Fang-hui Wu,Guo-qiang Wen,Xiang-rui Luo,Xu-dong Xu,Zi Liu,Wen-bin Sun,Yan-shang Kang,Zhengquan Yan
To improve the sensitivity for electro-chemiluminescent (ECL) detection of chloramphenicol (CAP), a common broad-spectrum antibiotic, boron nitride quantum dots (BNQDs) were prepared with excellent photoelectric property and low toxicity. After its structure and electrochemical property were investigated in detail, it was noted that the ECL signal of Ru(Phen)32+ could be strengthened by the proposed BNQDs, which was further activated by ten's times in the presence of CAP. Under the optimized conditions, there was an excellent linear relationship between ΔECL and lgcCAP in a wide linear range from 1.0 × 10−10 to 1.0 × 10−6 mol l−1 CAP. The detection limit was super-low to be 3.3 × 10−11 mol l−1 (S/N = 3). When applied for CAP detection in real pharmaceutical and food samples, the recoveries were between 97.8% and 105.7% with R.S.D. less than 3.3%. A possible CAP-activated ECL mechanism of BNQDs-Ru(phen)32+ was also proposed. This work will offer a great potential for efficient monitoring of CAP pollution and clinical diagnosing of CAP-related diseases in future.
Huifang Zhang,Fang Luo,Peilong Wang,Longhua Guo,Bin Qiu,Zhenyu Lin
A simple and sensitive electrochemiluminescence (ECL) aptasensor has been developed for bisphenol A (BPA) detection. The capture DNA (CDNA) was modified on the heated indium-tin-oxide (ITO) working electrode surface firstly and then hybridized with BPA aptamer to form double strand DNA (dsDNA). The presence of target can cause the releasing of aptamer from the electrode surface since the aptamer prefers to switch its configuration to combine with BPA. Subsequently, the free CDNA will induce hybridization chain reaction (HCR) to produce long dsDNA on the electrode surface. Ru(phen) 3 2+ can integrate into the grooves of dsDNA to act as an ECL reagent, thus enhanced ECL signal can be detected. The temperature control during the processes of target recognition and HCR were realized through the heated electrode instead of the bulk solution heating. Furthermore, the performance of the ECL aptasensor can be further enhanced at elevated electrode temperature. Under the optimized conditions, the ECL intensity of the system has a linear relationship with the logarithm of BPA concentration in the range of 2.0 pM-50 nM. The limit of detection (LOD) at 55 °C (electrode surface temperature) was calculated to be 1.5 pM, which was approximately 6.5-fold lower than that at 25 °C. The proposed biosensor has been applied to detect the BPA in drink samples with satisfactory results.
危险品化学品经营许可证（带存储）