Effect of sample thickness on the extracted near-infrared bulk optical properties of Bacillus subtilis in liquid culture

Dzhongova, Elitsa and Harwood, Colin R. and Thennadil, Suresh (2011) Effect of sample thickness on the extracted near-infrared bulk optical properties of Bacillus subtilis in liquid culture. Applied Spectroscopy, 65 (11). pp. 1223-1324. ISSN 0003-7028 (https://doi.org/10.1366/11-06338)

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Abstract

In order to determine the bulk optical properties of a Bacillus subtilis culture during growth phase we investigated the effect of sample thickness on measurements taken with different measurement configurations, namely total diffuse reflectance and total diffuse transmittance. The bulk optical properties were extracted by inverting the measurements using the radiative transfer theory. While the relationship between reflectance and biomass changes with sample thickness and the intensity (absorbance) levels vary significantly for both reflectance and transmittance measurements, the extracted optical properties show consistent behavior both in terms of the relationship with biomass and magnitude. This observation indicates the potential of bulk optical properties for building models that could be more easily transferable compared to those built using raw measurements.