title: Rapid, in situ detection of cocaine residues based on paper spray ionization coupled with ion mobility spectrometry.
abstract: In this paper, a novel approach based on paper spray ionization coupled with ion mobility spectrometry (PSI-IMS) was developed for rapid, in situ detection of cocaine residues in liquid samples and on various surfaces (e.g. glass, marble, skin, wood, fingernails), without tedious sample pretreatment. The obvious advantages of PSI are its low cost, easy operation and simple configuration without using nebulizing gas or discharge gas. Compared with mass spectrometry, ion mobility spectrometry (IMS) takes advantage of its low cost, easy operation, and simple configuration without requiring a vacuum system. Therefore, IMS is a more congruous detection method for PSI in the case of rapid, in situ analysis. For the analysis of cocaine residues in liquid samples, dynamic responses from 5 μg mL(-1) to 200 μg mL(-1) with a linear coefficient (R(2)) of 0.992 were obtained. In this case, the limit of detection (LOD) was calculated to be 2 μg mL(-1) as signal to noise (S/N) was 3 with a relative standard deviation (RSD) of 6.5% for 11 measurements (n = 11). Cocaine residues on various surfaces such as metal, glass, marble, wood, skin, and fingernails were also directly analyzed before wiping the surfaces with a piece of paper. The LOD was calculated to be as low as 5 ng (S/N = 3, RSD = 6.3%, n = 11). This demonstrates the capability of the PSI-IMS method for direct detection of cocaine residues at scenes of cocaine administration. Our results show that PSI-IMS is a simple, sensitive, rapid and economical method for in situ detection of this illicit drug, which could help governments to combat drug abuse.
authors.affiliation: Division of Chemical Metrology & Analytical Science, National Institute of Metrology, Beijing, 100013, P. R. China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Jingjing
authors.initials: J
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Jiang
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Qiao
mesh_terms: D003042:Cocaine / Q000032:analysis*; D013287:Illicit Drugs / Q000032:analysis*; D057230:Limit of Detection; D016014:Linear Models; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods; D015813:Substance Abuse Detection / Q000295:instrumentation / Q000379:methods; D013499:Surface Properties; D013997:Time Factors
chemical_list: D013287:Illicit Drugs; D012996:Solutions; D012997:Solvents; D003042:Cocaine