Validation of a liquid chromatographic/tandem mass spectrometric method for the determination of scopolamine butylbromide in human plasma: application of the method to a bioequivalence study.
A sensitive and specific LC/MS/MS method was developed and validated for the determination of scopolamine butylbromide in human plasma. Scopolamine butylbromide and propanolol (internal standard) were extracted from the plasma by liquid-liquid extraction with dichloromethane as the extraction solvent and separated on a C18 analytical column (50 x 4.6 mm id) maintained at 40 degrees C. The analytes were eluted at a constant flow rate of 0.45 mL/min; the mobile phase consisted of acetonitrile and a buffer of 5 mM ammonium acetate and 0.1% formic acid (60 + 40, v/v). The mass spectrometer, equipped with an electrospray source in the positive ionization mode, was set up in the multiple-reaction monitoring mode to monitor the transitions m/z 360.6 > 102.5 (scopolamine butylbromide) and m/z 259.7 > 115.6 (propanolol). The chromatographic separation was obtained within 2.0 min, and the responses were linear over the concentration range of 0.10-40.00 ng/mL. The mean extraction recoveries of scopolamine butylbromide and propanolol from plasma were 69.00 and 80.76%, respectively. Method validation parameters, such as specificity, linearity, precision, accuracy, and stability, were within the acceptable range. Moreover, when the proposed method was successfully applied to a pharmacokinetic study of healthy human volunteers, the results showed that the two scopolamine butylbromide formulations tested are not bioequivalent in rate and extent of absorption.
Manfio
Josélia Larger
JL
BIOCINESE, Centro de Estudos Biofarmacêuticos, Av. Cirne Lima, 1541, 97.105-900--Toledo-PR, Brazil. manfiojoselia@bol.com.br
Dos Santos
Mauricio Bedim
MB
Favreto
Wagner Alex Jann
WA
Hoffmann
Fabiane Ines
FI
Mertin
Adriana Cristina
AC
D000085:Acetates / Q000032:analysis; D000293:Adolescent; D000328:Adult; D002623:Chemistry Techniques, Analytical; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods*; D005260:Female; D005561:Formates / Q000032:analysis; D006801:Humans; D006842:Hydrocarbons, Brominated / Q000032:analysis* / Q000097:blood*; D008297:Male; D010949:Plasma / Q000187:drug effects; D015203:Reproducibility of Results; D012601:Scopolamine / Q000032:analysis* / Q000097:blood*; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013696:Temperature
D000085:Acetates; D005561:Formates; D006842:Hydrocarbons, Brominated; D012997:Solvents; C030544:formic acid; D012601:Scopolamine; C018824:ammonium acetate; C047757:butyl bromide