Quadruple isotope dilution gas chromatography-mass spectrometry after simultaneous derivatization and spraying based fine droplet formation liquid phase microextraction method for the accurate and sensitive quantification of chloroquine phosphate in human serum, urine and saliva samples at trace levels

• Published in: Journal of Chromatography A 2021-08, Vol.1651, p.462273, Article 462273
• Main Authors: Erarpat, Sezin, Bodur, Süleyman, Öner, Miray, Günkara, Ömer Tahir, Bakırdere, Sezgin
• Format: Article
• Language: English
• Subjects: Chloroquine phosphate; Gas chromatography mass spectrometry; Liquid phase microextraction; Quadruple isotope dilution
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2021.462273

•Chloroquine phosphate was simultaneously derivatized and extracted by SD-SFDF-LPME.•Chloroquine acetamide-d3 was firstly synthesized and used as isotopic analogue.•Quadruple isotope dilution (ID4) was combined to SD-SFDF-LPME method.•The accuracy and precision of the SD-SFDF-LPME method were improved via ID4.•High recoveries with low standard deviation were achieved for biofluid samples. This study presents an accurate and precise analytical strategy for the determination of chloroquine phosphate at trace levels in human body fluids (urine, serum, and saliva). Simultaneous derivatization-spraying based fine droplet formation-liquid phase microextraction (SD-SFDF-LPME) method was used to derivatize and preconcentrate the analyte prior to gas chromatography-mass spectrometry (GC–MS) measurements. Acetic anhydride was employed as derivatizing agent in this study. After optimizing the SD-SFDF-LPME method, the limit of detection (LOD) and limit of quantitation (LOQ) were found to be 0.16 and 0.53 mg/kg, respectively. Quadruple isotope dilution (ID4) was coupled to the SD-SFDF-LPME method in order to alleviate matrix effects and promote accuracy/precision of the method. Chloroquine acetamide-d3 was firstly synthesized in our research laboratory and used as the isotopic analogue of the analyte in the ID4 experiments. Superior percent recovery results (99.4% – 101.0%) with low standard deviation values were obtained for the spiked samples. This validated the developed SD-SFDF-LPME-ID4-GC–MS method as highly accurate and precise for the determination of chloroquine phosphate at trace levels. In addition, the isotopic analogue of the analyte was obtained via the acetamide derivative of the analyte, which is an alternative to obtain isotopic analogues of organic compounds that are not accessible or commercially available.