title: An interlaboratory investigation on the use of high-performance thin layer chromatography to perform assays of lamivudine-zidovudine, metronidazole, nevirapine, and quinine composite samples.
abstract: Two laboratories extensively investigated the use of HPTLC to perform assays on lamivudine-zidovudine, metronidazole, nevirapine, and quinine composite samples. To minimize the effects of differences in analysts' technique, the laboratories conducted the study with automatic sample application devices in conjunction with variable-wavelength scanning densitometers to evaluate the plates. The HPTLC procedures used relatively innocuous, inexpensive, and readily available chromatography solvents used in the Kenyon or the Global Pharma Health Fund Minilabs TLC methods. The use of automatic sample applications in conjunction with variable- wavelength scanning densitometry demonstrated an average repeatability or within-laboratory RSD of 1.90%, with 73% less than 2% and 97% at 2.60% or less, and an average reproducibility or among-laboratory RSD of 2.74%.
authors.affiliation: Muhimbili University of Health and Allied Sciences, School of Pharmacy, Laboratory for Pharmaceutical Analysis, PO Box 65013, Dares Salaam, Tanzania. elia.kaale@muhas.ac.tz
authors.forename: Eliangiringa
authors.initials: E
authors.lastname: Kaale
authors.forename: Peter
authors.initials: P
authors.lastname: Risha
authors.forename: Eike
authors.initials: E
authors.lastname: Reich
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Layloff
mesh_terms: D019380:Anti-HIV Agents / Q000032:analysis*; D000962:Antimalarials / Q000032:analysis*; D000994:Antitrichomonal Agents / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003720:Densitometry; D004338:Drug Combinations; D019259:Lamivudine / Q000032:analysis*; D008795:Metronidazole / Q000032:analysis*; D019829:Nevirapine / Q000032:analysis*; D011803:Quinine / Q000032:analysis*; D012015:Reference Standards; D012997:Solvents; D013056:Spectrophotometry, Ultraviolet; D015215:Zidovudine / Q000032:analysis*
chemical_list: D019380:Anti-HIV Agents; D000962:Antimalarials; D000994:Antitrichomonal Agents; D004338:Drug Combinations; D012997:Solvents; C109078:lamivudine, zidovudine drug combination; D008795:Metronidazole; D019259:Lamivudine; D015215:Zidovudine; D019829:Nevirapine; D011803:Quinine