Nanospray Laser-Induced Plasma Ionization Mass Spectrometry for Analysis of Trace Short-Chain Chlorinated Paraffins in Single Cells

Short-chain chlorinated paraffins (SCCPs) are a group of persistent organic pollutants that pose potential toxicity and health risks to biosystems and ecosystems. Analysis of trace SCCPs in single cells gives deeper insights into their cytotoxic, carcinogenic, and mutagenic investigations. Here a nanospray laser-induced plasma ionization mass spectrometry (nLIPI-MS) method was developed for accurate and sensitive analysis of trace SCCPs in single cells. An inner-wall molecularly imprinted polymer nanopipette was prepared, which allowed the exhaustive extraction of trace SCCPs from a single cell via molecular recognition. After extraction, the enriched SCCPs were desorbed using a methanol/chloroform (7:3, v/v) solvent. An alternating current high voltage was applied to the nanopipette to generate nanospray, and a laser beam was focused to create energetic plasma between the nanopipette and the MS inlet to ionize/secondary ionize SCCPs for mass spectrometric analysis. The method achieved fg-level detection sensitivity for the analysis of SCCPs in single cells, with limits of detection and quantitation of 0.2-0.4 and 0.6-1.0 fg/cell, respectively. Using the developed nLIPI-MS method, trace SCCPs accumulated in BEAS-2B cells following pollutant exposure were successfully detected. Significant heterogeneity in SCCP accumulation was observed among single BEAS-2B cells. Long-chain SCCPs accumulated at higher levels than short-chain SCCPs, and the cellular distribution patterns followed a gamma (γ) distribution.