Study On Rapid Screening Of Illegal Additives In Nutritional Supplements By Ion Mobility Spectrometry

With the consumption of nutritional supplements gradually increasing,people pay more attention to the safety of nutritional supplements.Nutritional supplements' special position in the market results in a handsome profit.Driven by interests,there are plenty of nutritional supplements on the market with illegally added chemicals.Liquid chromatography tandem mass spectrometry has been used in nutritional supplements,but it's necessary to develop novel rapid screening technology because of numerous sample.As a traditional screening tool,ion mobility spectrometry has been widely used in the detection of explosives and drugs.Thus,in this paper,ion mobility spectrometry was used to detect the illegal additives in nutritional supplements.(1)In this paper,a method based on direct-immersion single drop micro-extraction(DI-SDME)coupled with ion mobility spectrometry(IMS)for screening of benzodiazepines in nutritional supplements was developed.This method combining the advantages of DI-SDME and IMS is simple,fast,green and suitable for on-site analysis.Especially,DI-SDME sampling method could minimum the memory effect of sample on IMS.The parameters of IMS instrument and the parameter of DI-SDME were optimized by the univariate approach.Under optimal experimental conditions,this method shows low limits of detection(down to 30 ng/mL),high enrichment factors(57?259),good repeatability(with relative standard deviation lower than 9%),linear dynamic range of 100?3000 ng/mL and relative recoveries ranging from 62%to 106%.The results proved that DI-SDME-IMS system can successfully screen five BZDs in nutritional supplements.As far as we know,this is the first reported to screen the illegally additives by the DI-SDME-IMS.(2)In this paper,ion mobility spectrometry followed by dispersive liquid-liquid micro-extraction(DLLME-IMS)as a rapid screening method was successfully applied to detect dimethyl phthalate(DMP),diethyl phthalate(DEP),dibutyl phthalate(DBP)and benzyl butyl phthalate(BBP)in the capsule.Through the optimization of extraction conditions,20 ?L chloroform and 400?L acetone was used to extract PAEs in 8 mL aqueous solution.In the pre-processing method,there was huge specific surface area between extraction solvent and analytes driven by dispersive solvent,which contributed to extraction equilibrium in a short time and high enrichment factors.Under optimal experimental conditions,this method shows low limits of detection(down to 10 ng/mL),high enrichment factors(57-333),good repeatability(with relative standard deviation lower than 9%).What's more,simple equipment,low cost and high-performance make is possible to popularize.Compared with traditional detection technology such as liquid chromatography coupled with mass spectrometry(LC-MS)and gas chromatography coupled with flame ionization detector(GC-FID),there was relatively large impact by matrix,which resulted in low recovery in low level concentration sample.Therefore,good precision indicated this method was competent for rapid screening of phthalate esters(PAEs)in the capsule.