1-Acetyl-β-Carboline from a Jeju Gotjawal Strain sp. JNUCC 0626 and Its Melanogenic Stimulating Activity in B16F10 Melanoma Cells.

The genus is a prolific source of bioactive and structurally diverse secondary metabolites. We isolated a novel strain, sp. JNUCC 0626, from Hwasun Gotjawal on Jeju Island, Korea.

Capillary force-driven reverse-Tesla valve structure for microfluidic bioassays.

Biological assays involve the lysis of biological particles, enzyme reactions, and gene amplification, and require a certain amount of time for completion. Microfluidic chips are regarded as powerful devices for biological assays and diagnostics; however, they cannot achieve a high mixing efficiency, particularly in some time-consuming biological reactions. Herein, we introduce a microfluidic reverse-Tesla (reTesla) valve structure in which the fluid is affected by vortices and branch flow convergence, resulting in flow retardation and a high degree of mixing.

Enhanced enrichment of collected airborne coronavirus and influenza virus samples via a ConA-coated microfluidic chip for PCR detection.

The severe acute respiratory syndrome (SARS-CoV-2) outbreak triggered global concern and emphasized the importance of virus monitoring. During a seasonal influenza A outbreak, relatively low concentrations of 10-10 viral genome copies are available per 1 m of air, which makes detection and monitoring very challenging because the limit of detection of most polymerase chain reaction (PCR) devices is approximately 10 viral genome copies/mL. In response to the urgent need for the rapid detection of airborne coronaviruses and influenza viruses, an electrostatic aerosol-to-hydrosol (ATH) sampler was combined with a concanavalin A (ConA)-coated high-throughput microfluidic chip.

E2E-BPF microscope: extended depth-of-field microscopy using learning-based implementation of binary phase filter and image deconvolution.

Several image-based biomedical diagnoses require high-resolution imaging capabilities at large spatial scales. However, conventional microscopes exhibit an inherent trade-off between depth-of-field (DoF) and spatial resolution, and thus require objects to be refocused at each lateral location, which is time consuming. Here, we present a computational imaging platform, termed E2E-BPF microscope, which enables large-area, high-resolution imaging of large-scale objects without serial refocusing.

Machine learning-powered electrochemical aptasensor for simultaneous monitoring of di(2-ethylhexyl) phthalate and bisphenol A in variable pH environments.

Plastic waste is a pernicious environmental pollutant that threatens ecosystems and human health by releasing contaminants including di(2-ethylhexyl) phthalate (DEHP) and bisphenol A (BPA). Therefore, a machine-learning (ML)-powered electrochemical aptasensor was developed in this study for simultaneously detecting DEHP and BPA in river waters, particularly to minimize the electrochemical signal errors caused by varying pH levels. The aptasensor leverages a straightforward and effective surface modification strategy featuring gold nanoflowers to achieve low detection limits for DEHP and BPA (0.

An all-in-one platform to deplete pathogenic bacteria for rapid and safe enrichment of plant-derived extracellular vesicles.

Plant-derived extracellular vesicles (PDEVs) have exhibited several advantages, such as high biocompatibility, improvement of skin conditions, and the prevention of skin aging. However, traditional methods of extraction for plant substances, such as heating under reflux or solvent extraction, are complicated, time-consuming, and low in purity. Accordingly, a simple and efficient platform is necessary for purely isolating natural substances from plants.

Modularized dynamic cell culture platform for efficient production of extracellular vesicles and sequential analysis.

Extracellular vesicles (EVs) are nanometer-sized particles naturally secreted by cells for intercellular communication that encapsulate bioactive cargo, such as proteins and RNA, with a lipid bilayer. Tumor cell-derived EVs (tdEVs) are particularly promising biomarkers for cancer research because their contents reflect the cell of origin. In most studies, tdEVs have been obtained from cancer cells cultured under static conditions, thus lacking the ability to recapitulate the microenvironment of cells .

Coil spring-powered pump with inertial microfluidic chip for size-based isolation and enrichment of biological cells.

Microfluidic chips have been widely used for diagnostics using pretreatment of biological samples; however, biologists and clinical researchers have difficulties using them in resource-limited settings. Sample injection systems for microfluidic chips are bulky, expensive, electricity-powered, and complex. A coiled spring-powered device, which can be used to isolate variously sized cells with high efficiency continuously and passively, was developed for portable, low-cost, electricity-free, and simple sample injection.

A modular microfluidic platform for serial enrichment and harvest of pure extracellular vesicles.

Extracellular vesicles (EVs) are recognized as promising biomarkers for several diseases. However, their conventional isolation methods have several drawbacks, such as poor yields, low purity, and time-consuming operations. Therefore, a simple, low-cost, and rapid microfluidic platform has been extensively developed to meet the requirement in biomedical applications.

Electrochemical biosensor for nucleic acid amplification-free and sensitive detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA via CRISPR/Cas13a trans-cleavage reaction.

The outbreak of the COVID-19 pandemic has led to millions of fatalities worldwide. For preventing epidemic transmission, rapid and accurate virus detection methods to early identify infected people are urgently needed in the current situation. Therefore, an electrochemical biosensor based on the trans-cleavage activity of CRISPR/Cas13a was developed in this study for rapid, sensitive, and nucleic-acid-amplification-free detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Multi-miRNA panel of tumor-derived extracellular vesicles as promising diagnostic biomarkers of early-stage breast cancer.

Extracellular vesicles (EV) have been emerging as potential biomarkers for disease monitoring. In particular, tumor-derived EV (TDE) are known to carry oncogenic miRNA, so they can be used for diagnosis of early cancer by analyzing the expression levels of EV-miRNA circulating in the blood. Here, using our novel microfluidic device, we rapidly and selectively isolate cancerous EV expressing breast cancer-derived surface markers CD49f and EpCAM within 2 minutes.

Microfluidic recapitulation of circulating tumor cell-neutrophil clusters double spiral channel-induced deterministic encapsulation.

Circulating tumor cell (CTC)-neutrophil clusters are highly potent precursors of cancer metastasis. However, their rarity in patients' blood has restricted research thus far, and moreover, studies on methods for mimicking cell clusters have generally neglected conditions. Here, we introduce an inertial-force-assisted droplet microfluidic chip that allows the recapitulation of CTC-neutrophil clusters in terms of physical as well as biochemical features.

Microfluidic chip for rapid and selective isolation of tumor-derived extracellular vesicles for early diagnosis and metastatic risk evaluation of breast cancer.

The epithelial-to-mesenchymal transition (EMT) index in cancer is a complementary approach for estimating metastatic risk. Considering the demand for evaluating metastatic risk based on liquid biopsies, tumor-derived extracellular vesicles (EVs) can be exploited to generate the EMT index. For the generation of EVs-based EMT index, it is essential to selectively isolate each epithelial cell and mesenchymal cell-derived EVs.

Detachable microfluidic device implemented with electrochemical aptasensor (DeMEA) for sequential analysis of cancerous exosomes.

The quantification of cancer-derived exosomes has a strong potential for minimally invasive diagnosis of cancer during its initial stage. As cancerous exosomes form a small fraction of all the exosomes present in blood, ultra-sensitive detection is a prerequisite for the development of exosome-based cancer diagnostics. Herein, a detachable microfluidic device implemented with an electrochemical aptasensor (DeMEA) is introduced for highly sensitive and in-situ quantification of cancerous exosomes.

Automatically Controlled Microfluidic System for Continuous Separation of Rare Bacteria from Blood.

Bloodstream infection by microorganisms is a major public health concern worldwide. Millions of people per year suffer from microbial infections, and current blood culture-based diagnostic methods are time-consuming because of the low concentration of infectious microorganisms in the bloodstream. In this study, we introduce an efficient automated microfluidic system for the continuous isolation of rare infectious bacteria (Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa) from blood.

Progress in Circulating Tumor Cell Research Using Microfluidic Devices.

Circulating tumor cells (CTCs) are a popular topic in cancer research because they can be obtained by liquid biopsy, a minimally invasive procedure with more sample accessibility than tissue biopsy, to monitor a patient's condition. Over the past decades, CTC research has covered a wide variety of topics such as enumeration, profiling, and correlation between CTC number and patient overall survival. It is important to isolate and enrich CTCs before performing CTC analysis because CTCs in the blood stream are very rare (0⁻10 CTCs/mL of blood).

A microfluidic electrochemical aptasensor for enrichment and detection of bisphenol A.

Bisphenol A (BPA) is an organic monomer used to make common consumer goods such as plastic containers, sports equipment, and cosmetics which are heavily produced worldwide. A growing interest has been drawn to general public as BPA is one of the major endocrine disrupting chemicals threating human health. To date, numerous BPA sensors have been attempted to be developed but important challenges still remained such as limited linearity range, easy to use, and long term response time.