Design and Validation of a Green CPSE‐LC–MS/MS Method for Detection of Zopiclone in Biological Samples

ABSTRACT Zopiclone is a cyclopyrrolone derivative and the first developed Z‐hypnotic drug widely prescribed for the short‐term management of insomnia. But due to its strong sedative and amnesic properties, it is often used as a date rape drug in drug‐ facilitated sexual assaults (DFSA). Thus, a simple and sensitive detection method based on cellulose paper sorptive extraction (CPSE) coupled with LC‐MS/MS for zopiclone in blood and urine has been established. Under the optimum extraction conditions, a linear relationship was achieved in the range of 1.32–1000 ng/mL with the correlation coefficient (r 2 ) of 0.9987 for biological samples. The LOD was established to be 0.122 ng/mL and LOQ 0.407 ng/mL. The relative recovery greater than 90% was obtained from spiked samples of blood and urine. The relative standard deviation (RSD) was less than 6.136%. The combination of CPSE with LC‐MS/MS offers an alternative analytical approach for the detection of zopiclone in biological samples. The developed method was further evaluated for its environmental and practical sustainability using the greenness metric approach, BAGI (Blue Applicability Grade Index). The results confirmed that the method not only met analytical performance requirements but also demonstrated eco‐friendliness and high practical applicability. This dual evaluation highlights the method's suitability for routine laboratory use in forensic investigations.