An isocratic reversed-phase high-performance liquid chromatography (RP-HPLC) method has been developed for rapid and simultaneous separation and estimation of 3 antidiabetic drugs, namely, metformin, pioglitazone, and glimepiride, in human plasma within 3 min. Separation was carried out on a MAGELLEN 5U C₁₈ (5 μm, 150 mm × 4.60 mm) using a mobile phase of MeOH–0.025 M KH₂PO₄ adjusted to pH 3.20 using ortho-phosphoric acid (85:15, v/v) at ambient temperature. The flow rate was 1 mL/min, and the maximum absorption was measured at 235 nm. The retention time of metformin, pioglitazone, and glimepiride was noted to be 1.24, 2.32, and 2.77 min, respectively, indicating a very short analysis time compared to that of other reported methods. Also, limits of detection were reported to be 0.05, 0.26, and 0.10 μg/mL for metformin, pioglitazone, and glimepiride, respectively, showing a high degree of method sensitivity. The method was then validated according to the FDA guidelines for the determination of the three drugs clinically in human plasma, in particular, regarding pharmacokinetic and bioequivalence simulation studies.

A high performance liquid chromatography method had been developed and validated for rapid simultaneous separation and determination of three anti-helicobacter drugs, oxytetracycline (OXY), tinidazole (TIN) and esomeprazole (ESM) in human plasma within 6 minutes. Drugs extraction method from plasma was based on protein precipitation technique. Separation was carried out on a Equisil BDS C18 column (5 μm, 150 × 4.60 mm) using a mobile phase of acetonitrile: 0.025 M KH2PO4 (25: 75, v/v) adjusted to pH 3.50 with ortho-phosphoric acid at ambient temperature. The flow rate was 1 mL/min and maximum absorption was measured using Diode Array (DAD) detector at 285 nm. The retention times of OXY, TIN and ESM were recorded to be 2.68, 3.52 and 5.17 minutes, respectively, indicating a shorter analysis time. Limits of detection were also reported to be 0.10, 0.07 and 0.04 μg/mL for OXY, TIN and ESM, respectively, showing a high degree of the method sensitivity. The method was then validated according to FDA guidelines for the determination of the drugs clinically in human plasma specially regarding pharmacokinetic and bioequivalence studies.

An isocratic RP-HPLC method has been developed for rapid and simultaneous separation and estimation of three antidiabetics drugs, metformin, gliclazide and glimepiride in tablet dosage forms within 6 minutes. Separation was carried out on a Thermo Scientific® BDS Hypersil C8 column (5µm, 2.50 x 4.60 mm) using a mobile phase of MeOH : 0.025M KH2PO4 adjusted to pH 3.20 using ortho - phosphoric acid (70 : 30, v/v) at ambient temperature. The flow rate was 1 mL/min and UV detection was set at 235 nm. The retention time of metformin, gliclazide and glimepiride was noted to be 3.06, 4.33 and 6.00 minutes respectively, indicating a very short analysis time rather than other reported methods. Also, limits of detection were reported to be 0.05, 1.21 and 0.11 µg/mL for metformin, gliclazide and glimepiride, respectively, showing a high degree of the method sensitivity. The method was then validated according to ICH guidelines where it was found to be accurate, reproducible and robust. Finally, the method was compared statistically with reference methods indicating that there is no significant difference between them in respect of precision and accuracy.

А grаdiеnt HPLC mеthоd was dеvеlоpеd аnd vаlidаtеd fоr rаpid simultаnеоus sеpаrаtiоn аnd dеtеrminаtiоn оf the following eight drugs оf sаrtаn аnd stаtin clаssеs in thеir purе аnd dоsаgе fоrms within 15 minutes: irbеsаrtаn (IRB), lоsаrtаn (LОS), vаlsаrtаn (VАL), оlmеsаrtаn (ОLM), rоsuvаstаtin (RОS), аtоrvаstаtin (АTR), lоvаstаtin (LОV), аnd simvаstаtin (SIM). Sеpаrаtiоn wаs cаrriеd оut оn а Kinеtеx C₁₈ 100А cоlumn (2.60 m, 4.60 mm × 100 mm) using а grаdiаnt binаrу mоbilе phаsе оf 0.05M pоtаssium dihуdrоgеn phоsphаtе buffеr (pH 3.50 аdjustеd bу оrthо-phоsphоric аcid) аnd аcеtоnitrilе аt rооm tеmpеrаturе. Thе flоw rаtе wаs 1.00 mL/min аnd mаximum аbsоrptiоn wаs mеаsurеd using a DАD dеtеctоr аt 280 nm. Thе rеtеntiоn timеs оf IRB, LОS, RОS, VАL, АTR, LОV, ОLM, аnd SIM wеrе rеcоrdеd tо bе 4.72, 5.32, 6.06, 7.19, 7.96, 9.30, 11.91, аnd 14.66 minutеs, rеspеctivеlу. Limits оf dеtеctiоn wеrе rеpоrtеd tо bе 2.01, 1.32, 1.10, 0.76, 0.21, 1.50, 0.38, аnd 0.55 mM fоr thе sаmе sеquеncе оf drugs, rеspеctivеlу, shоwing а high dеgrее оf mеthоd sеnsitivitу. Thе mеthоd wаs thеn vаlidаtеd аccоrding tо the intеrnаtiоnаl cоnfеrеncе оf hаrmоnizаtiоn (ICH) guidеlinеs fоr thе dеtеrminаtiоn оf thе drugs in thеir dоsаgе fоrms with highlу prеcisе rеcоvеriеs. Аlsо, a stаtisticаl cоmpаrisоn with rеfеrеncе mеthоds wаs pеrfоrmеd shоwing nо significаnt diffеrеncеs bеtwееn thе prоpоsеd mеthоd аnd rеpоrtеd оnеs in tеrms оf prеcisiоn аnd аccurаcу.