Journal of Chromatography A, 1216 (2009) 824–829 Contents lists available at ScienceDirect Journal of Chromatography A journal homepage: www.elsevier.com/locate/chroma Analysis of quinocide in unprocessed primaquine diphosphate and primaquine diphosphate tablets using gas chromatography–mass spectrometry with supersonic molecular beams Ilia Brondz a,∗ , Alexander B. Fialkov b , Aviv Amirav b a Department of Biology, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway b School of Chemistry, Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel article info Article history: Received 12 September 2008 Received in revised form 11 November 2008 Accepted 17 November 2008 Available online 21 November 2008 Keywords: GC–MS Supersonic molecular beam Supersonic GC–MS Primaquine Quinocide Isomer analysis Anti-malaria drug Contaminations in primaquine tablets abstract Malaria is one of the most widespread and deadly diseases on the planet. Every year, about 500 million new cases are diagnosed, and the annual death toll is about 3 million. Primaquine has strong antiparasitic effects against gametocytes and can therefore prevent the spread of the parasite from treated patients to mosquitoes. It is also used in radical cures and prevents relapse. Consequently, primaquine is an often-used drug. In this study the separation of unprocessed primaquine from the contaminant quinocide based on gas chromatography–mass spectrometry with supersonic molecular beam (SMB) is presented and 7.5 mg primaquine diphosphate tablets were analyzed. We present a novel method for fast determination of quinocide which is an isomer of primaquine as the main contaminant in unprocessed primaquine and in its medical form as tablets by gas chromatography–mass spectrometry with SMB (also named supersonic GC–MS). Supersonic GC–MS provides enhanced molecular ion without any ion source related peak tailing plus extended range of compounds amenable for GC–MS analysis. In addition, major isomer mass spectral effects were revealed in the mass spectra of primaquine and quinocide which facilitated the unambiguous identification of quinocide in primaquine tablets. Fast GC–MS analysis is demonstrated with less then 2 min elution time of the drug and its main contaminants. Crown Copyright © 2008 Published by Elsevier B.V. All rights reserved. 1. Introduction Malaria is one of the most widely spread and deadly diseases on the planet. Primaquine has high antiparasitic effects against game- tocytes and thus the ability to prevent the spread of the parasite from patients under treatment to mosquitoes. It is also used in rad- ical cures and prevents relapses. Consequently, primaquine is an often-used drug. It has recently been shown that unprocessed primaquine (CAS 90-34-6) used in the pharmaceutical industry is contaminated with the positional isomer quinocide (CAS 525-611) [1–9]. Currently, the Pharmacopoeia [10] allows primaquine purity from 98.5% to 101.5%. Quinocide is a principal contaminant in the drug primaquine diphosphate. Quinocide is also a highly toxic substance. The tox- icological properties of quinocide and the tolerances of animals to the drug, and the metabolism are presented in [11–14]. The acute toxic effects of combinations of quinocide with other anti- ∗ Corresponding author. Tel.: +47 22 85 73 53. E-mail addresses: ilia.brondz@bio.uio.no (I. Brondz), fialkov@tau.ac.il (A.B. Fialkov), amirav@tau.ac.il (A. Amirav). malarial drugs were presented in [15]. The conclusion was that quinocide caused either additive or synergistic toxic effects and similar observations were seen using a unicellular model [3]. Pri- maquine and quinocide can have a number of side effects, such as inducing methemoglobinemia, effects on the red blood cell membrane, haemolytic effects [16]. The neurotoxicity of the 8- aminoquinolines is well known. Polyamines may be involved in the development of hepatic encephalopathy and cerebral oedema. Neuropsychiatric manifestations after therapy with the quino- lines derivative mefloquine were reported [16]. Cardio toxicity in patients undergoing malaria therapy with aminoquinolines due to blockade of Na + channels is discussed and cases showing the carcinogenicity of primaquine have also been described [16]. The nature of contaminants in this drug does not require a descrip- tion [10], despite the high level of contamination allowed. In 2004 [2], evidence of the nature of the contaminant in primaquine diphosphate was presented by using GC–MS. Since presentation at international meetings in 2004 [2] and a paper published in 2005 [4], very little has been done to develop GC–MS analyti- cal procedures for the analysis of primaquine in its medical form as tablets for the presence of thermally labile substances such as quinocide. Quinocide is less thermally stable than primaquine. Con- 0021-9673/$ – see front matter. Crown Copyright © 2008 Published by Elsevier B.V. All rights reserved. doi:10.1016/j.chroma.2008.11.043