Zhang Lina, Wang Zhanwei, Zhang Jingbo, Shi Changliang, Sun Xiaoli, Zhao Dan, Liu Baozhong
College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454003, China.
Chemical Laboratory, Medical Instrument Testing Institute of Henan province, Zhengzhou 450018, China.
Nanomaterials (Basel). 2019 Aug 30;9(9):1234. doi: 10.3390/nano9091234.
Efficient and instant detection of biological threat-agent anthrax is highly desired in the fields of medical care and anti-terrorism. Herein, a new ratiometric fluorescence (FL) nanoprobe was elaborately tailored for the determination of 2,6-dipicolinic acid (DPA), a biomarker of anthrax spores, by grafting terbium ions (Tb) to the surface of carbon dots (CDs). CDs with blue FL were fabricated by a simple and green method using schizochytrium as precursor and served as an FL reference and a supporting substrate for coordination with Tb. On account of the absorbance energy transfer emission effect (AETE), green emission peaks of Tb in CDs-Tb nanoprobe appeared at 545 nm upon the addition of DPA. Under optimal conditions, good linearity between the ratio FL intensity of / and the concentrations of DPA was observed within the experimental concentration range of 0.5-6 μM with the detection limit of 35.9 nM, which is superior to several literature studies and significantly lower than the infectious dosage of the spores. Moreover, the CDs-Tb nanoprobe could sensitively detect DPA in the lake water sample. This work offers an efficient self-calibrating and background-free method for the determination of DPA.
在医疗保健和反恐领域，迫切需要高效、即时地检测生物威胁因子炭疽。在此，通过将铽离子（Tb）接枝到碳点（CDs）表面，精心定制了一种新型的比率荧光（FL）纳米探针，用于测定炭疽孢子的生物标志物2,6-吡啶二甲酸（DPA）。以裂殖壶菌为前驱体，通过简单绿色的方法制备了具有蓝色荧光的碳点，其作为荧光参考和与Tb配位的支撑底物。由于吸收能量转移发射效应（AETE），加入DPA后，CDs-Tb纳米探针中Tb的绿色发射峰出现在545nm处。在最佳条件下，在0.5-6μM的实验浓度范围内，/的比率荧光强度与DPA浓度之间呈现良好的线性关系，检测限为35.9 nM，优于多项文献研究，且显著低于孢子的感染剂量。此外，CDs-Tb纳米探针能够灵敏地检测湖水样品中的DPA。这项工作为DPA的测定提供了一种高效的自校准且无背景的方法。
