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Updated: Jul 17, 2025

Enhanced Reproducibility and Precision of High-Throughput Quantification of Bacterial Growth Data Using a Microplate Reader
Published on: July 27, 2022
A high-throughput protocol for measuring solution pH of bacterial cultures using UV-Vis absorption spectrophotometry
Kristen A Engevik1, Hyland Gonzalez2, Clay Daniels2
1Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
Abstract:
We present a protocol for measuring the pH of cell-free bacterial-conditioned media based on changes in the ultraviolet-visible (UV-Vis) absorbance spectrum using the pH indicator dye litmus. This protocol includes detailed procedures for performing bacterial culturing, examining bacterial growth, collecting cell-free supernatant, litmus dye addition, and pH-based calibration curve preparations. This assay has been designed for flexible formatting that can accommodate both high-volume and low-volume sample sets.
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