Engineered crRNA for CRISPR/Cas-assisted biosensing.

CRISPR/Cas-based diagnostics (CRISPR-Dx) face challenges, including difficulty in detecting ultrashort nucleotides, preamplification dependency, cross-contamination, insufficiency in on-pot detection paradigms, and inconvenience in detecting non-nucleic acid targets. This forum outlines the advances in engineered CRISPR RNA (crRNA) that address the aforementioned problems, highlighting challenges, opportunities, and future directions.

Semiarbitrary qPCR for Sensitive Detection of Circulating miRNA via Terminal Deoxynucleotidyl Transferase-Assisted RNA-Primed DNA Polymerization.

Circulating microRNAs (miRNAs) have recently emerged as noninvasive disease biomarkers. Quantitative detection of circulating miRNAs could offer significant information for clinical diagnosis due to its significance in the development of biological processes. In response to the current challenges of circulating miRNA detection, we introduce a sensitive, selective, and versatile circulating miRNA detection strategy using terminal deoxynucleotidyl transferase (TdT)-catalyzed RNA-primed DNA polymerization (TCRDP) coupled with semiarbitrary qPCR (SAPCR).

Recent Advances of DNA-Templated Metal Nanoclusters for Food Safety Detection: From Synthesis, Applications, Challenges, and Beyond.

Food safety concerns have become a significant threat to human health and well-being, catching global attention in recent years. As a result, it is imperative to research conceptually novel biosensing and effective techniques for food matrices detection. Currently, DNA-templated metal nanoclusters (DNA-MNCs) are considered as one of the most promising nanomaterials due to their excellent properties in biosensing.

pH-Responsive Mucus-Penetrating Nanoparticles for Enhanced Cellular Internalization by Local Administration in Vaginal Tissue.

Low mucus penetration ability and cellular uptake seriously limit the effectiveness of local vaginal drug administration because of the rapid foreign particulate and pathogen removal property of the mucus layer. Our previous work proved that nanoparticles with a highly dense polyethylene glycol (PEG) coating can penetrate mucus rapidly (mucus-penetrating nanoparticles, MPPs) and improve drug distribution and retention at mucosal surfaces. However, the "stealth-effect" of the PEG coating also restricts cellular uptake of MPPs.

A lateral flow strip biosensor platform based on cascade nucleic acid amplification technology for ultrasensitive detection of OSCC-associated salivary MicroRNA.

Oral squamous cell carcinoma (OSCC) is the well-known malignancy and poses a serious threat to human health with high morbidity and mortality. Early detection and treatment can improve the recovery rate and reduce complications of OSCC. Therefore, we designed a lateral flow strip biosensor platform (HRCA-strip) based on the cascade nucleic acid amplification technology (HRCA) for colorimetric analysis of OSCC-associated has-microRNA 31-5p (miRNA 31).

An amplified fluorescent biosensor for Ag detection through the hybridization chain reactions.

Ag is widely distributed in nature and it is used in almost all areas of human life. However, due to the widespread use of Ag materials, Ag pollution seriously threatens the human health and environment. The traditional detection methods for Ag suffer from disadvantages including high operational cost, complicated operating unit and instrument, and high requirements for professionals.

High fluorescence quenching probe-based reverse fluorescence enhancement LFTS coupling with IS-primer amplification reaction for the rapid and sensitive Parkinson Disease-associated MicroRNA detection.

Parkinson Disease (PD) is the second-most common neurodegenerative disorder in the population. Recent researches indicated that hsa-microRNA 5010-3p (miR-5010) and hsa-microRNA 331-5p (miR-331) were significantly important for the detection of PD. So, in this work, a kind of high fluorescence quenching probe-based reverse fluorescence enhancement lateral flow test strip (rLFTS) was constructed to realize the synchronous detection of miR-5010 and miR-331.

Nonenzyme Cascaded Amplification Biosensor Based on Effective Aggregation Luminescence Caused by Disintegration of Silver Nanoparticles.

Sensitive and portable quantification of biomarkers has particular significance in the monitoring and treatment of clinical diseases. Conventional immunoassays were accustomed to introducing or incorporating enzymes for signal amplification, which commonly suffered from poor stability and inferior tolerance. Herein, we constructed a novel nonenzyme amplification methodology based on fluorogenic Ag-tetrazolate aggregation coupled with silver corrosion sensitization for biomarker determination.

A fluorescent signal "removal" sensor via duplex-specific nuclease-aided cleavage for miRNA detection in flow cytometry.

Considered as the next-generation biomarkers, microRNAs play an important role in the early diagnosis of cancers. Here, we designed a fluorescent signal "removal" sensor for one-step, sensitive and specific detection of multiple microRNAs by flow cytometry (FCM). In this work, single-stranded DNA (ssDNA), working as the interlinkage, immobilized the fluorescent nanosphere (FS) onto the SiO microspheres surface to form the SiO-ssDNA-FS probes.

Reusable Bioluminescent Sensor for Ultrasensitive MicroRNA Detection Based on a Target-Introducing "Fuel-Loading" Mechanism.

As a kind of important potential biomarkers, the expression level of some microRNAs (miRNAs) is closely related to cancer development and progression. Herein, a reusable ultra-sensitive "fuel-loadings" bioluminescent sensor was constructed to detect the trace miRNA based on the cascading signal amplification, which combined the target-introducing "fuel-loading" mechanism and cyclic bioluminescence assay. In this sensor, magnetic beads labeled with hairpin DNA probes (hDNA) could specifically hybridize with the target miRNA and isolate these targets from samples.

Enzyme-free colorimetric detection of MicroRNA-21 using metal chelator as label for signal generation and amplification.

MicroRNAs (miRNAs) were reported to be potential tumor markers for early diagnosis of cancer. Due to its short sequence, low expression level and high susceptibility to degradation, the stable and sensitive detection method of miRNAs is arduous to establish. In this work, we designed a metal chelator (ethylenediamine tetraacetic acid disodium salt, EDTA•2Na) labeled oligonucleotides as the plasmonic signal supraregulator probe to control the generation of gold nanoparticles (AuNPs).

An innovative "unlocked mechanism" by a double key avenue for one-pot detection of microRNA-21 and microRNA-141.

The accurate and quantitative detection of microRNAs (miRNAs) as next-generation, reliable biomarkers will provide vital information for cancer research and treatment. However, their unique, intrinsic features pose quite a challenge for miRNA profiling, especially for multiplexed detection. Thus, there is a strong and an ever-growing need to develop an accurate, simple, sensitive and specific miRNA sensing method.

A Metal Chelator as a Plasmonic Signal-Generation Superregulator for Ultrasensitive Colorimetric Bioassays of Disease Biomarkers.

Enzyme-based assays have been widely applied in clinical diagnosis for decades. However, the intrinsic limitations of enzymes, such as low operation stability, mediocre sensitivity, and high cost in production and purification, heavily constrain their detection application. Here, an enzyme-free assay is reported that relies on the strong chelating capability of ethylenediamine tetraacetic acid disodium salt (EDTA•2Na, the chelator) for Au ions, in which the cheap EDTA•2Na labeled by targeting moieties can selectively regulate the growth of plasmonic gold nanoparticles (AuNPs) at the target site subjecting to the concentration of analyte in samples.

Effective Bioactivity Retention of Low-Concentration Antibodies on HFBI-Modified Fluorescence ICTS for Sensitive and Rapid Detection of PSA.

Nowadays, increasing analytical sensitivity is still a big challenge in constructing membrane-based fluorescence immunochromatography test strips (FICTS). However, the bioactivity of antibody (Ab) immobilized on the test line (T line) of porous nitrocellulose membrane (PNM), which directly influences the analytical sensitivity, is less studied. In this work, a novel amphiphilic hydrophobin (HFBI) protein was introduced to modify the T line to effectively retain the Abs' bioactivity.

High sensitive and multiple detection of acute myocardial infarction biomarkers based on a dual-readout immunochromatography test strip.

Immunochromatography test strip (ICTS) displayed high advantages in screening acute myocardial infarction (AMI) biomarkers. However, the low sensitivity and nonquantitative results seriously limited its clinical application. Herein, we designed a highly sensitive, quantitative and dual-readout ICTS for assaying multiple AMI biomarkers based on magnetic nanoparticles (MNPs) quenching the fluorescence of Cy5, which was labeled on capture antibodies on test (T) lines.

Simple and Sensitive Quantification of MicroRNAs via PS@Au Microspheres-Based DNA Probes and DSN-Assisted Signal Amplification Platform.

Identifying the microRNA (miRNA) expression level can provide critical information for early diagnosis of cancers or monitoring the cancer therapeutic efficacy. This paper focused on a kind of gold-nanoparticle-coated polystyrene microbeads (PS@Au microspheres)-based DNA probe as miRNA capture and duplex-specific nuclease (DSN) signal amplification platform based on an RGB value readout for detection of miRNAs. In virtue of the outstanding selectivity and simple experimental operation, 5'-fluorochrome-labeled molecular beacons (MBs) were immobilized on PS@Au microspheres via their 3'-thiol, in the wake of the fluorescence quenching by nanoparticle surface energy transfer (NSET).

Fluorescence quenching-based signal amplification on immunochromatography test strips for dual-mode sensing of two biomarkers of breast cancer.

Recently, immunochromatography test strips (ICTS) have been fully developed for point-of-care testing (POCT). However, the intrinsic limitations including non-quantitative detection of colloidal gold ICTS and low sensitivity of fluorescence ICTS (FICTS) significantly restrict their further application in clinical diagnosis. Taking advantages of rapid colorimetric qualitative detection and fluorescence quantitation, we designed a kind of sensitive and dual-mode magnetic FICTS (mFICTS) based on PLGA@Fe3O4 super-paramagnetic nanosphere (SPMN) probes quenching multiplex fluorescer on the test line through sandwich immunoreactions.

A review of fluorescent signal-based lateral flow immunochromatographic strips.

Fluorescent signal-based lateral flow immunochromatographic strips (FLFICS) have received great expectations since they effectively improve detection sensitivity with quantitative analysis, and still retain the advantages of simplicity, rapidness, and portability of a common lateral flow immunochromatographic strip (LFICS). Diverse fluorescent reporters have promoted development of FLFICS, such as fluorescent dyes, quantum dots (QDs), an up-converting phosphor (UCP), lanthanide labels, and other fluorescence nanoparticles. In this work, we discuss the different fluorescent reporters applied with LFICS and their unique properties as well as signal amplification strategies helping to enhance detection performance.

The construction of a novel nucleic acids detection microplatform based on the NSET for one-step detecting TK1-DNA and microRNA-21.

Microbeads-based microchip technology has become the potential for a new generation of nucleic acids detection in a high-throughput and sensitive manner. However the specificity and operational complexity limit the microchip applied in nucleic acids detection. Herein, in this work, we designed a kind of gold-nanoparticles coated polystyrene microbeads as microplatform conjugating with the molecular beacons as probes.

Enhanced Fluorescence ELISA Based on HAT Triggering Fluorescence "Turn-on" with Enzyme-Antibody Dual Labeled AuNP Probes for Ultrasensitive Detection of AFP and HBsAg.

At present, enzyme-linked immunosorbent assay (ELISA) is considered to be the most appropriate approach in clinical biomarker detection, with good specificity, low cost, and straightforward readout. However, unsatisfactory sensitivity severely hampers its wide application in clinical diagnosis. Herein, we designed a new kind of enhanced fluorescence enzyme-linked immunosorbent assay (FELISA) based on the human alpha-thrombin (HAT) triggering fluorescence "turn-on" signals.