ABSTRACT
OBJECTIVE: To establish an HPLC assay to determine the uptake characteristics of bencycloquidium bromide (BCQB) in Calu-3 cells. METHODS: The samples were analyzed with a Discovery C18 column (4.6 mm×250 mm, 5μm) at 25°C. The mobile phase was acetonitrile-water containing 0.27% KH2PO4 and 0.3% triethylamine (pH adjusted to 3.0 with H3PO4) (35:65). The flow rate was 1.0 mL·min-1. The concentrations of BCQB in Calu-3 cells at various time were measured. RESULTS: The linearity of BCQB calibration curve was good in the range of 0.0102-1.0220 μg·mL-1 (r=0.9998). The minimal quantitation limit was 0.0102 μg·mL-1. The uptake of BCQB increased rapidly during the first 30 min. When the concentration of BCQB increased from 20 to 500 μmol·L-1, the uptake increased almost linearly. However, the curve showed saturation when the concentration of BCQB reached 500 μmol·L-1. CONCLUSION: This assay is rapid, sensitive and specific, and can be applied to determine BCQB concentrations in Calu-3 cells. BCQB can be uptaken by Calu-3 cells rapidly, and the uptake shows saturation with increase of dosage.