Microfluidic Reactors for Diagnostics Applications

Abstract

Diagnostic assays are an important part of health care, both in the clinic and in research laboratories. In addition to improving treatments and clinical outcomes, rapid and reliable diagnostics help track disease epidemiology, curb infectious outbreaks, and further the understanding of chronic illness. Disease markers such as antigens, RNA, and DNA are present at low concentrations in biological samples, such that the majority of diagnostic assays rely on an amplification reaction before detection is possible. Ideally, these amplification reactions would be sensitive, specific, inexpensive, rapid, integrated, and automated. Microfluidic technology currently in development offers many advantages over conventional benchtop reactions that help achieve these goals. The small reaction volumes and energy consumption make reactions cheaper and more efficient in a microfluidic reactor. Additionally, the channel architecture could be designed to perform multiple tests or experimental steps on one integrated, automated platform. This review explores the current research on microfluidic reactors designed to aid diagnostic applications, covering a broad spectrum of amplification techniques and designs.

Preparation of homogeneous CNT coatings in insulating capillary tubes by an innovative electrochemically-assisted method

“…Microreactors are considered a tool with the potential to push forward many industrial and lab processes which cannot be efficiently handled in conventional reactors [5,6]. It is well established that in many cases synthetic chemistry [7,3], clinical analysis [8,9] and power supply devices [10,11] can benefit from miniaturization. The reason behind these claims is mainly the optimization of heat and mass transfer due to their large surface-to-volume ratios.…”

Microfluidic platform for isolating nucleic acid targets using sequence specific hybridization

“…We employed a well-known amplification method: nucleic acid sequence based amplification (NASBA), 15 which occurs isothermally at 41 C using three enzymes: T7 RNA polymerase, avian myeloblastosis virus reverse transcriptase (AMV-RT), and RNAseH. The reagents used for NASBA and their concentrations at the final reaction volume were 40 mmol/l Tris (pH 8.0), 12.5 mmol/l MgCl 2 , 73.5 mmol/l CH 3 COOK, 5.25 mmol/l dithiothreitol, 1.05 mmol/l dNTP, 2.1 mmol/l rNTP, 0.21 mmol/l each primer, 52.5 nmol/l molecular beacon, 15.75% dimethyl sulfoxide, 1.68 U/ml T7 RNA polymerase, 0.34 U/ml AMV-RT, 0.005 U/ml RNase-H, and 0.11 mg/ml bovine serum albumin.…”

Smart Microfluidics: The Role of Stimuli- Responsive Polymers in Microfluidic Devices

“…The first one involves the fabrication of miniaturized functional units and their assembly level by level to achieve desired functionalities. Indeed, microfluidic devices have planar structures that can be easily integrated with mechanical, electronic, fluid functions and optical elements (Balslev et al, 2006;Verpoorte, 2003a) According to this approach, a great variety of microfabrication techniques have been developed for manufacturing microfluidic networks integrating advanced functions, such as pumps, (Laser & Santiago, 2004) valves, (Oh & Ahn, 2006) mixers, (Nguyen & Wu 2005) membranes, (de Jong et al, 2006) reactors (McCalla & Tripathi, 2011) and heating and cooling elements. (Chen et al, 2007) The discussion on the lab-on-chip technologies is beyond the scope of this review and the readers are addressed on recent reviews.…”