Infrared spectroscopy of plant cell cultures : noninvasive measurement of viability.

Infrared spectroscopy was used to examine suspension-cultured pear (Pyrus communis L.) and Spartina pectinata cells. Noninvasive measurements were made using internal reflectance sampling. Spectra of actively growing cells exhibited a pronounced absorbance at 2343 reciprocal centimeters. The absorbance peak was identified and verified as CO(2) dissolved in water. This peak was absent in nonviable cells. Peak height was directly proportional to percent viability in artificial mixtures of viable and nonviable cells, indicating that the level of intracellular CO(2) production could be used as a viability determinant for plant cells. Suspension-cultured cells were slowly cooled to subzero temperatures and analyzed for viability using infrared spectroscopy and tetrazolium staining. Both methods showed similar trends in viability assessment. Infrared spectroscopy could provide a more detailed understanding of cell viability and allow measurement on a noninvasive basis.