背景:香菇中的香菇多糖被认为是治疗癌症副作用最小的天然药物,但是香菇很容易被不可生物降解的重金属污染,特别是银离子(Ag+)。因此,考虑到它们对香菇药物的不利影响,非常希望监测香菇中的Ag+污染。电化学传感器不受基质浊度和颜色的干扰,并提供了测定变异分析物的有力手段。至于对Ag+的电化学传感,非常需要设计用于特定识别和信号生成的有效信号探针。
结果:我们基于卟啉包裹的MOF(PorMOF)的仿生催化和富含C的DNA的变构开关,提出了用于Ag测定的合适的电化学传感器。由于优异的生物相容性,PorMOF作为纳米酶用于通过加载双链样DNA支架来设计信号探针。由于Ag+对富含胞嘧啶(C)碱基的DNA的特异性识别,远端PorMOF通过C-Ag+-C形成靠近下面的电极,导致用于信号生成的催化羟胺氧化电流增强。利用电流响应与Ag+水平之间的正相关关系,电化学系统为香菇中Ag+的在线监测提供了一种有前途的手段,回收率从92.8%到106.4%,相对标准偏差从3.98%到8.24%,验证电化学传感器对香菇中Ag+的适用性。
■具有可移植性的优点,操作简单,和快速反应,电化学模式为香菇中Ag的在线监测提供了有用的解决方案。通过改变DNA序列,拟议的aptasensor为监测其他重金属提供了一种强有力的方法,能够保护药物生产免受重金属污染。
BACKGROUND: Lentinan medicament from Lentinus edodes has been considered as natural medicinal products with minimal side effects for cancer therapy, but Lentinus edodes are easily polluted by nonbiodegradable heavy metals, especially silver ion (Ag+). Therefore, it is highly desirable to monitor Ag + pollution in Lentinus edodes considering their adverse impact on lentinan medicament. Electrochemical sensor isn\'t affected from the interference of matrix turbidity and color, and offers a powerful means for determination of variant analytes. As for electrochemical sensing toward Ag+, there is a great need to design efficient signal probes for specific recognition and signal generation.
RESULTS: We present an appropriate electrochemical aptasensor for Ag + assay based on biomimetic catalysis of porphyrin-encapsulated MOF (PorMOF) and allosteric switch of C-rich DNA. Thanks to the excellent biocompatibility, PorMOFs as nanozyme are used to design signal probes by loading duplex-like DNA scaffold. Owing to the specific recognition of Ag+ toward cytosine (C) base-rich DNA, PorMOF at the distal end was close to the underlying electrode via C-Ag+-C formation, leading to an enhanced current of catalytic hydroxylamine oxidation for signal generation. Using the positive correlation between current response and Ag+ level, the electrochemical system provides a promising means for on-line monitoring of Ag+ in Lentinus edodes with recoveries from 92.8% to 106.4% and relative standard deviation from 3.98% to 8.24%, verifying the applicability of the electrochemical aptasensor toward Ag+ in Lentinus edodes.
UNASSIGNED: With merits of portability, simple operation, and rapid response, the electrochemical pattern offers a useful solution for on-line monitoring of Ag+ in Lentinus edodes. By altering the DNA sequence, the proposed aptasensor provides a powerful way for monitoring other heavy metals, capable of protecting medicament production from heavy metal pollution.