@article{Cruz_Nascimento_Teixeira_Oliveira_Lopes_2018, place={Viçosa/MG, BR}, title={DEVELOPMENT OF A METHOD FOR THE DETERMINATION OF AMOXICILLIN IN CAPSULES BY POTENTIOMETRIC TITRATION}, volume={4}, url={https://periodicos.ufv.br/jcec/article/view/2490}, DOI={10.18540/jcecvl4iss2pp0234-0239}, abstractNote={<p><em>This work presents the determination of amoxicillin (H<sub>3</sub>Amox<sup>+</sup>) in capsules by potentiometric titration. An optimized method was done with a standard amoxicillin solution that was title with NaOH solution. The initial pH was 4.35. As expected, the first equivalence point was not observed, because the fraction of H<sub>3</sub>Amox<sup>+</sup> was about 2.4%. Thus, HCl solution was added to the system to protonate the zwitterion H<sub>2</sub>Amox</em><em><sup>±</sup></em><em> (98%), and then visualize the first equivalence point. Two inflections were observed, the first one of the neutralization of H<sub>3</sub>Amox<sup>+</sup> e HCl and the second one of the neutralization of the zwitterion. The equivalent volumes were estimated using the first derivative method, and the volume variation (</em><em>D</em><em>V) between the equivalent volumes was used to determine the amoxicillin. The results showed 99% of accuracy and coefficient of variation of 7.2%.</em></p>}, number={2}, journal={The Journal of Engineering and Exact Sciences}, author={Cruz, Jean Castro and Nascimento, Mayra Aparecida and Teixeira, Aline Maria and Oliveira, André Fernando and Lopes, Renata Pereira}, year={2018}, month={jul.}, pages={0234–0239} }