A Propidium Monoazide-Assisted Digital CRISPR/Cas12a Assay for Selective Detection of Live Bacteria in Sample.

O157:H7 ( O157:H7) is a prominent pathogenic bacterium that poses serious risks to food safety and public health. Rapid and accurate detection of live O157:H7 is of great importance in food quality monitoring and clinical diagnosis. Here, we report a propidium monoazide-assisted nonamplification digital CRISPR/Cas12a assay for sensitive and rapid detection of live O157:H7.

CRISPR-Based Biosensors for Medical Diagnosis: Readout from Detector-Dependence Detection Toward Naked Eye Detection.

The detection of biomarkers (such as DNA, RNA, and protein) plays a vital role in medical diagnosis. The CRISPR-based biosensors utilize the CRISPR/Cas system for biometric recognition of targets and use biosensor strategy to read out biological signals without the employment of professional operations. Consequently, the CRISPR-based biosensors demonstrate great potential for the detection of biomarkers with high sensitivity and specificity.

Digital Recombinase Polymerase Amplification, Digital Loop-Mediated Isothermal Amplification, and Digital CRISPR-Cas Assisted Assay: Current Status, Challenges, and Perspectives.

Digital nucleic acid detection based on microfluidics technology can quantify the initial amount of nucleic acid in the sample with low equipment requirements and simple operations, which can be widely used in clinical and in vitro diagnosis. Recently, isothermal amplification technologies such as recombinase polymerase amplification (RPA), loop-mediated isothermal amplification (LAMP), and clustered regularly interspaced short palindromic repeats-CRISPR associated proteins (CRISPR-Cas) assisted technologies have become a hot spot of attention and state-of-the-art digital nucleic acid chips have provided a powerful tool for these technologies. Herein, isothermal amplification technologies including RPA, LAMP, and CRISPR-Cas assisted methods, based on digital nucleic acid microfluidics chips recently, have been reviewed.

A portable, high-throughput real-time quantitative PCR device for point-of-care testing.

Nucleic acids detection has become essential in the identification of many infectious diseases and tumors. Conventional qPCR instruments are not suitable for point-of-care Moreover, current miniaturized nucleic acid detection equipment has limited throughput and multiplex detection capabilities, typically allowing the detection of a limited number of samples. Here, we present an affordable, portable, and high-throughput nucleic acid detection device for point-of-care detection.

Adsorption-Free Self-Priming Direct Digital Dual-crRNA CRISPR/Cas12a-Assisted Chip for Ultrasensitive Detection of Pathogens.

Rapid and sensitive pathogen detection methods are critical for disease diagnosis and treatment. RPA-CRISPR/Cas12 systems have displayed remarkable potential in pathogen detection. A self-priming digital PCR chip is a powerful and attractive tool for nucleic detection.

Recent advances in integrated microfluidics for liquid biopsies and future directions.

Liquid biopsies have piqued the interest of researchers as a new tumor diagnosis technique due to their unique benefits of non-invasiveness, sensitivity, and convenience. Recent advances in microfluidic technology have integrated separation, purification, and detection, allowing for high-throughput, high-sensitivity, and high-controllability detection of specific biomarkers in liquid biopsies. With the increasing demand for tumor detection and individualized treatment, new challenges are emerging for the ever-improving microfluidic technology.

DCD-chip designed for the digital and ultraprecise quantification of copy number variation.

Copy number variation (CNV), including genomic deletions and duplication, has been associated with many kinds of diseases. It is crucial to precisely quantify the copy number variation of samples among patients, which may guide treatment. Digital PCR (dPCR) enables high-resolution CNV analysis through the ultraprecise absolute quantification of specific nucleic acid sequences.

A direct and multiplex digital PCR chip for EGFR mutation.

Digital PCR is a sensitive detection method, which has important applicability in liquid biopsy through the measurement of ctDNA. However, the current sample pre-processing of ctDNA and the multiplex detection capability of digital PCR have limitations. In view of the above two aspects, we developed a digital PCR chip with multiplex capability and established a direct amplification detection method without nucleic acid extraction.

Ginseng of different ages is affected by the accumulation of heavy metals in ginseng soil.

Heavy-metal pollution has been established to affect ginseng quality. However, this effect is still unknown in ginseng of different ages, emphasizing the need to investigate the effects of heavy metals in soils on ginseng growth. Herein, we determined the content of heavy metals (Cu, Cd, Pb, Hg, and As) in ginseng of different ages (2 to 6-year-old) and the corresponding soil samples.

Blue light induces ROS mediated apoptosis and degradation of AML1-ETO oncoprotein in Kasumi-1 cells.

Light-emitting diode (LED)-based therapies, particularly blue LEDs with wavelengths of 400-500 nm, have shown beneficial results in several cancers, including melanoma, lymphoid cells, and skin tumors. In this study, the cell viability and apoptosis of Kasumi-1 cells treated by blue light (BL) irradiation have been explored. Firstly, BL can specially inhibit the proliferation and promote the apoptosis of Kasumi-1 cells.

Direct digital polymerase chain reaction chip for the detection of EGFR T790M mutation in plasma.

Nucleic acid extraction and purification before amplification is considered an essential step for nucleic acid amplification testing. However, this may cause losses or introduce errors that can lead to inaccurate results, especially when using samples with a small nucleic acid concentration. Here, we developed a direct digital chip that enabled us to detect nucleic acid without DNA extraction and purification.

Microfluidic devices for multiplexed detection of foodborne pathogens.

The global burden of foodborne diseases is substantial and foodborne pathogens are the major cause for human illnesses. In order to prevent the spread of foodborne pathogens, detection methods are constantly being updated towards rapid, portable, inexpensive, and multiplexed on-site detection. Due to the nature of the small size and low volume, microfluidics has been applied to rapid, time-saving, sensitive, and portable devices to meet the requirements of on-site detection.

A multiplex and fast detection platform for microRNAs based on a self-priming microfluidic chip and duplex-specific nuclease.

MicroRNA expression levels highly correlate with the occurrence, diagnosis and prognosis of disease. However, challenges remain in establishing a multiplex and fast detection method. Here, we developed a multiplex and fast detection platform for microRNAs based on a self-priming microfluidic chip and duplex-specific nuclease.

A Self-Priming Digital Polymerase Chain Reaction Chip for Multiplex Genetic Analysis.

Digital PCR (polymerase chain reaction) is a powerful and attractive tool for the quantification of nucleic acids. However, the multiplex detection capabilities of this system are limited or require expensive instrumentation and reagents, all of which can hinder multiplex detection goals. Here, we propose strategies toward solving these issues regarding digital PCR.

Advanced "lab-on-a-chip" to detect viruses - Current challenges and future perspectives.

Massive viral outbreaks draw attention to viruses that have not been thoroughly studied or understood. In recent decades, microfluidic chips, known as "lab-on-a-chip", appears as a promising tool for the detection of viruses. Here, we review the development of microfluidic chips that could be used in response to viral detection, specifically for viruses involved in more recent outbreaks.

Rapid In Situ Photoimmobilization of a Planar Droplet Array for Digital PCR.

Digital PCR (dPCR) is a powerful technique capable of absolute quantification of nucleic acids with good accuracy. Droplet-based dPCR (ddPCR), among others, is one of the most important dPCR techniques. However, the surface tension-controlled droplets may suffer from fusion/fission due to the vigorous temperature change in PCR thermal cycling.

A "sample-in-multiplex-digital-answer-out" chip for fast detection of pathogens.

Point-of-care (POC) testing offers rapid diagnostic results. However, the quantification of current methods is performed using standard curves and external references, and not direct and absolute quantification. This paper describes an integrated multiplex digital recombinase polymerase amplification (ImdRPA) microfluidic chip which combines DNA extraction, multiplex digital RPA and fluorescence detection together in one chip, creating a "sample-in-multiplex-digital-answer-out" system.

Diverse autophagy and apoptosis in myeloid leukemia cells induced by 20(s)-GRh2 and blue LED irradiation.

Autophagy is an important mechanism for cell death regulation. To improve the anticancer effect during the treatment of leukemia and promote the apoptosis of leukemic cells, it is important to define the relationship between autophagy and apoptosis. A key bioactive compound in traditional Chinese medicine, 20(s)-Ginsenoside (GRh2), demonstrated an advancement in leukemia treatment.

A fast nucleic acid extraction system for point-of-care and integration of digital PCR.

Digital PCR is a powerful amplification method for absolute quantification of nucleic acids. The systems that integrated the nucleic acid extraction and amplification can reduce detection time, improve accuracy, and reduce labor costs. However, current nucleic acid extraction systems cannot be integrated well with integrated fluidic circuit (IFC) dPCR or droplet digital PCR chips perfectly and limit the application of digital PCR.

Investigation of the Presence of 22 Organochlorine Pesticide Residues in Ginseng from Jilin Province, China.

The purpose of this study was to investigate the status of organochlorine pesticide residues in 186 ginseng samples collected in Jilin, People's Republic of China. Based on the 2015 method for detection of organochlorine pesticide residues in ginseng, 22 organochlorine pesticide residues were identified. Chlordane, aldrin, epichlorohydrin, and dieldrin and their isomers were not detected in ginseng from this region.

Integrated microfluidic systems with sample preparation and nucleic acid amplification.

Rapid, efficient and accurate nucleic acid molecule detection is important in the screening of diseases and pathogens, yet remains a limiting factor at point of care (POC) treatment. Microfluidic systems are characterized by fast, integrated, miniaturized features which provide an effective platform for qualitative and quantitative detection of nucleic acid molecules. The nucleic acid detection process mainly includes sample preparation and target molecule amplification.

Proximity ligation assays for precise quantification of femtomolar proteins in single cells using self-priming microfluidic dPCR chip.

The quantification of low concentration proteins can facilitate the discovery of some significant biomarkers, and provide us a more profound understanding of cell heterogeneity when applied to single cell analysis. However, most state-of- art single cell protein detection platforms are bulky, expensive and complicated. Here we report a simple and low cost microfluidic dPCR (digital polymerase chain reaction) chip-based proximity ligation assay (PLA) for the quantification of low concentration proteins.

Power-free polydimethylsiloxane femtoliter-sized arrays for bead-based digital immunoassays.

A novel microfluidic chip employing power-free polydimethylsiloxane (PDMS) femtoliter-sized arrays was developed for the detection of low concentrations of protein biomakers by isolating individual paramagnetic beads in single wells. Arrays of femtoliter-sized wells were fabricated with PDMS using well-developed molding techniques. Paramagnetic beads were functionalized with specific antibodies to capture the antigens.

Study on a 65-mer peptide mimetic enzyme with GPx and SOD dual function.

Excessive reactive oxygen species (ROS) levels are harmful to the body. The peroxidase, GPx, and the superoxide dismutase, SOD, are important antioxidant enzymes for preventing ROS-induced damage. Se-CuZn-65P is an enzyme mimetic with dual GPx and SOD antioxidant function.