Biosensor-based microRNA detection: techniques, design, performance, and challenges

Abstract

The current state of biosensor-based techniques for amplification-free microRNA (miRNA) detection is critically reviewed. Comparison with non-sensor and amplification-based molecular techniques (MTs), such as polymerase-based methods, is made in terms of transduction mechanism, associated protocol, and sensitivity. Challenges associated with miRNA hybridization thermodynamics which affect assay selectivity and amplification bias are briefly discussed. Electrochemical, electromechanical, and optical classes of miRNA biosensors are reviewed in terms of transduction mechanism, limit of detection (LOD), time-to-results (TTR), multiplexing potential, and measurement robustness. Current trends suggest that biosensor-based techniques (BTs) for miRNA assay will complement MTs due to the advantages of amplification-free detection, LOD being femtomolar (fM)-attomolar (aM), short TTR, multiplexing capability, and minimal sample preparation requirement. Areas of future importance in miRNA BT development are presented which include focus on achieving high measurement confidence and multiplexing capabilities.

Emerging applications of label-free optical biosensors

“…However, NA detection can be challenging relative to other molecular targets because of different reasons: the extremely low concentration of some NA strands like miRNA, which also display expression levels differing by several orders of magnitude; the distributed binding area and the sequence-based recognition, which can be weakened by competing local interactions with low affinity; and, at least for RNA, the fast degradation and the distinctive variety of three-dimensional structures [50]. Recent reviews are available on specific labelfree optical techniques applied to NA detection, like SPR [51,52] or SERS [53], and on detecting specific classes of NA like miRNA [50,54,55].…”

Future microfluidic and nanofluidic modular platforms for nucleic acid liquid biopsy in precision medicine

“…These technologies include methods based on rolling-circle isothermal amplification within hydrogel microparticles to compartmentalize multiple reactions, 105 free-solution electrophoretic detection with drag-tags and single stranded DNA binding protein to increase the differences in electrophoretic mobility of target-probe complexes, 106,107 and other biosensor-based approaches, which have been the focus of several recent reviews. 108,109 In this article, we examine a cluster of microfluidic technologies from our group with potential for POC nucleic acid quantification without PCR amplification, thus eliminating the normalization and selectivity issues of PCR. Without PCR amplification, sensitivity now becomes a challenge, along with other pretreatment related issues.…”

Surface enhanced Raman spectroscopy (SERS) for in vitro diagnostic testing at the point of care

“…Indirect sensing through the identification of optically active molecules, including chromophores and fluorophores or other reporter molecules, has improved the sensitivity and multiplexing capabilities of techniques like Raman or fluorescence spectroscopy while simultaneously lowering the limits of detection (LODs) and broadening the dynamic range of spectroscopic analysis [31,90]. This has led to fluorescence-based POC devices, in particular, as being one of the most widely explored and currently utilized optical modalities for the detection of multiple analytes on a single test.…”

“…It is defined as a group of metabolic diseases where ultimately the body's pancreas does not produce enough insulin or does not properly respond to insulin produced, resulting in high blood sugar levels over a prolonged period. Glucose meters and other POC devices utilize an assortment of methods for detecting and monitoring biomarkers including electrochemical [16][17][18][19][20], magnetic [21][22][23][24][25][26][27][28][29][30], optical [31][32][33][34], label-free spectroscopic analysis [35][36][37][38][39][40][41][42][43], colorimetric [44][45][46][47][48][49], and plasmonic nanoparticle based sensors [50][51][52]. Generally, electrochemical detection uses potentiometric, amperometric, and impedimetric measurements in conjunction with electroactive tags or free flowing electroactive analytes [17][18][19][20] [15,53,54] are examples of electrochemical and colorimet...…”