Infrared microspectroscopy of individual human cervical cancer (HeLa) cells suspended in growth medium

We report for the first time the infrared spectra of individual human cervical cancer (HeLa) cells suspended in buffer or cell culture medium. Although we did not establish whether these cells were viable at the time of spectral data acquisition, we believe that the methodology used is applicable to the study of live cells. Data were collected either from entire cells, using 25- to 40-(mu)m apertures, or via an imaging approach, where pixels measuring 6.25 × 6.25 (mu)m were assembled to form a map of a cell in suspension. Measurements were carried out both in reflection/absorption and in transmission modes. The results reported here might have farreaching implications for the use of infrared microspectroscopy to monitor cell proliferation, drug response, and other cell biological parameters in live cells.