As Applications Chemists in the LC lab, one of the most exciting parts of our jobs is the variety of analyses we are exposed to. One day you are developing a method for potency analysis in cannabis samples, the next you are looking at anti-epileptic drugs in urine. We’re regularly challenged to think outside the box to provide the best solutions for our customers.
In some recent work, my colleague, Shun-Hsin Liang, was tasked to develop a method for nicotine and related compounds in urine using LC-MS/MS. The challenge was finding suitable analytical conditions for a rapid, accurate, and reproducible method geared toward high-throughput testing laboratories. Typically, this analysis uses high-pH chromatography with relatively high concentrations of additives to increase retention, improve peak shape, and reduce peak tailing. These conditions may lead to some additional non-routine maintenance (like changing pump seals and replacing tubing), and if you’re in a high-throughput laboratory, you know non-routine maintenance events always pop up at the most inopportune time.
Shun-Hsin was able to use the Raptor Biphenyl column and standard, low pH, reversed-phase LC-MS mobile phases that are compatible with a variety of LC-MS instrumentation. The method provided excellent performance for the simultaneous analysis of nicotine, two major metabolites (cotinine and trans-3’-hydroxycotinine), two minor metabolites (nornicotine and norcotinine), and a minor tobacco alkaloid, anabasine, in human urine. Accurate and reproducible analysis was achieved in less than 5 minutes of chromatographic analysis time, making the column and method well suited to low-cost, high-throughput analysis of nicotine-related compounds.
