Hsiang-Yu Wang

National Tsing Hua University | NTHU · Department of Engineering and System Science

Background Single-cell droplet microfluidics is an important platform for high-throughput analyses and screening because it provides an independent and compartmentalized microenvironment for reaction or cultivation by coencapsulating individual cells with various molecules in monodisperse microdroplets. In combination with microbial biosensors, thi...

Cell surface properties of microorganisms provide abundant information for their physiological status and fate choice. However, current methods for analyzing cell surface properties require labeling or fixation, which can alter the cell activity. This study establishes a label-free, rapid, noninvasive, and quantitative analysis of cell surface prop...

Background Screen-printed sensors can be easily fabricated and have advantages of cost-effectiveness, low instrument demand, and decentralized fabrication. However, they often suffered from low reproducibility and conductivity, restraining them from practical applications. Method This study demonstrated a high-performance sensor with large surface...

The highly effective removal of multiple kinds of microplastics (MP) by microalgae Scenedesmus abundans was accomplished and the main mechanism of the MP removal was identified as hetero-aggregation. The accurate quantification of removal efficiency was achieved by quantifying free suspended microparticles before and after microalgae treatment. Sce...

Photosynthetic microalgae not only perform fixation of carbon dioxide but also produce valuable byproducts such as lipids and pigments. However, due to the lack of effective tools for rapid and noninvasive analysis of microalgal cellular contents, the efficiency of strain screening and culture optimizing is usually quite low. This study applied sin...

This study aims to investigate the efficacy of lipid induction in Scenedesmus abundans by adding the effluent from dark fermentation of biohydrogen production. Four sets of experiments were conducted: control (sufficient nitrogen), nitrogen depletion, low concentration (0.3×) effluent addition, and high concentration (0.5×) effluent addition. The a...

A key challenge for bioprocess engineering is the identification of the optimum process conditions for the production of biochemical and biopharmaceutical compounds using prokaryotic as well as eukaryotic cell factories. Shake flasks and bench‐scale bioreactor systems are still the golden standard in the early stage of bioprocess development, thoug...

Microbial fuel cells (MFCs) harvest electrons from microorganisms in the anode and perform reductive reactions, such as the reduction of oxygen into water, in the cathode. Efficient electron harvesting is important in constructing high-performance MFCs; however, current methods for evaluating Coulombic efficiency (CE) consume large amounts of time,...

Abstract This review presents a critical assessment of emerging microfluidic technologies for the application on biological productions of biofuels and other chemicals from microalgae. Comparisons of cell culture designs for the screening of microalgae strains and growth conditions are provided with three categories: mechanical traps, droplets, or...

This study demonstrates the electrorotation of single microalgae cells captured in the center of a set of planar microelectrodes within a microfluidic device, and compares the rotational speeds of single microalgae cells obtained in experiments and theoretical calculations. Negative dielectrophoresis force and rotational electric field are generate...

This study experimentally investigates the generation of polyelectrolyte droplets, and subsequently, cured microcarriers for application in microorganism cultivation. Microcarriers containing an mature microorganism culture can replace in situbiofilms in microfluidic bioprocesses to reduce the startup duration and facilitate the replenishment of fu...

The widely distributed genus Shewanella is famous for its capacity of electron transferring and extracellular polymeric substance (EPS) production. Regarding to the EPS production by Shewanella is a critical event for its application, the aim of this study is to decipher the effect of calcium ion on a new S. xiamenensis BC01 (SXM). It grew and surv...

Microbial fuel cell (MFC) is developed as a renewable energy source, which can simultaneously carries out wastewater treatment. The ability of microorganism in generating extractable electricity highly affects the performance of a MFC; therefore, it is critical to construct a high throughput analysis platform for microorganism screening. Microfluid...

A rapid quantification method for lipids and carotenoids in Chlorella vulgaris is demonstrated in this study. The rapid quantification translates Raman signal intensities into abundances of lipids and carotenoids via calibration curves established by gravimetric method (lipids) and UV spectrometry (carotenoids). The Raman signal intensities and the...

Microfluidic systems based on fluorescence detection have been developed and applied for many biological and chemical applications. Because of the tiny amount of sample in the system; the induced fluorescence can be weak. Therefore, most microfluidic systems deploy multiple optical components or sophisticated equipment to enhance the efficiency of...

Microalgae have emerged as one of the most promising feedstocks for biofuels and bio-based chemical production. However, due to the lack of effective tools enabling rapid and high-throughput analysis of the content of microalgae biomass, the efficiency of screening and identification of microalgae with desired functional components from the natural...

Chlorella vulgaris ESP-31 containing 22.7% lipid was harvested by coagulation (using chitosan and polyaluminium chloride (PACl) as the coagulants) and centrifugation. The harvested ESP-31 was directly employed as the oil source for biodiesel production via transesterification catalyzed by immobilized Burkholderia lipase and by a synthesized solid c...

This work presents the experimental analysis of heat transfer in a straight polydimethylsiloxane microchannel with cross-sectional width/depth ratio of 8.47 using the temperature-sensitive paint (TSP) technique. The TSP technique is capable of acquiring temperature profiles for both the surface and the fluid with a detailed resolution of 144 µm per...

A membraneless microfluidic microbial fuel cell (μMFC) for rapid detection of microorganism electroactivity is demonstrated in this study. Owing to the merit of laminar flow, the proposed μMFC has well-separated anode and cathode without applying proton exchange membrane. The highest open circuit voltages (OCVs) produced by different anodal solutio...

A rapid and noninvasive quantification method for cellular lipids in Chlorella vulgaris is demonstrated in this study. This method applied near-infrared Raman spectroscopy to monitor the change of signal intensities at 1440 cm(-1) and 2845-3107 cm(-1) along the nitrogen depletion period and calibration curves relating signal intensity and cellular...

Reducing the fluorescence background in microfluidic assays is important in obtaining accurate outcomes and enhancing the quality of detections. This study demonstrates an integrated process including cell labelling, fluorescence background reduction, and biomolecule detection using liquid-liquid extraction in a microfluidic droplet system. The cel...

This review presents the development of micro-sized microbial fuel cells (including mL-scale and μL-scale setups), with summarization of their advantageous characteristics, fabrication methods, performances, potential applications and possible future directions. The performance of microbial fuel cells (MFCs) is affected by issues such as mass trans...

Genetic modification of cells is a critical step involved in many cell therapy and gene therapy protocols. In these applications, cell samples of large volume (10(8)-10(9)cells) are often processed for transfection. This poses new challenges for current transfection methods and practices. Here we present a novel flow-through electroporation method...

IntroductionFlow-through Electroporation under Constant VoltageElectroporative Flow Cytometry for Detecting Protein TranslocationElectroporative Flow Cytometry for Measuring Single-cell BiomechanicsElectroporative Flow Cytometry for Selectively Releasing and Analyzing Specific Intracellular MoleculesConclusions AcknowledgmentsReferences

Microchip CE of proteins labeled either off- or on-chip with the "chameleon" CE dye 503 using poly(methyl methacrylate) microchips is presented. A simple dynamic coating using the cationic surfactant CTAB prevented nonspecific adsorption of protein and dye to the channel walls. The labeling reactions for both off- and on-chip labeling proceeded at...

Genetically modified cells with enhanced functions have emerged as promising materials in cell-based therapies such as cancer immunotherapy, stem cell therapy and tissue regeneration. In these applications, cell samples of large volume (108-109 cells) are often processed for transfection. This poses new challenges for current transfection methods a...

Detection and accurate quantitation of biomarkers such as alpha-fetoprotein (AFP) can be a key aspect of early stage cancer diagnosis. Microfluidic devices provide attractive analysis capabilities, including low sample and reagent consumption, as well as short assay times. However, to date microfluidic analyzers have relied almost exclusively on ca...

Microfluidic arrays of living cells have raised a lot of interests recently due to their potential for high throughput screening of cell-based assays. This report presents a microfluidic cell array with individually addressable chambers controlled by pneumatic valves for cell culture and treatment. There are two modes for the cell array to be opera...

Electroporation is an efficient method of introducing foreign impermeant molecules such as drugs and genes into cells. Conventional electroporation has been based on the application of short electrical pulses (electropulsation). Electropulsation requires specialized equipment and cannot be integrated easily with techniques such as electrophoresis w...

Microfluidics-based cell assays offer high levels of automation and integration, and allow multiple assays to be run in parallel, based on reduced sample volumes. These characteristics make them attractive for studies associated with drug discovery. Controlled delivery of drug molecules or other exogenous materials into cells is a critical issue th...

Directed localization of kinases within cells is important for their activation and involvement in signal transduction. Detection of these events has been largely carried out based on imaging of a low number of cells and subcellular fractionation/Western blotting. These conventional techniques either lack the high throughput desired for probing an...

Electrical lysis of biological cells on a microfluidic platform has evoked significant interest because of its applications in rapid recovery of intracellular contents such as nucleic acids or proteins without introducing lytic agents. Applying a direct current (DC) field for cell lysis typically requires field strength of 1-10 kV/cm, which is depe...

Interest in electrical lysis of biological cells on a microfludic platform has increased because it allows for the rapid recovery of intracellular contents without introducing lytic agents. In this study we demonstrated a simple microfluidic flow-through device which lysed Escherichia coli cells under a continuous dc voltage. The E. coli cells had...

Electroporation has been widely accepted as an important tool for the delivery of exogenous molecules into cells. Previous mechanistic studies have been carried out by observing either the average behavior from a large population of cells or the response from a small number of single cells. In this study, we demonstrated a novel microfluidic method...

A simple microfluidic device was demonstrated to analyze intracellular contents from single cells with high throughput based on having different field strengths in geometrically defined sections of a microchannel for electrical lysis and electrophoresis.

Electroporation has been widely used to load impermeant exogenous molecules into cells. Rapid electrical lysis based on electroporation has also been applied to analyze intracellular materials at single-cell level. There has been increasing demand to implement electroporation in a microfluidic format as a basic tool for applications ranging from sc...

Electrical lysis of biological cells on a microfluidic platform has been raising a lot of interests due to its applications in rapid recovering intracellular contents without introducing lytic agents. In this study, we demonstrated a simple microfluidic device which lysed green fluorescent protein (GFP) expressing E. coli cells under continuous DC...

In this thesis, I present two novel microfluidic techniques for cell-based high throughput analysis: flow-through electroporation and micro-bioreactor arrays. This thesis falls into two main parts. Part I (chapter 2 to 7) demonstrates the electroporative technique and part II (chapter 8 to 9) presents the micro-bioreactor array with individually ad...