A high-sensitivity terahertz spectroscopy technology for tetracycline hydrochloride detection using metamaterials

Antibiotic residues in animal-derived food due to their overuse in veterinary medicine will have potential adverse effects on human health. The rapid and accurate detection of these drugs is essential for ensuring human food safety. In particular, the current detection methods are usually limited by the low sensitivity or the tedious pre-treatment. Here we demonstrate that metamaterials operating at terahertz frequencies, acting as highly sensitive sensors, show promising potential for the detection of tetracycline hydrochloride (TCH). We were able to detect a trace amount of TCH, as small as 0.1 mg/L, which was about 105 times enhancement compared to the measurement of TCH on a silicon substance. Our study is likely to constitute an important step toward the detection of antibiotic residues in a food matrix.