A validation method development for simultaneous LC-ESI-TOF/MS analysis of some pharmaceuticals in Tangkas river-Malaysia

• Autor(a) principal: Al-Qaim,Fouad F.
• Data de Publicação: 2014
• Outros Autores: Abdullah,Md P., Othman,Mohamed R., Latip,Jalifah, Afiq,Wan
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532014000200010
• topic: basic pharmaceuticals; LC-ESI-TOF/MS; solid phase extraction; extraction efficiency; Tangkas river

Pharmaceuticals are synthetic or natural chemicals that can be found in prescription medicines, over-the-counter therapeutic drugs and veterinary drugs. The occurrence of pharmaceuticals in the environment and the water cycle at trace levels (in the range of nanograms to low micrograms per litre) has been widely discussed and published in literature in the past decade. The increase in detection is largely attributable to the advances in analytical techniques and instrumentation. This paper describes development, optimisation and validation of a method for the simultaneous analysis of 7 multi-class pharmaceuticals (caffeine (CAF), Prazosin (PRZ), enalapril maleate (ENL), carbamazepine (CBZ), nifedipine (NFD), levonorgestrel (LNG), simvastatin (SMV)) using solid phase extraction (SPE cartridges Oasis HLB) followed by liquid chromatography-time-of-flight/mass spectrometry (LC-ESI-TOF/MS). Its linearity, 0.5-250 µg L-1, provided determination coefficients (R²) above 0.99 for all compounds. The Instrumental Quantification Limits (IQLs) for all pharmaceuticals ranged from 0.5-5 µg L-1 in the solvent as a standard mixture (i.e., direct injection). The extraction efficiency (EE%) was more than 40% and 60% in river and deionised water for most of compounds, respectively. Limit of quantification (LOQ) for all pharmaceutic als ranged from 13-800 ng L-1 in spiked river water. The inter and intra day precision of the method, calculated as the relative standard deviation (RSD%), 2.33-22.3% and 0.6-9.9%, respectively, except for caffeine, which has a RSD% of 20.1% at 50 µg L-1. Matrix effect was investigated and ranged from 10-41%. Out of seven pharmaceuticals, six pharmaceutical compounds were detected in the river water sample.