title: Time resolved analysis of risperidone and 9-hydroxy-risperidone in hair using LC/MS-MS.
abstract: Risperidone (RSP) is a second generation anti-psychotic drug used for the treatment of schizophrenia and anxiety disorders. In the last decades, clinical applications of hair analysis have received an increasing attention, because of its wide surveillance window. In this work, we describe a simple and fast method for detection and quantification of RSP and its major metabolite, 9-OH-risperidone (9-OH-RSP), in human hair. The validated method (cv of interday precision, intraday precision and accuracy<15%, r(2) of the calibration curves>0.98, limit of detection (LOD) was 0.90 pg/mg hair (RSP) and 1.52 pg/mg hair (9-OH-RSP), the lower limit of quantification (LLOQ) were 1.8 and 4.56 pg/mg, respectively, extraction yield were 86.9% for RSP and 86.7% for 9-OH-RSP) was successfully applied to quantify both substances in the hair of psychiatric patients treated with RSP. After washing, pulverisation, incubation in an ultrasound bath and liquid/liquid extraction of the hair samples, quantification was performed using LC/MS-MS in selected reaction monitoring mode with methaqualone as internal standard. Concentrations for RSP and its major metabolite ranged from 36 to 4765 pg/mg and from 14 to 57 pg/mg, respectively in the different hair segments. These preliminary results indicate a better relationship between the administered dose and hair concentration for 9-OH-RSP than for the parent drug. Furthermore, the RSP/9-OH-RSP ratio varied from 1 to 83.
authors: Laboratoire National de Santé, Division de Toxicologie, Université du Luxembourg, 162a, avenue de la Faïencerie, L-1511 Luxembourg, Luxembourg. serge.schneider@lns.etat.lu
authors: Serge
authors: S
authors: Schneider
authors: Estelle
authors: E
authors: Sibille
authors: Michel
authors: M
authors: Yegles
authors: Hugo
authors: H
authors: Neels
authors: Robert
authors: R
authors: Wennig
authors: Annette
authors: A
authors: Mühe
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D006197:Hair / Q000737:chemistry*; D006801:Humans; D007555:Isoxazoles / Q000032:analysis*; D008297:Male; D000068882:Paliperidone Palmitate; D011743:Pyrimidines / Q000032:analysis*; D018967:Risperidone / Q000032:analysis*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013997:Time Factors
chemical_list: D014150:Antipsychotic Agents; D007555:Isoxazoles; D011743:Pyrimidines; D018967:Risperidone; D000068882:Paliperidone Palmitate