Using image analysis to determine gentamicin potency by agar diffusion microbiological assay and its measurement uncertainty

Autor(es)

Saviano, Alessandro Morais ^[1] ; Lourenco, Felipe Rebello ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Ciencias Farmaceut, Dept Farm, Ave Prof Lineu Prestes, 580-Bloco 15, BR-05508000 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: MEASUREMENT; v. 146, p. 315-321, NOV 2019.
• Citações Web of Science: 0

Resumo

The inhibition zone sizes used to calculate the potency of antibiotics are often measured using calipers, which is laborious, time-consuming and provide a limited traceability audit. This work aims to propose determining potency and respective measurement uncertainty using free-based image analyzer software. Analytical conditions were optimized using design of experiments. Optimal analytical conditions were achieved using antibiotic concentrations in a range from 20 to 80 mu g mL(1), 0.3% of microbial suspension, and 5 mL of inoculated culture medium. A larger signal-to-noise ratio was obtained using images obtained from a distance of about 15 cm from the camera, using triphenyl tetrazolium solution as viability dye, with image contrast enhanced, and defined edges. The potency values obtained from inhibition zone sizes measured using image analyses and regular calipers were similar (103.4% and 104.8%); however, the measurement uncertainty obtained using the image analyses measurements was significantly reduced compared to the regular caliper (1.038 and 1.124). (C) 2019 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 16/04100-8 - Desenvolvimento de métodos microbiológicos rápidos (MMRs) para avaliação da potência de agentes antimicrobianos e suas incertezas de medição
• Beneficiário: Alessandro Morais Saviano
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 17/04539-2 - Aplicação da incerteza de medição na avaliação de desempenho de métodos analíticos
• Beneficiário: Felipe Rebello Lourenço
• Modalidade de apoio: Auxílio à Pesquisa - Regular