Hypoglycemic Drug Gliclazide And Compound Pioglitazone Rosiglitazone Metformin Human Pharmacokinetic Study

ChapterⅠDetermination of Gliclazide by LC-MS/MS andPharmacokinetics of Gliclazide in Human FollowingSingle Oral AdministrationDetermination of glicla zide in huma n plasma and its bioeq uivalence study:asimple, sensitive and selective LC-MS/MS method for the quantification ofglicla zide in huma n plasma has been develo ped and valida ted and applied to thestudy of pharmacok inetics of glicla zide in healthy volunteers.Glicla zide and glipizide (internal standard, IS) were isola ted from huma nplasma by extraction with methanol, chromatographed on a Lichrospher C₁₈column with a mobile phase consisting of 10mmol·L^-1 ammonium acetate and0.2% acetic acid : methanol (10:90, v/v), and detected using a tandem massspectrometer with an electrospray ioniza tion interface. LC-MS/MS (ESI) wasperformed by using selected reaction monitoring (SRM) with ion transitions ofm/z 324 to 127.2 for glicla zide , m/z 446 to 321.1 for glipizide. The lower limit ofquantification (LLOQ) was 0.03μg·mL^-1and the assay exhibited a linear dynamicrange of 0.03 - 10.0μg·mL^-1 (r=0.9999). The extraction recovery was more tha n75.0%, the relative recovery was 82.3%～109.5%,The inter and intra dayprecision was good with the RSD<15.0%.The method was successfully applied to investigate the bioeq uivalence betweentwo kinds of tablets (reference versus test product) in 20 healthy ma le Chinesevolunteers. After a single 80 mg dose for the reference and test product, theresulting mea ns of major pharmacok inetic parameters such as AUC0–t, AUC0?∞,Cmax, Tmax and t1/2 of glicla zide were (82.00±38.15μg·h·mL^-1 versus 80.93±34.54 μg·h·mL^-1), (93.53±60.55μg·h·mL^-1 versus 93.81±50.32μg·h·mL^-1), (4.24±0.96μg·mL^-1 versus 4.21±0.99μg·mL^-1), (3.6±1.2 h versus 4.1±1.2 h) and(17.07±6.48 h versus 17.90±7.00 h), respectively, indica ting that these two kindsof tablets were bioeq uivalent.ChapterⅡStudy on the Pharmacokinetics of Compound PioglitazoneMetformin Tablet in Healthy VolunteersA HPLC-UV method and a LC-MS method for the determination ofpioglita zone and metformin in huma n plasma has been developed and valida ted,respectively, and investigated the pharmacok inetics of pioglita zone andmetformin after oral administration of compound pioglita zone metformin tablet.The ma in pharmacok inetic parameters of pioglita zone and metformin werecompared by those reported domest ic and abroad in order to evaluate druginteraction.HPLC method was developed for the determination of pioglita zone in huma nplasma, ibuprofen was used as an internal standard. After a simple liq uid-liq uidextraction with ether-methylene chloride (4:1, v/v), pioglita zone and the internalstandard ibuprofen were separated on a Hedera C₁₈ column. The mobile phase wasacetonitrile: 20 mmol·L^-1 ammonium acetate buffer solution (55:45, v/v) and runat a flow rate of 1.0 ml·min^-1. The column effluent was monitored by a UVdetector set at 225 nm. No interferences from endogenous substa nces were found.The detection limit for pioglita zone in huma n plasma was 25 ng·mL^-1, and linearover a concentration range from 25 to 2000 ng·mL^-1. The coefficients of variation of the assay were genera lly low (below 10.0%) for huma n plasma, the extractionrecovery was 81.2～99.0%; the relative recovery was 88.0%～104.5%,pioglita zone was stable for 4 h under room temperature, three freeze(4°C)-thaw(a mbient) cycles and stable for 21days under 4°C.A LC-MS method was developed for the determination of metformin in huma nplasma, pseudoephedrine was used as an internal standard. After a simpledeproteiniza tion, metformin and the internal standard pseudoephedrine wereseparated on a Shim-park CLC-CN column and detected by mass spectrometry.The mobile phase was methanol : water containing 2mmol·L^-1 ammonium acetateand 0.3% formic acid (56:44, v/v); metformin was determined with eletrospra yioniza tion-mass spectrometry (ESI-MS) in the selected ion monitoring (SIM)mode using target ions at [M+H]+ m/z 129.9 for metformin and [M+H]+ m/z 147.9for pseudoephedrine. No interferences from endogenous substa nces were found.The detection limit for metformin in huma n plasma was 0.05μg·mL^-1 and linearover a concentration range from 0.05 to 5.0μg·mL^-1. The coefficients of variationof the assay were genera lly low (below 15.0%) for huma n plasma, the extractionrecovery was 82.4～99.6％, the relative recovery was 88.0％～104.3％,pioglita zone was stable for 6 h under room temperature, three freeze (4°C)-thaw(ambient) cycles and stable for 27days under -60°C.The ma in pharmacok inetic parameters of pioglita zone and metformin werecompared by those reported domestic and abroad, there was no significa nt druginteraction between pioglita zone and metformin.