Optimization and Improvement of Chromatographic Techniques for Bisphenol A Extraction and Characterization from Infant Bottles

Abstract

Chemicals with high manufacturing volumes, such as bisphenol A (BPA), find widespread use in thermal paper, epoxy resins, and polycarbonate plastics. However, due to its endocrine-disrupting properties, several consumer items have restricted or banned its use. As a result, BPA has been replaced by other chemical substances with similar structures in consumer goods. This study aims to enhance and validate a chromatographic method for detecting BPA in baby bottles using chemometrics tools. A Box-Behnken experimental design was employed to optimize the laboratory conditions for the maximum release of BPA through forced degradation. The study utilized three parameters as independent variables, including incubation temperature (35°C, 40°C, and 60°C), time (12 hours, 24 hours, and 36 hours), and solvent acetic acid concentration (2%, 3%, and 4%). A second-order polynomial model was proposed, and a total of 15 experiments with two replicates were conducted to determine the optimal extraction conditions. The high-performance liquid chromatography (HPLC) partitioning method was used to determine peak areas of the different extracts, serving as responses. By applying the individual desirability approach, the optimal extraction conditions were found to be a temperature of 35 °C, an extraction time of 36 hours, and an acetic acid concentration of 4% (pH = 2.72). The method was validated according to the conditions recommended by the International Conference on Harmonization (ICH) and SFSTP (Société Française des Sciences et Techniques Pharmaceutiques), ensuring high linearity, accuracy, precision, sensitivity, and robustness compared to existing liquid chromatographic methods. The improved method was applied to assess BPA levels in commercially available baby bottles, with 3 out of 7 samples testing positive for BPA, ranging from 0.615 ppb to 3.802 ppb. Notably, the enhanced method demonstrated a 12% increase in yield compared to the ISO EN 14350-2:2004 method. This study provides a reliable and effective approach for detecting BPA in baby bottles, addressing critical concerns related to consumer safety and regulatory compliance.