Henan Province of Key Laboratory of New Optoelectronic Functional Materials, Anyang Normal University, Anyang, Henan, 455000, PR China.
Henan Province of Key Laboratory of New Optoelectronic Functional Materials, Anyang Normal University, Anyang, Henan, 455000, PR China; College of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou, Henan, 450001, PR China.
Anal Chim Acta. 2022 Jun 29;1214:339965. doi: 10.1016/j.aca.2022.339965. Epub 2022 May 21.
This work reported that the peptide-Cu complexes reveal oxidase-mimicking activities for oxygen reduction and ascorbate oxidation. The peptide features a histidine (His) residue in the first position with respect to the free N-terminal amine. The complexes can be easily integrated with nanomaterials such as gold nanoparticles (AuNPs) to form nanocatalysts or nanozymes, which allows for the fabrication of sensitive sensing platforms. To explore the analytical performances of the peptide-Cu complexes in biosensing, sandwich electrochemical and fluorescent immunoassays of prostate specific antigen (PSA) were performed with AuNP/peptide-Cu conjugates as the nanolabels. In the electrochemical immunoassays, the nanolabels coined as nanocatalysts promoted the electrocatalytic reduction of oxygen. For the fluorescent assays of PSA, the nanolabels coined as nanozymes catalyzed the oxidation of ascorbic acid (AA), and the resulting oxidization product dehydroascorbic acid (DHA) was reacted with o-phenylenediamine (OPD) to form fluorescent 3-(dihydroxyethyl)furo [3,4-b]quinoxaline-1-one (DFQ). The electrochemical and fluorescent signals are proportional to the concentration of PSA in the linear range of 0.001-0.50 and 0.001-2.00 ng/mL, respectively. The low detection limits of the methods (0.40 and 1.00 pg/mL) enabled clinical detection of PSA in serum samples. The findings should be valuable for understanding the biological functions of peptide-Cu complexes, and provide new insight to develop optical and electrochemical sensing platforms for clinical diagnosis.
这项工作报道了肽-Cu 配合物具有模拟氧化酶的活性，可用于还原氧气和氧化抗坏血酸。该肽在游离的 N 末端胺的第一个位置具有组氨酸（His）残基。该配合物可以很容易地与纳米材料（如金纳米粒子（AuNPs））结合形成纳米催化剂或纳米酶，从而可以制造灵敏的传感平台。为了探索肽-Cu 配合物在生物传感中的分析性能，使用 AuNP/肽-Cu 缀合物作为纳米标签进行了前列腺特异性抗原（PSA）的夹心电化学和荧光免疫测定。在电化学免疫测定中，纳米标签作为纳米催化剂促进了氧气的电催化还原。对于 PSA 的荧光测定，纳米标签作为纳米酶催化抗坏血酸（AA）的氧化，并且所得氧化产物脱氢抗坏血酸（DHA）与邻苯二胺（OPD）反应形成荧光 3-（二羟乙基）呋喃[3,4-b]喹喔啉-1-酮（DFQ）。电化学和荧光信号与 PSA 在 0.001-0.50 和 0.001-2.00 ng/mL 的线性范围内的浓度成正比。这些方法的低检测限（0.40 和 1.00 pg/mL）能够在血清样品中进行 PSA 的临床检测。这些发现对于理解肽-Cu 配合物的生物学功能应该是有价值的，并为开发用于临床诊断的光学和电化学传感平台提供了新的见解。
