Desarrollo de formulaciones locales de tampón de carga y marcador de peso molecular de 100 pb para electroforesis en gel de agarosa

Abstract

Irregular access to molecular biology reagents limits genetic research in Latin America due to high importation costs, dependence on international suppliers, and regulatory constraints that hinder scientific continuity in resource-limited settings. Natural pigments, including anthocyanins, betalains, chlorophylls, curcumin, capsanthin, and norbixin, as well as food-grade synthetic dyes, were evaluated through electrophoretic screening. Loading buffer formulations were prepared by combining two base buffer systems (60 mM Tris-HCl, pH 7.6, and 6X TE buffer) with different dye concentrations. Chemical stability was monitored by UV–Vis spectrophotometry over 120 days under three storage conditions. The molecular weight marker was generated from PCR products amplified from the rpoB gene of E. coli. The results showed that Brilliant Blue FCF (E133) and Tartrazine (E102) were colorants that showed compatibility with electrophoretic conditions. The T7 formulation, consisting of Tris-HCl without EDTA and a high concentration of both dyes, stored at 20 Celcius degree, exhibited the highest spectral and electrophoretic stability throughout the evaluation period. The developed molecular marker produced a reproducible banding pattern ranging from 400 to 2000 bp, with performance comparable to that of commercial references. These findings demonstrate that the local production of functional electrophoretic reagents is technically feasible using accessible and low-cost materials. This study provides a reproducible in-house methodology for the generation of electrophoresis reagents, with the potential to reduce the technological gap in laboratories located in low- and middle-income countries.