Rigor & Reproducibility: pH Adjustments of Papain with L-Cysteine Dissociation Solutions and Cell Media Using Phenol...

Area of Science:

• Biochemistry
• Cell Biology
• Biomedical Engineering

Background:

• Phenol red is a cost-effective pH indicator used in various assays.
• Real-time monitoring of extracellular pH changes reflects cellular metabolic activity.
• Standard tissue digestion protocols often neglect critical parameters like pH control.

Purpose of the Study:

• To present a spectrophotometric method for monitoring and adjusting pH in low-volume enzymatic dissociation media.
• To validate the method's reliability against traditional pH probes.
• To emphasize the importance of pH control for cell viability in tissue dissociation.

Main Methods:

• Utilized phenol red as a colorimetric pH indicator in a plate reader.
• Titrated dissociation media to a physiological pH of ~7.4.
• Validated spectrophotometric pH measurements with conventional glass pH probes.

Main Results:

• Demonstrated a reliable spectrophotometric method for pH assessment in 1 mL dissociation media.
• Confirmed that unadjusted papain-based media with L-cysteine can be acidic (pH 6.6), impacting cell viability.
• Showcased the method's ability to ensure accurate pH for cell isolation.

Conclusions:

• The developed method enhances reproducibility in cell dissociation by enabling pH documentation.
• Accurate pH control is crucial for isolating viable primary cells for tissue engineering, single-cell omics, and neurophysiological assays.
• This accessible approach improves consistency in biomedical and cellular research.