Dynamic Liver Chip Based on Well-Coupled Microfluidics: An Accurate NASH Model for Drug Evaluation.

The convenient liver model in vitro recapitulating the hepatic functions, metabolism, and even steatohepatitis to perform the accurate drug evaluation is still challenging because of the unattainable hominine physiological microenvironment in vitro. Here, the progressed stages of nonalcoholic steatohepatitis (NASH) disease were precisely modeled to accurately evaluate the performance of antilipemic based on the dynamic liver chip adopting the well-coupled microfluidics, which well recapitulated the normal and steatohepatitis of liver in vitro. In brief, the mild nutrient flow and sufficient oxygen supply for parenchymal liver cells could be well supplied through the endothelial cells layer that mimicked the real physiological barrier of endothelium, while the loading of drugs might be obtained by directly adding drug into the running nutrient flow to mimic the intravenously administrable.

A rat model of cerebral small vascular disease induced by ultrasound and protoporphyrin.

Cerebral small vascular disease (CSVD) has a high incidence worldwide, but its pathological mechanisms remain poorly understood due to the lack of proper animal models. The current animal models of CSVD have several limitations such as high mortality rates and large-sized lesions, and thus it is urgent to develop new animal models of CSVD. Ultrasound can activate protoporphyrin to produce reactive oxygen species in a liquid environment.

Microsphere-Enhanced Fluorescence-Lightened Solid-Phase Hybridization Assay: The Strategy to Highly Selective Detection of Micro Ribonucleic Acids.

The detection of low-abundance microribonucleic acid (miRNA) frequently adopted nucleic acid sequence-based amplification detection, which was found to have poor selectivity for the nonspecific amplification of template-dependent ligation in enzyme-mediated cascade reactions. Here, a highly selective detection of miRNAs was developed that combined microsphere-enhanced fluorescence (MSEF) and solid-phase base-paired hybridization. The target miRNA could be accurately and quantitatively identified through the solid-phase hybridization assay on the surface of an optical microsphere, while the detected fluorescence signal could be physically amplified by MSEF.

Dynamic tissue model in vitro and its application for assessment of microplastics-induced toxicity to air-blood barrier (ABB).

The replication of the hominine physiological environment was identified as an effectual strategy to develop the physiological model in vitro to perform the intuitionistic assessment of toxicity of contaminations. Herein, we proposed a dynamic interface strategy that accurately mimicked the blood flow and shear stress in human capillaries to subtly evaluate the physiological damages. To proof the concept, the dynamic air-blood barrier (ABB) model in vitro was developed by the dynamic interface strategy and was utilized to assess the toxicity of polyethylene terephthalate microplastics (PET-MPs).

Microsphere amplified fluorescence and its application in sensing.

The far-field fluorescence amplification, the intense fluorescence emission addresses the great potential in sensitive detection to large biomolecules, was seriously ignored for the failure in amplifying the weak fluorescence excepting the electromagnetic field (EM) induced fluorescence amplification on the metallic surfaces. Here, a microsphere in hundreds of micrometers was adopted to proceed with the fluorescence amplification via building up a local dielectric surrounding for fluorophore. The wide range of contribution-angle fluorescence could be efficiently restricted within the microsphere by facilitating the energy of reflection restraining and declining the energy of refraction decaying and the intense fluorescence emission confined within the microsphere could be directly observed.

Localized hydrodynamic flow confinement assisted nanowire sensor for ultrasensitive protein detection.

Affordable methods for ultra-sensitive biomarkers detection may improve the standard of living in resource-constrained countries. Nanowire biosensor is preponderant in ultra-sensitive protein detection. However, current strategies for nanowire sensor (NWS) fabrication often require sophisticated instruments, being inaccessible in less-resourced laboratories.

Selective Fabrication of Nanowires with High Aspect Ratios Using a Diffusion Mixing Reaction System for Applications in Temperature Sensing.

The selective fabrication of highly ordered nanowires with high aspect ratios was of low reproducibility, which remains a challenge for laboratory research. In this paper, we report a novel approach for selective fabrication of conductive nanowires on a solid surface via diffusion mixing reaction system formed by a chemical pen. The nanoscale-mixing region was achieved by appropriately adjusting the viscosity of the solution and other parameters with the aid of dyes functioned as a flow boundary indicator.

Droplet Sensitized Fluorescence Detection for Enzyme-Linked Immune Sorbent Assays on Microwell Plate.

The microwell plate/microtiter plate is among the most widely used tools in immune assays. In this paper, we report on a sensitive method for enhancing fluorescence emission detection by simply adding several droplets of an immiscible organic compound into the microwells before detection. To prove the concept, human IgA was determined on a microwell plate using this droplet enhanced fluorescence (DEF) detection method.

Reversibly Switching Molecular Spectra.

Manipulation of light transmission/absorbance and reflection/emission has a great significance in smart windows and displaying media like liquid crystal. Here, we report the usage of an external electric field to reversibly switch the molecular spectra of a model molecule on the basis of its interaction with an electroresponsible polymer brush. Both the UV-vis absorbance spectrum and the fluorescence emission spectrum of the model molecule were confirmed to be electroswitchable.

Inkjet Printing Based Droplet Generation for Integrated Online Digital Polymerase Chain Reaction.

We report on the development of a novel and flexible online digital polymerase chain reaction (dPCR) system. The system was composed of three parts: an inkjet for generating the droplets, a coiled fused-silica capillary for thermal cycling, and a laser-induced fluorescence detector (LIFD) for positive droplet counting. Upon inkjet printing, monodisperse droplets were continuously generated in the oil phase and then introduced into the capillary in the form of a stable dispersion.

Elaborately programmed nanowires fabricated using a tapered push-pull nozzle system.

Elaborately programmed silver nanowire arrays can be prepared using a tapered push-pull nozzle system (TPPNS), which is used to directly write micro-nano wires on a substrate via a two-reagent reaction in the diffusion mixing region. The wires could be precisely positioned on the substrate and their width could be freely controlled from the micro to the nano scale, indicating an advance in the methodologies of controlling and fabricating nanowires. The as-prepared silver three-electrode device can serve as a three-electrode sensor.

Inkjet Printing Based Separation of Mammalian Cells by Capillary Electrophoresis.

This study describes a method to investigate the separation of cells by capillary electrophoresis (CE) coupled with inkjet printing system. The results validated the feasibility of inkjet printing for mammalian cells to achieve the drop-on-demand and convenient sampling into capillary then zone electrophoresis was applied to separate different cells according to their electrophoretic mobility, finally the peak signal were measured by UV detector. Linear relationship between the peak area and the droplet number was obtained within the range of 25-400 drops (R = 0.

Convection-Diffusion Layer in an "Open Space" for Local Surface Treatment and Microfabrication using a Four-Aperture Microchemical Pen.

A four-aperture microchemical pen was used to produce a stable convection-diffusion layer in an "open space" for microreactions and microfabrication. The process represents a new method for microreactions and microfabrication in a convection-diffusion layer. To prove the concept of a convection-diffusion layer in an "open space", bovine serum albumin was labeled with 4-fluoro-7-nitro-2,1,3-benzoxadiazole to confirm that the small convection-diffusion layer was effective for local surface treatment.

The use of an inkjet injection technique in immunoassays by quantitative on-line electrophoretically mediated microanalysis.

The paper describes a new online quantitative electrophoretically mediated microanalysis (EMMA) for use in immunoassays based on the unique drop-by-drop introduction of a sample by means of an inkjet for capillary electrophoresis (CE). Plugs of a fluorescein-labeled antibody (Anti-humanIgG-DyL550) and human IgG were alternately injected into a capillary using the inkjet, followed by the merging of the plugs and the subsequent immune reaction. The antigen-antibody complex that was formed in the merged zone was then separated by CE.

Microchemical Pen: An Open Microreactor for Region-Selective Surface Modification.

Various micro surface-modification approaches including photolithography, dip-pen lithography and ink-jet systems have been developed and used to extend the functionalities of solid surfaces. While those approaches work in the "open space", push-pull systems which work in solutions have recently drawn considerable attention. However, the confining flows performed by push-pull systems have realized only the dispense process, while microscale, region-selective chemical reactions have remained unattainable.

Inkjet printing based assembly of thermoresponsive core-shell polymer microcapsules for controlled drug release.

A controlled drug delivery system (DDS) was designed by integrating the thermoresponsive copolymer poly(N-isopropylacrylamide-co-methacrylic acid) (poly(NIPAAm-co-MAA)) with core-shell 1,6-hexanediol diacrylate (HDDA) microparticles. The monodisperse HDDA particles with a hollow core and a nanoporous shell were fabricated in a continuous manner by an initially proposed inkjet printing process combined with UV polymerization. The thermoresponsive poly(NIPAAm-co-MAA) copolymer was grafted onto the surface of HDDA microcapsules by free radical initiated polymerization.

Droplet Enhanced Fluorescence for Ultrasensitive Detection Using Inkjet.

A fluorescence enhanced phenomenon was found within a micrometer-sized liquid droplet, and it was adopted to construct droplet enhanced fluorescence (DEF) for ultrasensitive fluorescence detection. In this paper, an inkjet was utilized to eject perfect spherical droplets to construct a microspherical resonator and to develop a DEF system. It was utilized to implement ultrasensitive fluorescence detection in a liquid specimen with a volume of several microliters.

Microchip with an open tubular immobilized ph gradient for UV whole column imaging detection.

This study reports a new method for establishing an open tubular IPG in a microchip coupled with a whole column image detection (WCID) system for protein separation applications. This method allows a wider range of immobilized pH (2.6-9.

Quantitative on-line concentration for capillary electrophoresis with inkjet sample introduction technique.

A quantitative sample introduction method based upon inkjet injection was applied to capillary electrophoresis coupled with stacking and sweeping on-line concentration techniques. Methylxanthines were used as model compounds for the proof-of-concept of the method. The volume of injected sample could be easily manipulated by controlling the number of ejected droplets in the injection procedure.

Drop-by-drop chemical reaction and sample introduction for capillary electrophoresis.

In this paper, we report a novel sample introduction and chemical reaction strategy by drop-by-drop inkjet injection for an electrophoretically mediated microanalysis (EMMA). This method makes it possible to achieve an on-line introduction of reactant solutions by alternately ejecting small plugs, with an overlapping region of the plugs for mixing the reactants by electrophoresis, supporting chemical reactions, followed by electrophoretic separation of the final compounds. As a proof-of-concept of the method, the EMMA of an inkjetted mixture of 4-fluoro-7-nitrobenzofurazan (NBD-F) and amino acids was carried out as a model chemical reaction.

A chemo-mechanical switch for controllable water transportation based on a thermally responsive block copolymer.

A smart and reversible chemo-mechanical switch was developed by synthesis of a thermally responsive block copolymer brush poly(N-isopropylacrylamide-co-hexafluoroisopropyl acrylate) (P(NIPAAm-co-HFIPA)) on a capillary plate. With the temperature changing around lower critical solution temperature (LCST), the designed chemo-mechanical switch exhibited excellent "ON-OFF" behavior for water transportation.

A compact immunoassay platform based on a multicapillary glass plate.

A highly sensitive, rapid immunoassay performed in the multi-channels of a micro-well array consisting of a multicapillary glass plate (MCP) and a polydimethylsiloxane (PDMS) slide is described. The micro-dimensions and large surface area of the MCP permitted the diffusion distance to be decreased and the reaction efficiency to be increased. To confirm the concept of the method, human immunoglobulin A (h-IgA) was measured using both the proposed immunoassay system and the traditional 96-well plate method.

Inkjet nanoinjection for high-thoughput chemiluminescence immunoassay on multicapillary glass plate.

We report a novel chemiluminescence diagnosis system for high-throughput human IgA detection by inkjet nanoinjection on a multicapillary glass plate. As proof-of-concept, microhole-based polydimethylsiloxane (PDMS) sheets were aligned on a multicapillary glass plate to form a microwell array as microreactors for enzyme-linked immunosorbent assay (ELISA). The multicapillary glass plate was utilized as a switch that controlled the holding/passing of the solution.

A piezoelectric drop-on-demand generator for accurate samples in capillary electrophoresis.

In this work, we propose a piezoelectric droplet generator for injection of well-defined amounts of sample in capillary electrophoresis. We demonstrate stable, precise and drop-on-demand droplet formation for various solutions, with precise control of waveform driving piezoelectric crystal inside the ink-jet head. By tuning the waveform, we can also manipulate the droplet size and delivery frequency.

Development of a novel two dimensional surface plasmon resonance sensor using multiplied beam splitting optics.

A novel two dimensional surface plasmon resonance (SPR) sensor system with a multi-point sensing region is described. The use of multiplied beam splitting optics, as a core technology, permitted multi-point sensing to be achieved. This system was capable of simultaneously measuring nine sensing points.