Two analytical approaches for determination of amprolium and triclabendazole targeting their tertiary amino groups in waste water

Abstract This study has been proposed new, sensitive, straightforward, and validated spectrophotometric and spectrofluorimetric methods for estimating of amprolium (AMP) and triclabendazole (TCB) in laboratory prepared pharmaceutical wastewater. Both methods were based on the reaction of AMP and TCB with Eosin-Y in acidic medium, targeting the tertiary amino groups of the concerned analytes, generating an orange-red ion pair complexes. The resulting products were measured by spectrophotometric (Method I) and spectrofluorimetric (Method II) tools. Regarding method I, the absorbance was measured at 547 nm with a lower detection limit of 45 ng/mL and quantitation limit of 136 ng/mL for AMP with corresponding values of 191 ng/mL and 579 ng/mL for TCB. The proposed method exhibited a linear pattern over the concentration range of 100–5000 and 1500–10,000 ng/mL for amprolium and triclabendazole, respectively. Meanwhile in method II, the produced complex was measured at λem 552 nm for AMP or 555 nm for TCB after excitation at λex 470 nm with a lower detection limit of 142 ng/mL and quantitation limit of 429 ng/mL for AMP with corresponding values of 67 ng/mL and 202 ng/mL for TCB. The proposed method exhibited a linear pattern over the concentration range with linearity ranges of 500–2000 and 100–1500 ng/mL for amprolium and triclabendazole, respectively. The International Conference on Harmonization (ICH) requirements for linearity, accuracy, precision, specificity, and robustness were followed in the comprehensive validation of the proposed methods, allowing its application successfully to determine the studied analytes in wastewater samples.