Brompheniramine as a novel probe for indirect UV detection and its application for the capillary electrophoresis of adamantane drugs

Abstract

Brompheniramine, an antihistamine drug, was employed as a novel UV probe for capillary electrophoresis with indirect UV detection of adamantane drugs (memantine, amantadine, and rimantadine). The probe possesses high molar absorptivity of 24 × 10 L/mol cm at 6 mM, which enables the measurement of these nonchromophore analytes without derivatization. The simple background electrolyte (10 mM sodium dihydrogen phosphate (pH 5.0) containing 5 mM brompheniramine and 6 mM β-cyclodextrin) provided the separation of the analytes in a short time (7.5 min). Under these conditions, brompheniramine had similar mobility to that of the analyte ions resulting in symmetric peaks with minimal electrodispersion. The analytes displace the probe at a one-to-one ratio with transfer values close to unity. β-Cyclodextrin played a role in the resolution of the structurally similar adamantane derivatives. Method validation showed good linearity (r > 0.98), precision (%RSD ≤ 3.30), and accuracy (recoveries ranging from 98 to 109%). The proposed method was successfully applied to determine the adamantane content in pharmaceutical products.

In‐capillary derivatization with fluorescamine for the rapid determination of adamantane drugs by capillary electrophoresis with UV detection

“…The method was fully validated showing excellent analytical parameters in terms of linearity, accuracy, precision, and sensitivity. The results are comparable with our previous report in terms of the simple CE conditions (borate vs. phosphate buffer), analysis time (about 7 min), resolution (2.4) and validation data. Nevertheless, the current method provides a better LOD (up to six‐times lower) and higher S/N ratios (three‐times enhancement) in comparison with CE‐indirect UV method .…”

“…The results are comparable with our previous report in terms of the simple CE conditions (borate vs. phosphate buffer), analysis time (about 7 min), resolution (2.4) and validation data. Nevertheless, the current method provides a better LOD (up to six‐times lower) and higher S/N ratios (three‐times enhancement) in comparison with CE‐indirect UV method . Since FC was used as the derivatization reagent, the sensitivity enhancement factor could be greater, providing that the CE is coupled with a fluorescence detector.…”

“…The analysis time of 7 min is similar to that of the CE‐indirect UV detection, which required about 7.5 min. Precision of the proposed method shows lower %RSDs than those of CE with indirect UV detection and GC–MS methods. Moreover, the proposed method offers a better sensitivity in terms of the lower LOD and LOQ than most methods indicating that the in‐capillary derivatization could improve the detectability in CE–UV.…”

“…The derivatization procedures and CE conditions were optimized and the method was validated in comparison with reported methods. The proposed method provided comparable validation data with the other methods and could be applied to quantify the admantane drugs in pharmaceutical formulations. The method is convenient and does not require additional instruments since the derivatization could be automatically done in the capillary.…”

“…Generally, validation data of the current method is in good agreement with the reported methods ( Table 2). The analysis time of 7 min is similar to that of the CE-indirect UV detection, which required [18] and GC-MS [10] methods. Moreover, the proposed method offers a better sensitivity in terms of the lower LOD and LOQ than most methods indicating that the in-capillary derivatization could improve the detectability in CE-UV.…”