Novel and selective potentiometric sensors for Cinchocaine HCl determination in its pure and Co-formulated dosage form: A comparative study of in situ carbon sensors based on different ion pairing agents

•Promising in situ carbon sensors have been fabricated for cinchocaine HCl detection.•A comparative study of the sensors based on various ion pairing agents was conducted.•The sensors achieved superior Nernstian behavior over a wide concentration range.•The sensors were applied for the CIN.HCl detection as co-formulated with other drugs.