| Stilbenes estrogens conclude diethylstilbestrol(DES),hexestrol(HES)and dienestrol(DIS)are typical synthetic non-steroid estrogens.And they have similar pharmacological action with estradiol,commonly used for treating estrogen deficiency and infertility in food animals.In addition,the above estrogens can improve the feed conversion rate and promote the animal growth.In particular,diethylstilbestrol was used widely as a typical growth promoter in animal husbandry.However,relative research found that they can remain in tissues of edible animals and enter human body through food chain and interfere with the normal functions of the endocrine systems,even have potential carcinogenicity for human being and could induce breast cancer and prostate cancer.Furthermore,it could also pollute environmental water through sewage systems.Therefore,it is of great importance to establish a rapid,sensitive,simple,effective residue analysis method to guarantee the safety of animal derived food and environmental water.The study developed an emerging environmental-friendly sample pretreatment method-immunoaffinity solid phase microextraction(SPME)by preparing the immunnoaffinity SPME rods which can purify 3 stilbenes estrogens from complicated matrix.The immunoaffinity SPME device was built with three stainless steel rods bundled together as one and modified with porous silicate particles by potassium silicate,antibody immobilization approach was employed based on the covalent attachment of the anti-diethylstilbestrol monoclonal antibody(m Ab)onto the rods.The immunoaffinity SPME rod was characterized and confirmed by scanning electron microscopy and X-ray photoelectron spectroscopy analysis.The porous network showed a very large active surface area and significantly increased the adsorption capacity for stilbenes estrogens.Moreover,the immunoaffinity sorbent showed good sturdiness at least 10 times with stable extraction performance.The main experimental parameters were optimized and the optimized results were: extraction time is 30 min;desorption time is 20 min;rotation rate is 100 rpm;desorption solution is absolute methanol;the volume of desorption solution is 1m L.Under the optimized conditions,the adsorption volume for 3 stilbenes estrogens DES,HES,DIS were 49.6 pmol/cm2,44.6 pmol/cm2 and 23.8 pmol/cm2 respectively.The change curves of the adsorption volume of immunoaffinity SPME along with the number of usage cycles at different intervals were explored.The results showed that the immunoaffinity SPME rods remained 58% of its initial adsorption capacity,and the effection of intervals to the adsorption volume was no striking difference.A new method for determination of 3 stilbenes estrogens in environmental water samples using immunoaffinity SPME rods and UPLC-MS/MS technique was developed.Water samples were filtered through 0.22 μm cellulose filters,and then purified by immunoaffinity SPME rods under the optimized conditions.The analytes were separated by HSS T3 reversed phase C18 column and eluted with acetonitrile and water in isocratic elution.Multiple reaction monitoring(MRM)and negative ions mode was employed,and the water samples were quantified using external standard method with the matrix matched standard calibration curve.Good linearities were obtained for the 3 stilbenes estrogens at the concentration of 0.05~50 ng/m L with the linear relative coefficients ranging from 0.996 to 0.999;the limits of detection(LOD)for 3 estrogens was ranging from 0.05 to 0.15 ng/m L,and the limits of quantification(LOQ)for them was 0.5 ng/m L.The average recoveries at three levels of spiked concentrations(0.5,1,5 ng/m L)ranged from 34.2% to 62.7% were achieved,good intra-day and inter-day precision ranging from 7.8% to 12.7% and from 8.2% to 13.5% respectively.The newly developed immunoaffinity SPME showed high adsorption capacity,good sensitivity and reproducibility and was successfully applied to the analysis of DES,HES and DIS in environmental water samples. |
PDF Full Text Request