Showing posts with label
detection of antibiotic residues.
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Showing posts with label
detection of antibiotic residues.
Show all posts
Lijuan Xie,
Weilu Gao,
Jie Shu,
Yibin Ying
& Junichiro Kono
http://www.nature.com/srep/2015/150302/srep08671/full/srep08671.html?WT.ec_id=SREP-639-20150303
We have detected trace amounts of molecules of antibiotics (kanamycin sulfate) dispersed on metasurfaces with terahertz (THz) spectroscopy. Utilizing the extraordinary optical transmission resonance of an array of square-shaped slits on a silicon substrate at ~0.3 THz, we were able to monitor varying concentrations of kanamycin sulfate as low as ~100 picogram/L. In contrast, the lowest detectable concentration of kanamycin sulfate on silicon without any metallic structure was ~1 gram/L. This dramatic ~1010 times enhancement of sensitivity is due to the near-field enhancement of THz electric fields by the metamaterial structure. This result thus demonstrates the power and usefulness of metamaterial-assisted THz spectroscopy in trace molecular detection for biological and chemical sensing as well as for food product quality and safety inspection and control.
MY NOTE- THIS IS REALLY INTERESTING AND DEMONSTRATES YET ANOTHER PRACTICAL USE FOR THz.
http://pubs.rsc.org/en/Content/ArticleLanding/2011/AN/C0AN01016B
We report the use of terahertz (THz) spectroscopy to explore the spectral properties of eleven antibiotics commonly used in livestock production. Eight of the eleven antibiotics showed specific fingerprints in the frequency range between 0.1 and 2 THz. The main spectral features of two antibiotics (doxycycline and sulfapyridine) were still detectable when they were mixed with three food matrices (feed, milk, and egg powder). These preliminary results indicate that THz spectroscopy could be suitable for screening applications to detect the presence of antibiotic residues in the food industry, with the prospect to allow inspections directly on the production lines. THz spectroscopy is a non-destructive, non-contact, and real-time technique that requires very little sample preparation. Moreover, THz radiation can penetrate plastic and paper, which enables the detection of antibiotics in packaged food.
