Hydrogel Gate Graphene Field-Effect Transistors as Multiplexed Biosensors
Hydrogel Gate Graphene Field-Effect Transistors as Multiplexed Biosensors
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DOI：
10.1021/acs.nanolett.9b00431
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发表时间：
2019-04-01
期刊：
影响因子：
10.8
通讯作者：
Jiang, Xiaocheng
中科院分区：
文献类型：
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作者：
Bay, Hamed Hosseini;Vo, Richard;Jiang, Xiaocheng
纳米级场效应晶体管（FET）代表了一个独特的平台，真实的时间，无标记的生化信号转导前所未有的灵敏度和时空分辨率，但他们的翻译实际的生物医学应用仍然具有挑战性。在这里，我们展示了利用生物活性水凝胶作为栅极材料来克服传统FET传感器的几个关键限制的潜力。利用空间限定的光聚合来实现聚乙二醇在单个石墨烯FET器件顶部的选择性图案化，通过该图案化，多个生物特异性受体可以独立地封装到水凝胶门中。青霉素酶的水凝胶介导的整合被证明有效地催化酶促反应在有限的微环境中，使真实的时间，无标记检测青霉素低至0.2 mM。多重功能化与青霉素酶和乙酰胆碱酯酶已被证明实现高度特异性的传感。此外，由水凝胶门产生的微环境已显示出显著减少非靶分子与石墨烯通道的非特异性结合，以及与在一天内显示出显著信号损失的游离酶相比，将包封的酶活性保持至少一周。这种通用方法提出了一种新的生物整合策略，并有助于在同一平台上对生物分析物进行多重检测，这可能会为医疗保健研究带来新的进展。
Nanoscale field-effect transistors (FETs) represent a unique platform for real time, label-free transduction of biochemical signals with unprecedented sensitivity and spatiotemporal resolution, yet their translation toward practical biomedical applications remains challenging. Herein, we demonstrate the potential to overcome several key limitations of traditional FET sensors by exploiting bioactive hydrogels as the gate material. Spatially defined photopolymerization is utilized to achieve selective patterning of polyethylene glycol on top of individual graphene FET devices, through which multiple biospecific receptors can be independently encapsulated into the hydrogel gate. The hydrogel-mediated integration of penicillinase was demonstrated to effectively catalyze enzymatic reaction in the confined microenvironment, enabling real time, label-free detection of penicillin down to 0.2 mM. Multiplexed functionalization with penicillinase and acetylcholinesterase has been demonstrated to achieve highly specific sensing. In addition, the microenvironment created by the hydrogel gate has been shown to significantly reduce the nonspecific binding of nontarget molecules to graphene channels as well as preserve the encapsulated enzyme activity for at least one week, in comparison to free enzymes showing significant signal loss within one day. This general approach presents a new biointegration strategy and facilitates multiplex detection of bioanalytes on the same platform, which could underwrite new advances in healthcare research.