Antibody Immobilization on Magnetic Nanoparticles Coupled with MALDI-MS for the Analysis of Methamphetamine and Amphetamine in Urine

• Main Authors: Kun-Ru Wu, 吳坤儒
• Other Authors: He-Hsuan Hsiao
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/34290591074340057424

碩士 === 國立中興大學 === 化學系所 === 103 === In this study, antibody decorated magnetic nanoparticles were employed to analyze methamphetamine and amphetamine in urine by using matrix assisted laser desorption ionization time of flight mass spectrometer (MALDI-TOF). The magnetic nanoparticles were synthesized by co-precipitation method and subsequently modified vinyl group (C=C) with the silane reaction. The boronic acid functionalized magnetic nanoparticles were prepared through free-radical addition reaction with vinyl group. Afterwards, the boronic acid decorated magnetic nanoparticles were conjugated with antibody for the selective extraction of the methamphetamine and amphetamine. The analytes were eluted under a high percentage of organic matrix solution. The optimized conditions for the extraction of analytes with antibody immobilization on magnetic nanoparticles were evaluated including, diluted factor, the ratio of organic solvent in matrix solution¬, extraction time and eluting time. Due to the selectivity of antibody, the urine sample did not need any further pretreatment to reduce matrix effect. The MALDI matrix dissolved in 85% ACN was used for eluting solution and could be directly spotted on the MALDI target plate for the following MS　analysis. The extraction time was 10 minutes and the eluting time was 10 and 15 minutes for amphetamine and methamphetamine, respectively. The linear range for both analytes was 25 – 1000 ng/mL in the urine. The limit of detection were 1.87 ng/mL and 3.75 for amphetamine and methamphetamine, respectively. The method was applied to the addicts’ urine. The concentration of amphetamine and methamphetamine in the three addicts’ urine were 276 and 674 ng/mL; 163 and 634 ng/mL and 131 and 626 ng/mL, respectively, which were consistent with GC/MS results. In brief, as compared to high false-positive rate of enzyme-linked immunosorbent assay (ELISA) and time consuming LC-MS analysis, we developed an easy, rapid and low false-positive rate method for the qualification and quantification of abused drug by using boronic acid decorated magnetic nanoparticles coupling with MALDI MS analysis.