Bisphenol A Sensors on Polyimide Fabricated by Laser Direct Writing for Onsite River Water Monitoring at Attomolar Concentration

Abstract

This work presents an aptamer-based, highly sensitive and specific sensor for atto- to femtomolar level detection of bisphenol A (BPA). Because of its widespread use in numerous products, BPA enters surface water from effluent discharges during its manufacture, use, and from waste landfill sites throughout the world. On-site measurement of BPA concentrations in water is important for evaluating compliance with water quality standards or environmental risk levels of the harmful compound in the environment. The sensor in this work is porous, conducting, interdigitated electrodes that are formed by laser-induced carbonization of flexible polyimide sheets. BPA-specific aptamer is immobilized on the electrodes as the probe, and its binding with BPA at the electrode surface is detected by capacitive sensing. The binding process is aided by ac electroosmotic effect that accelerates the transport of BPA molecules to the nanoporous graphene-like structured electrodes. The sensor achieved a limit of detection of 58.28 aM with a response time of 20 s. The sensor is further applied for recovery analysis of BPA spiked in surface water. This work provides an affordable platform for highly sensitive, real time, and field-deployable BPA surveillance critical to the evaluation of the ecological impact of BPA exposure.

Laser‐Induced Freestanding Graphene Papers: A New Route of Scalable Fabrication with Tunable Morphologies and Properties for Multifunctional Devices and Structures

“…Additionally, morphologies, properties, and functionalities of LIG can be easily controlled or improved by modifying laser conditions, gas environments, and/or doping agents . These unique characteristics make it highly potential for large‐scale production of varied smart devices, including membrane filters and adsorbents, microsupercapacitors, photodetectors, water splitting/monitoring devices, healthcare and motion‐capturing sensors, and on‐chip biosensors . Unfortunately, the above mentioned applications are unexceptionally relying on the support of substrates.…”

Laser-Scribed Lossy Microstrip Lines for Radio Frequency Applications

“…The laser irradiation regimes ultimately turned to black. Laser carbonization of PI has been investigated previously [8,11]. Here, we focused on the laser procession of silver, since the design of the MS lines were all based on the silver membrane.…”

“…Compared to conventional approaches, this technique offers noncontact and maskless patterning with a resolution that can go down to a submicrometer scale, a localized reaction that makes it less possible to damage the substrate, compatibility with a wide range of materials, and simplified fabrication procedures by combining several process into a single step [1][2][3][4]. These merits meet the requirements for flexible electronic manufactures and lead to many applications, such as conductive electrodes [5,6], capacitors [7][8][9][10], and sensors [2,11,12]. At the same time, the recent literature on laser-scribed electronics is dominated by the transmission and procession of direct current (DC) or low-frequency signals.…”

Thermally stable and uniform DNA amplification with picosecond laser ablated graphene rapid thermal cycling device

“…The use of graphene film has dominated the printed electrode technique for biomedical devices (Du et al 2010;Cheng et al, 2016;Liébana et al, 2016). However, the patterning area and complexity in graphene-based fabrication require considerable improvement in the quality of laser pulse machining.…”