Bu Shengjun, Wang Kuiyu, Wang Chengyu, Li Zhongyi, Hao Zhuo, Liu Wensen, Wan Jiayu
Institute of Military Veterinary, Academy of Military Medical Sciences, Changchun, 130122, China.
School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, China.
Mikrochim Acta. 2020 Nov 28;187(12):679. doi: 10.1007/s00604-020-04657-1.
A point-of-care (POC) immunoassay was established for the sensitive and rapid detection of pathogenic Escherichia coli O157:H7, using magnetic FeO organic-inorganic composites (Ab@FeO) for immunomagnetic separation, nanozyme platinum nanoparticle (PtNp) organic-inorganic composites (Ap@PtNp) for signal amplification, and thermometer readings. Antibodies and FeO were incubated in Cu phosphate buffer to synthesize the magnetic composite Ab@FeO with antibodies, to specifically capture E. coli O157:H7. Antimicrobial peptides and PtNp were incubated in Cu phosphate buffer to synthesize the signal composites Ap@PtNp with antimicrobial peptides (magainin I), recognizing and labeling E. coli O157:H7. In the presence of E. coli O157:H7, magnetic microcomposites targeted bacteria and signal microcomposites to form the sandwich structure: Ab@FeO-bacteria-Ap@PtNp for magnetic separation. Ap@PtNp of signal composites catalyzed HO to generate thermo-signals (temperature rise), which were determined by a thermometer. This point-of-care bioassay detected E. coli O157:H7 in the linear range of 10-10 CFU mL and with a detection limit of 14 CFU mL. One-pot process magnetic FeO organic-inorganic composites (Ab@FeO, magnetic microcomposites, MMC) for immunomagnetic separation and nanozyme platinum nanoparticle (PtNp) organic-inorganic composites (Ap@PtNp, signal microcomposites, SMC) were used as signal amplification and thermometer readings for E. coli O157:H7 detection.
建立了一种即时检测（POC）免疫分析法，用于灵敏快速地检测致病性大肠杆菌O157:H7，该方法使用磁性FeO有机-无机复合材料（Ab@FeO）进行免疫磁分离，纳米酶铂纳米颗粒（PtNp）有机-无机复合材料（Ap@PtNp）进行信号放大，并通过温度计读数进行检测。将抗体与FeO在磷酸铜缓冲液中孵育，以合成带有抗体的磁性复合材料Ab@FeO，用于特异性捕获大肠杆菌O157:H7。将抗菌肽与PtNp在磷酸铜缓冲液中孵育，以合成带有抗菌肽（蛙皮素I）的信号复合材料Ap@PtNp，并识别和标记大肠杆菌O157:H7。在存在大肠杆菌O157:H7的情况下，磁性微复合材料靶向细菌，信号微复合材料形成夹心结构：Ab@FeO-细菌-Ap@PtNp用于磁分离。信号复合材料的Ap@PtNp催化HO产生热信号（温度升高），由温度计测定。这种即时生物测定法在10-10 CFU mL的线性范围内检测大肠杆菌O157:H7，检测限为14 CFU mL。一锅法制备的磁性FeO有机-无机复合材料（Ab@FeO，磁性微复合材料，MMC）用于免疫磁分离，纳米酶铂纳米颗粒（PtNp）有机-无机复合材料（Ap@PtNp，信号微复合材料，SMC）用作信号放大和温度计读数，用于检测大肠杆菌O157:H7。
