Construction of novel potentiometric sensors modified with biogenically synthesized metal oxide nanoparticles for sensitive detection of the opioid agonist-antagonist nalbuphine hydrochloride in its injection

Novel and sensitive potentiometric sensors were described for the assay of nalbuphine HCl (NBP) in authentic powder and injection samples. The developed sensors were modified with alumina nanoparticles (Al(2)O(3)NPs) and copper oxide nanoparticles (CuONPs). The nanoscale materials were synthesized using the extract of Salvia officinalis leaves in an environmentally friendly manner. The synthesized metal oxides were fully confirmed by various analytical techniques. Scanning electron microscope confirmed the morphology of nanosized materials with even distribution and particle size of 55.07 ± 4.15 and 59.48 ± 4.50 nm for Al(2)O(3)NPs and CuONPs, respectively. The modified sensors were prepared in three different steps. Nalbuphine hydrochloride was mixed with phosphomolybdic acid to prepare the sensor material nalbuphine phosphomolybdate (NBP-PM). It was then mixed with polyvinyl chloride in the presence of o-nitrophenyl ether and metal oxide nanoparticles to form the membrane matrix. Finally, a copper wire was coated with the sensing material. Excellent potentials of 1.0 × 10(−8)-1.0 × 10(−2) and 1.0 × 10(−9)-1.0 × 10(−2) mol L(−1) were measured with lower assay limits of 4.8 × 10(−9) and 5.0 × 10(−10) mol L(−1). The average detection % were 99.28 ± 0.58% and 99.52 ± 0.28% for NBP-PM-Al(2)O(3)NPs and NBP-PM-CuONPs, correspondingly. The suitability of the described sensors was investigated in terms of various validation criteria, and the modified sensors exposed excellent applicability and insurance for the quantification of nalbuphine hydrochloride in its bulk samples and injections compared with another standard sensor. It is obvious that the developed NBP-PM-Al(2)O(3)NPs and NBP-PM-CuONPs will serve as suitable sensors for the determination of NBP.