\u201cAs you add advanced components to enhance tissue dissociation, that cumulative addition of reagents can change the final solution pH (a measure of acidity),\u201d Millet said. \u201cBut these protocols\u2014and the papers that use them\u2014don\u2019t usually report pH explicitly.\u201d<\/p>\n\n\n\n
Cells can only operate within a narrow pH range. Neurons are sensitive and work best around pH 7.4, a bit less acidic than pure water. Low brain pH (acidity) is associated with multiple neurodegenerative diseases, including Alzheimer\u2019s disease. <\/p>\n\n\n\n
In spite of these tangible consequences, Millet\u2019s team found that a common neuronal cell digestion formulation, as published, has a final solution pH of 6.6. Only three of the 50 most-cited neuronal digestion studies from the last 15 years report their final solution pH. <\/p>\n\n\n\n
\u201cpH is important in chemistry, biology, and tissue engineering, but any parameter can be overlooked in routine processes,\u201d explained Millet. \u201cWith so many off-the-shelf products available, pH can become a background assumption rather than an active variable that experimenters need to verify.\u201d<\/p>\n\n\n\n
Since Millet\u2019s interdisciplinary research program integrates the physical, chemical, and life sciences, his lab is ideally placed to set rigorous pH standards. With funding from the National Institutes of Health, Millet recruited two Engineering Vols from the Department of Biomedical Engineering (BME), Joshua Hilner and Allison Turner (both BS \u201825), to refine a reliable, easy method to monitor pH before or during cell digestion protocols.<\/p>\n\n\n\n
\u201cWith persistence, repeated experimentation, extensive literature review, and guidance from Dr. Millet, we were able to optimize the protocol and achieve reliable, reproducible results,\u201d said Turner, who is applying to medical school while working as an operating room attendant at the University of Tennessee Medical Center.<\/p>\n\n\n\n
![\"Allison](\"https:\/\/tickle.utk.edu\/bme\/wp-content\/uploads\/sites\/5\/2026\/02\/Allison-portrait-with-machine-1024x768.jpg\")