Microfluidic-based biosensors toward point-of-care detection of nucleic acids and proteins

Abstract

This article reviews state-of-the-art microfluidic biosensors of nucleic acids and proteins for pointof-care (POC) diagnostics. Microfluidics is capable of analyzing small sample volumes (10 -9 -10 -18 l) and minimizing costly reagent consumption as well as automating sample preparation and reducing processing time. The merger of microfluidics and advanced biosensor technologies offers new promises for POC diagnostics, including high-throughput analysis, portability and disposability. However, this merger also imposes technological challenges on biosensors, such as high sensitivity and selectivity requirements with sample volumes orders of magnitude smaller than those of conventional practices, false response errors due to non-specific adsorption, and integrability with other necessary modules. There have been many prior review articles on microfluidic-based biosensors, and this review focuses on the recent progress in last 5 years. Herein, we review general technologies of DNA and protein biosensors. Then, recent advances on the coupling of the biosensors to microfluidics are highlighted. Finally, we discuss the key challenges and potential solutions for transforming microfluidic biosensors into POC diagnostic applications.

Gravimetric Viral Diagnostics: QCM Based Biosensors for Early Detection of Viruses

“…Early diagnosis of infectious disease-causing agents such as viruses is essential for clinical and point of care (POC) applications [1][2][3]. Since the viruses have extremely small size and can infect all living beings, i.e., humans, animals, and plants.…”

Quantum dot-based microfluidic biosensor for cancer detection

“…2,3 The miniaturization of numerous bioassays via lab-on-achip (LOC) format can be used to investigate polymerase chain reaction, DNA and cellular analysis, DNA sequencing, immunoassays, and electrophoresis. 4,5 The development of electrochemical biosensors for clinical diagnostics has recently aroused much interest due to their high sensitivity, capability of precise target recognition, and efficient signal transduction.…”

“…6,7 Electrochemical transduction of DNA hybridization relies on monitoring the change in surface properties such as capacitance and impedance with the help of a redox-active species. 2 In case of the DNA hybridization process, wherein the biosensor chip having probe DNA is immersed into a target DNA solution, the diffusion of target DNA to the probe DNA limits the hybridization efficiency. 8 To overcome this problem, electrochemical DNA biosensors can be integrated with microfluidic to accomplish active diffusion of the target with immobilized probes and achieve improved sensitivity of the device.…”

“…8 To overcome this problem, electrochemical DNA biosensors can be integrated with microfluidic to accomplish active diffusion of the target with immobilized probes and achieve improved sensitivity of the device. 2,9,10 Direct electrochemical detection of DNA hybridization can be performed via electrochemical impedance spectroscopy (EIS), which monitors the increased surface charge on the chip as a result of DNA hybridization. 11,12 In this context, a diffusion-restriction model can be applied to miniaturized EIS based biochip nano-volume reactor.…”

Micro- and nanofluidic systems in devices for biological, medical and environmental research

“…Among the requested features of nanoscale structures are the following: a) highly sensitive detection of the desired object / analyte (electric detection, plasmon resonance methods, detection with use nanopores, etc.) [28,29]. b) transport (control the motion of molecules, particles -such as electroosmotic system) [30]; c) filtering and separation [31]; g) control (valves, gates) [32], and others.…”