Miller Philip R, Skoog Shelby A, Edwards Thayne L, Wheeler David R, Xiao Xiaoyin, Brozik Susan M, Polsky Ronen, Narayan Roger J
Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, USA.
J Vis Exp. 2012 Jun 1(64):e4067. doi: 10.3791/4067.
The development of a minimally invasive multiplexed monitoring system for rapid analysis of biologically-relevant molecules could offer individuals suffering from chronic medical conditions facile assessment of their immediate physiological state. Furthermore, it could serve as a research tool for analysis of complex, multifactorial medical conditions. In order for such a multianalyte sensor to be realized, it must be minimally invasive, sampling of interstitial fluid must occur without pain or harm to the user, and analysis must be rapid as well as selective. Initially developed for pain-free drug delivery, microneedles have been used to deliver vaccines and pharmacologic agents (e.g., insulin) through the skin. Since these devices access the interstitial space, microneedles that are integrated with microelectrodes can be used as transdermal electrochemical sensors. Selective detection of glucose, glutamate, lactate, hydrogen peroxide, and ascorbic acid has been demonstrated using integrated microneedle-electrode devices with carbon fibers, modified carbon pastes, and platinum-coated polymer microneedles serving as transducing elements. This microneedle sensor technology has enabled a novel and sophisticated analytical approach for in situ and simultaneous detection of multiple analytes. Multiplexing offers the possibility of monitoring complex microenvironments, which are otherwise difficult to characterize in a rapid and minimally invasive manner. For example, this technology could be utilized for simultaneous monitoring of extracellular levels of, glucose, lactate and pH, which are important metabolic indicators of disease states (e.g., cancer proliferation) and exercise-induced acidosis.
开发一种用于快速分析生物相关分子的微创多重监测系统，可为患有慢性疾病的个体提供对其即时生理状态的便捷评估。此外，它还可作为分析复杂多因素疾病的研究工具。为了实现这样一种多分析物传感器，它必须是微创的，间质液采样过程必须对用户无痛且无害，并且分析必须快速且具有选择性。微针最初是为无痛给药而开发的，已被用于通过皮肤输送疫苗和药物制剂（如胰岛素）。由于这些装置可进入间质空间，与微电极集成的微针可作为经皮电化学传感器。使用带有碳纤维、修饰碳糊和铂涂层聚合物微针作为传感元件的集成微针电极装置，已证明可以选择性检测葡萄糖、谷氨酸、乳酸、过氧化氢和抗坏血酸。这种微针传感器技术为原位同时检测多种分析物提供了一种新颖而精密的分析方法。多重检测提供了监测复杂微环境的可能性，否则很难以快速且微创的方式对其进行表征。例如，该技术可用于同时监测葡萄糖、乳酸和pH值的细胞外水平，这些是疾病状态（如癌症增殖）和运动诱导酸中毒的重要代谢指标。
