Nanomaterials-Based Fluorimetric Methods for MicroRNAs Detection

Abstract

MicroRNAs (miRNAs) are small endogenous non-coding RNAs of ~22 nucleotides that play important functions in the regulation of many biological processes, including cell proliferation, differentiation, and death. Since their expression has been in close association with the development of many diseases, recently, miRNAs have been regarded as clinically important biomarkers and drug discovery targets. However, because of the short length, high sequence similarity and low abundance of miRNAs in vivo, it is difficult to realize the sensitive and selective detection of miRNAs with conventional methods. In line with the rapid development of nanotechnology, nanomaterials have attracted great attention and have been intensively studied in biological analysis due to their unique chemical, physical and size properties. In particular, fluorimetric methodologies in combination with nanotechnology are especially rapid, sensitive and efficient. The aim of this review is to provide insight into nanomaterials-based fluorimetric methods for the detection of miRNAs, including metal nanomaterials, quantum dots (QDs), graphene oxide (GO) and silicon nanoparticles.

Label-Free MicroRNA Optical Biosensors

“…SPR have also gained significant attention in both fundamental research and industry after its commercialization in 1990 by Biacore (GE Health care). Currently, SPR biosensors are commercialized by many companies all over the world [61] and have recently gained attention for miRNA detections [25,30,45,62,63,64]. The principle and applications of SPR biosensors have been well reviewed [56,57,60].…”

“…In this approach, the LNA probes were demonstrated to be successful in enabling the direct label-free detection of miRNA-93 and signal amplification was achieved using RNA–DNA-hybrid antibody. This signal amplification strategy yields excellent results, and many studies have employed similar amplification method (Table 1) whereby the overall mass or size of the target biomolecule is increased via bioconjugation to other biomolecules or nanoparticles, and hence a significant enhancement of the signal [45,75,76,77,78].…”

“…Conventional techniques used for assaying miRNAs [32,38], such as northern blotting [39,40], quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), and cDNA microarrays [41,42,43] are extremely complicated, time-consuming, laborious, cost-ineffective and exhibit poor sensitivity. These challenges are attributed to the intrinsic properties of miRNAs such as their low mass, short sequence length, high sequence similarity, low abundance (∼0.01% of the total mass), and only a few molecules per cell [44,45,46].…”

Polydopamine-assisted versatile modification of a nucleic acid probe for intracellular microRNA imaging and enhanced photothermal therapy

“… 3 However, these methods are not suitable for monitoring the expression of intracellular miRNA in living cells. Due to the rapid development of optical imaging techniques, several imaging methods 4 have been established to visualize intracellular miRNA, which may help us to understand the role of intracellular miRNA in cellular processes and thus further provide a basis for diagnosis and treatment of cancer.…”

A signal-on homogeneous electrochemical biosensor for sequence-specific microRNA based on duplex-specific nuclease-assisted target recycling amplification

“…25 A simple and ultrasensitive electrochemical approach was reported for miRNA detection based on duplex-specic nuclease-assisted target recycling and signal amplication of alkaline phosphatase plus redox cycling. 26 An ultrasensitive electrochemical method was constructed based on target triggered hairpin DNA opening to achieve nanoparticle localization and hybridization chain reaction dual amplication for miRNA detection. 27 A novel electrochemical biosensor was designed for highly sensitive detection of miRNAs based on catalyzed hairpin assembly target recycling and cascade electrocatalytic signal amplication.…”