Through the direct detection of bacterial volatile organic compounds
(VOCs), via surface enhanced Raman spectroscopy (SERS), we report here a reconfigurable
assay for the identification and monitoring of bacteria. We demonstrate differentiation
between highly clinically relevant organisms: <i>Escherichia coli</i>, <i>Enterobacter
cloacae</i>, and <i>Serratia marcescens</i>.
This is the first differentiation of bacteria via SERS of bacterial VOC
signatures. The assay also detected as few as 10 CFU/ml of <i>E. coli</i> in under 12 hrs, and detected <i>E. coli</i> from whole human blood and human urine in 16 hrs at
clinically relevant concentrations of 10<sup>3</sup> CFU/ml and 10<sup>4</sup>
CFU/ml, respectively. In addition, the recent emergence of portable Raman
spectrometers uniquely allows SERS to bring VOC detection to point-of-care
settings for diagnosing bacterial infections.