Rapid analysis of abused drugs using nanostructured silicon surface assisted laser desorption/ionization mass spectrometry

• Published in: Analyst (London) Vol. 137; no. 3; pp. 654 - 661
• Main Authors: Cheng, Yu-Che, Chen, Kun-Han, Wang, Juo-Shin, Hsu, Wen-Liu, Chien, Chih-Cheng, Chen, Wen-Yih, Tsao, Chia-Wen
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 07.02.2012
• Subjects: Amphetamine - urine; Analytical chemistry; Chemistry; Chips; Chromatographic methods and physical methods associated with chromatography; Codeine - urine; Crack opening displacement; Drugs; Exact sciences and technology; Gas chromatographic methods; Gas Chromatography-Mass Spectrometry; Ionization; Ketamine - urine; Lasers; Limit of Detection; Methamphetamine - urine; Microscopy, Electron, Scanning; Morphine - urine; Nanostructure; Nanostructures; Reproducibility of Results; Silicon; Silicon - chemistry; Spectrometric and optical methods; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Street Drugs - urine; Urine; Performance evaluation; Chemical analysis; Morphine; Metal; Laser desorption; Target; Specificity; Standard test; Detection limit; Amfetamine; Peak; Silicon; Quantitative analysis; Drug; Urine; Antibody; Sample; Use; Gas chromatography; Repeatability; Sensitivity; Ketamine; Ionization; Volume; Linearity; Matrix method; Mass spectrometry
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/c1an15913e

This study developed a rapid, sensitive, and matrix-free method for the determination of amphetamine (AMP), methamphetamine (MA), codeine (COD), morphine (MOR), and ketamine (KET) using nanostructured silicon surface assisted laser desorption/ionization mass spectrometry (nSi-MS). The nanostructured silicon (nSi) chip used in this study was created by employing the metal-assisted etching process. Drug standard tests were applied to the nSi chip platform to evaluate the nSi-MS performance, including detection sensitivity, limit of detection, linearity, and repeatability. Real urine samples obtained from drug addict detainees were directly applied to the nSi chip for drug analysis. By observing the nSi-MS spectra, the target drug peaks can be identified; and an antibody pull-down assay was performed to confirm the specificity of the detected targets. nSi-MS drug quantification was assayed, yielding comparable results with those from using the GC-MS approach. The advantages of applying nSi-MS to analyze AMP, MA, COD, MOR, and KET in the urine of addicts are simple, extremely small urine volumes (10 L), and a fast analysis procedure (<15 minutes). This study developed a rapid, sensitive, and matrix-free method for the determination of abused drugs using nSi-MS method. Drug standards, real urine samples, antibody pull-down assay and nSi-MS drug quantification experiments were performed to evaluate the nSi-MS performance.