Sipuka Dimpo S, Olorundare Foluke O G, Makaluza Sesethu, Midzi Nyasha, Sebokolodi Tsholofelo I, Arotiba Omotayo A, Nkosi Duduzile
Department of Chemical Sciences, University of Johannesburg, Doornfontein, 2028 Johannesburg, South Africa.
Centre for Nanomaterials Science Research, University of Johannesburg, 2028 Johannesburg, South Africa.
ACS Omega. 2023 Sep 5;8(37):33403-33411. doi: 10.1021/acsomega.3c03133. eCollection 2023 Sep 19.
Dopamine is an important neurotransmitter and biomarker that plays a vital role in our neurological system and body. Thus, it is important to monitor the concentration levels of dopamine in our bodies. We report an aptamer-based sensor fabricated through an electro-co-deposition of a generation 3 poly(propylene imine) (PPI) dendrimer and gold nanoparticles (AuNPs) on a glassy carbon (GC) electrode by cyclic voltammetry. Through self-assembly, a single-stranded thiolated dopamine aptamer was immobilized on the GC/PPI/AuNPs electrode to prepare an aptasensor. Voltammetry and electrochemical impedance spectroscopy (EIS) were used to characterize the modified electrodes. The readout for the biorecognition event between the aptamer and various dopamine concentrations was attained from square wave voltammetry and EIS. The aptasensor detected dopamine from the range of 10-200 nM, with a limit of detection of 0.26 and 0.011 nM from SWV and EIS, respectively. The aptasensor was selective toward dopamine when different amounts of epinephrine and ascorbic acid were present. The aptasensor was applicable in a more complex matrix of human serum.
多巴胺是一种重要的神经递质和生物标志物，在我们的神经系统和身体中起着至关重要的作用。因此，监测我们体内多巴胺的浓度水平很重要。我们报告了一种基于适体的传感器，该传感器通过循环伏安法在玻碳（GC）电极上通过电共沉积第三代聚（丙烯亚胺）（PPI）树枝状大分子和金纳米颗粒（AuNP）制备而成。通过自组装，将单链硫醇化多巴胺适体固定在GC/PPI/AuNP电极上以制备适体传感器。伏安法和电化学阻抗谱（EIS）用于表征修饰电极。适体与不同多巴胺浓度之间的生物识别事件的读数通过方波伏安法和EIS获得。该适体传感器检测多巴胺的范围为10 - 200 nM，通过方波伏安法和EIS的检测限分别为0.26和0.011 nM。当存在不同量的肾上腺素和抗坏血酸时，该适体传感器对多巴胺具有选择性。该适体传感器适用于更复杂的人血清基质。
