Modified graphene oxide for micro-solid phase extraction of ciprofloxacin from seawater employing chemometrics optimization

A novel graphene oxide/ zinc oxide nano composite was synthesized and employed for simple and sensitive pipette tip based micro solid phase extraction of ciprofloxacin from seawater and human blood plasma samples following by their determination by spectrophotometry. Several parameters affecting the suggested protocol were optimized, namely type and volume of eluent, amount of sorbent, sample volume, ionic strength of sample solution, and number of cycles of extraction and elution. The optimizations were performed by both response surface methodology and one variable at a time techniques. Analytical figures of merit were achieved as: detection limit; 0.17 µg/L, linear calibration curve in the range of 1.0-200.0 µg/L; and reproducibility (as RSD%) better than 5.6. Results for the application of the technique in seawater and human blood plasma showed that this analysis method can be applied for the determination of the analyte in complex real samples such as seawater and human successfully.