2012 Annual Report
2. Detect and characterize foodborne pathogens, toxins, and bacterial threat agents with rapid optical methods.
3. Develop and evaluate detection methods for foodborne pathogens and toxins with nanotechnology.
Classification of Shiga Toxin producing Escherichia Coli (STEC) other than non-escherichia coli. O157 with hyperspectral microscope imaging: Non-O157 STEC serotypes (O26, O45, O103, O111, O121 and O145) have been recently recognized in an outbreak to cause human illness due to their toxicity. A hyperspectral microscope imaging method was developed to identify these pathogenic bacteria from the optical properties (spectral signatures) of the bacterial cells in micro-colony samples. The acousto-optic tunable filters-based hyperspectral microscope imaging method was able to identify STEC serotypes with several different classification algorithms.
Salmonella detection with Surface Enhanced Raman Spectroscopy (SERS) with silver particle encapsulated biopolymer nanosubstrate: A nano-colloidal substrate developed from silver particle encapsulated biopolymer was tested for Salmonella detection with SERS. To confirm uniformity and reproducibility of the nanosubstrates, optical properties of the substrate plasma were measured with ultra-violet, visible spectroscopy, and hyperspectral microscopy. The biopolymer nanosubstrate has a longer shelf-life and generated stable SERS signals from Salmonella and enabled the differentiation of Salmonella serotypes Typhimurium and Enteritidis.
Nanobiosensor for food toxin detection with DNA aptamers: Aptamers are single-stranded oligonucleotides generated from in vitro selection and have high affinities to their targets, which can be small molecules, proteins, virus, or cells. The protocol for detecting a single ricin protein based on these DNA aptamers was developed with a modified atomic-force microscope and the binding affinity of the aptamer to ricin was identified. The affinity was slightly higher than that with an antibody, which means aptamers could replace antibody as sensing agents. The methods will be used in further nanobiosensor development.
Sundaram, J., Park, B., Yoon, S.C., Hinton Jr, A., Windham, W.R., Lawrence, K.C. 2012. Classification and structural analysis of live and dead salmonella cells using fourier transform infrared (FT-IR) spectroscopy and principle component analysis (PCA). Journal of Agricultural and Food Chemistry. 60(4):991-1004.
Wang, B., Guo, C., Zhang, M., Park, B., Xu, B. 2012. High-resolution single-molecule recognition imaging of the molecular details of ricin-aptamer interaction. Journal of Physical Chemistry. B116(17):5316-22.
Windham, W.R., Poole, G.H., Park, B., Heitschmidt, G.W., Albano, J.P., Gottwald, T.R., Lawrence, K.C., Hawkins, S.A. 2011. Rapid screening of huanglongbing-infected citrus leaves by near infrared reflectance spectroscopy. Transactions of the ASABE. 54(6):2253-2258.
Windham, W.R., Yoon, S.C., Ladley, S.R., Heitschmidt, G.W., Lawrence, K.C., Park, B., Narang, N., William, C.C. 2012. The effect of regions of interest and spectral pre-processing on the detection of non-O157 shiga-toxin producing escherichia coli serogroups on agar media by hyperspectral imaging. Near Infrared Spectroscopy Journal. 20(5):547-558.
Yoon, S.C., Park, B., Lawrence, K.C., Windham, W.R., Heitschmidt, G.W. 2011. Line-scan hyperspectral imaging system for real-time inspection of poultry carcasses with fecal material and ingesta. Computers and Electronics in Agriculture. 79:159-168.
Yoon, S.C., Lawrence, K.C., Jones, D.R., Heitschmidt, G.W., Park, B. 2012. Motion compensated image processing and optimal parameters for egg crack detection using modified pressure. Sensing and Instrumentation for Food Quality and Safety. 5(5):172-184.
Wang, B., Guo, C., Chen, G., Park, B., Xu, B. 2012. Following aptamer-ricin specific binding by single molecule recognition and force spectroscopy measurements. ChemComm. 48:1644-1646.
Lawrence, K.C., Jones, D.R., Yoon, S.C., Heitschmidt, G.W., Anderson, K.E. 2011. Improved hairline crack detector and poor shell-quality eggs. Applied Engineering in Agriculture. 28(1):153-158.
Bowker, B.C., Fahrenholz, T.M., Sarnoski, P.J., Solomon, M.B. 2012. Alterations in the sarcoplasmic protein fraction of beef muscle with postmortem aging and hydrodynamic pressure processing. Journal of Food Science. 77(6):C594-C602.