title: Simultaneous determination of 38 phosphodiestrase-5 inhibitors in illicit erectile dysfunction products by liquid chromatography-electrospray ionization-tandem mass spectrometry.
abstract: This paper describes the development and validation of simultaneous analytical method for 38 compounds, sildenafil, tadalafil, vardenafil and their analogues in illicit erectile dysfunction (ED) products by the liquid chromatography-electrospray ionization-tandem mass method (LC-ESI-MS/MS). Chromatographic separation was performed on a C18 reversed-phase column using a gradient of solvent A: aqueous 2 mM ammonium formate solution and solvent B: acetonitrile (ACN). All components were monitored under time-scheduled multiple reaction monitoring (MRM) mode. The limits of detection (LOD) ranged from 0.004 ng/ml to 0.455 ng/ml and the limits of quantification (LOQ) ranged from 0.012 ng/ml to 1.5 ng/ml. Calibration curves were linear with correlation coefficients over 0.9991. Mean recoveries ranged from 73.6% to 111.3%, and relative standard deviation (RSD) was less than 10%. The intra- and inter-day precision ranged from 0.2% to 16.3% and from 0.2% to 17.0%, respectively. The proposed method was applied to investigate the 52 illicit ED products.
authors.affiliation: Advanced Analysis Team, Toxicological Evaluation and Research Department, National Institute of Food and Drug Safety Evaluation, Korea Food & Drug Administration, Osong Health Technology Administration Complex, 187 Osongsaengmyeong2-ro, Yeonje-ri, Osongeup, Cheongwon-gun, Chungcheongbuk-do 363-700, Republic of Korea.
authors.forename: Eung-Sun
authors.initials: ES
authors.lastname: Lee
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Kyoung Moon
authors.initials: KM
authors.lastname: Han
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Kim
authors.forename: In Sun
authors.initials: IS
authors.lastname: Hwang
authors.forename: Sooyeul
authors.initials: S
authors.lastname: Cho
authors.forename: Soon Young
authors.initials: SY
authors.lastname: Han
authors.forename: Jinho
authors.initials: J
authors.lastname: Kim
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D007172:Erectile Dysfunction / Q000139:chemically induced*; D006801:Humans; D013287:Illicit Drugs / Q000009:adverse effects* / Q000737:chemistry*; D008297:Male; D058986:Phosphodiesterase 5 Inhibitors / Q000009:adverse effects / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D015813:Substance Abuse Detection / Q000379:methods*; D053719:Tandem Mass Spectrometry
chemical_list: D013287:Illicit Drugs; D058986:Phosphodiesterase 5 Inhibitors