%.The urine sample can be kept for 14 days at 4℃.The common possible coexistence agent of the acetone in the environment dichloromethane, 2-butanone,methanol,acetic ether and the basal body in urine all didn't interfere with the determination of the acetone in urine.The acetone contents of the 30 contact persons and 10 non-contact persons were determined by this method.The acetone contents of the contact persons were form 0.04μg/ml to 62.97μg/ml,the acetone contents of the non-contact persons were all lower than the detection limit.The experiment indicated SPME-GC refers to the determination of the acetone in urine.3.The optimal condition of SPME for determining styrene in blood was as follows: 15 H₃PO₄μL/2ml blood,the extraction temperature was 20℃,the extraction time was 10min,the rotation speed was the middle speed,the ratio of sample volume and headspace vacuity was 1:4.The desorption temperature was 250℃,the desorption time was 5min.The linear correlation for acetone in urine was good in 0.00～1.65μg/ml, and the equation was Y=187.24X-2.1059,r=0.9994,the detection limit 0.0006μg/ml, the precision was good,the recovery was greater than 77.0%.The urine sample can be kept for 14 days at 4℃and-8℃.The common possible coexistence agent of the styrene in the environment styrene benzene,toluene,ethyl benzene,xylene,ethylene tetrachloride and the basal body in blood all didn't interfere with the determination of the styrene in blood.The styrene contents of the 30 contact persons and 10 non-contact persons were determined by this method.The styrene contents of the contact persons were form 0.024μg/ml to 0.58μg/ml,the styrene contents of the non-contact persons were all lower than the detection limit.The experiment indicated SPME-GC refers to the determination of the styrene in blood.Conclusions1.The article mainly manufactured SPME installation and fiber coating,based on the principle of the SPME technology,which have the characteristic of the similar enriching capability,cheap and simple preparation technology compared with SPME installation and fiber coating in commerce.2.The determination methods of acetone,benzene,toluene in urine and styrene in blood were researched to standardize by using the self-made SPME installation. According to WS/T 68-1996 the development norm of the biomaterial analytical method(urine and blood),The results indicated that the indexs of the methods researched were all coincidence with the development norm,so they can be reported as biological monitoring standard methods in occupational health for utilizing in the occupational health technical service departments in the whole country.