Analysis of benzalkonium chloride by capillary electrophoresis-tandem mass spectrometry.
Conditions for the separation and determination of benzalkonium chloride (BAC) homologues by CE with UV-detection and CE coupled to MS (IT) using electrospray as ionization source were established. The separation was performed using fused-silica capillaries of 50 microm id and 100 mM acetic acid-ammonium acetate buffer solution at pH 4.5 with 80% of ACN as carrier electrolyte. CE-MS coupling parameters were optimized and methanol-10 mM acetic acid (90:10 v/v) was selected as sheath liquid. Detection limits, based on an S/N of 3:1, were calculated, and values between 0.8 and 1.3 mg/L with CE-ESI/MS and around 0.5 mg/L with CE-ESI-MS/MS, using hydrodynamic injection (15 s, 3.5 kPa), were obtained. Good run-to-run and day-to-day precisions on concentration were achieved with RSDs lower than 8%. Quantitative analysis was carried out by the internal standard method and the calibration curves showed good linearities (r(2) > 0.98). The CE-ESI-MS/MS method was successfully applied to the analysis of BAC in different ophthalmic solutions, allowing the direct determination, identification and confirmation of the BAC homologues presented in these samples.
Para
Bianca Veronica
BV
Department of Analytical Chemistry, University of Barcelona, Spain.
Núñez
Oscar
O
Moyano
Encarnación
E
Galceran
Maria Teresa
MT
D001548:Benzalkonium Compounds / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000379:methods*; D009883:Ophthalmic Solutions / Q000032:analysis*; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D001548:Benzalkonium Compounds; D009883:Ophthalmic Solutions