Tween 80 Improves the Acid-Fast Bacilli Quantification in the Magnetic Nanoparticle-Based Colorimetric Biosensing Assay (NCBA)
Cristina Gordillo-Marroquín,
Héctor J. Sánchez-Pérez,
Anaximandro Gómez-Velasco,
Miguel Martín,
Karina Guillén-Navarro,
Janeth Vázquez-Marcelín,
Adriana Gómez-Bustamante,
Letisia Jonapá-Gómez,
Evangelyn C. Alocilja
Affiliations
Cristina Gordillo-Marroquín
Health Department, El Colegio de la Frontera Sur (ECOSUR), San Cristobal de Las Casas, Chiapas 29290, Mexico
Héctor J. Sánchez-Pérez
Health Department, El Colegio de la Frontera Sur (ECOSUR), San Cristobal de Las Casas, Chiapas 29290, Mexico
Anaximandro Gómez-Velasco
The Network GRAAL (Grups de Recerca d’America i Africa Llatines), El Colegio de La Frontera Sur (ECOSUR), San Cristobal de Las Casas, Chiapas 29290, Mexico
Miguel Martín
The Network GRAAL (Grups de Recerca d’America i Africa Llatines), El Colegio de La Frontera Sur (ECOSUR), San Cristobal de Las Casas, Chiapas 29290, Mexico
Karina Guillén-Navarro
Sustainability Sciences Department, El Colegio de la Frontera Sur (ECOSUR), Tapachula, Chiapas 30700, Mexico
Janeth Vázquez-Marcelín
Mycobacteriology Laboratory, TB Prevention and Control Program for the Highlands of Chiapas, Ministry of Health of Chiapas, San Cristobal de Las Casas, Chiapas 29290, Mexico
Adriana Gómez-Bustamante
State Public Health Laboratory for Chiapas, Ministry of Health of Chiapas, Tuxtla Gutierrez, Chiapas 29040, Mexico
Letisia Jonapá-Gómez
State Public Health Laboratory for Chiapas, Ministry of Health of Chiapas, Tuxtla Gutierrez, Chiapas 29040, Mexico
Evangelyn C. Alocilja
The Network GRAAL (Grups de Recerca d’America i Africa Llatines), El Colegio de La Frontera Sur (ECOSUR), San Cristobal de Las Casas, Chiapas 29290, Mexico
Despite its reduced sensitivity, sputum smear microscopy (SSM) remains the main diagnostic test for detecting tuberculosis in many parts of the world. A new diagnostic technique, the magnetic nanoparticle-based colorimetric biosensing assay (NCBA) was optimized by evaluating different concentrations of glycan-functionalized magnetic nanoparticles (GMNP) and Tween 80 to improve the acid-fast bacilli (AFB) count. Comparative analysis was performed on 225 sputum smears: 30 with SSM, 107 with NCBA at different GMNP concentrations, and 88 with NCBA-Tween 80 at various concentrations and incubation times. AFB quantification was performed by adding the total number of AFB in all fields per smear and classified according to standard guidelines (scanty, 1+, 2+ and 3+). Smears by NCBA with low GMNP concentrations (≤1.5 mg/mL) showed higher AFB quantification compared to SSM. Cell enrichment of sputum samples by combining NCBA-GMNP, incubated with Tween 80 (5%) for three minutes, improved capture efficiency and increased AFB detection up to 445% over SSM. NCBA with Tween 80 offers the opportunity to improve TB diagnostics, mainly in paucibacillary cases. As this method provides biosafety with a simple and inexpensive methodology that obtains results in a short time, it might be considered as a point-of-care TB diagnostic method in regions where resources are limited.
