Immobilization of glucose oxidase on bioinspired polyphenol coatings as a high-throughput glucose assay platform.

Glucose oxidase (GOx) is an enzyme with important industrial and biochemical applications, particularly in glucose detection. Here we leveraged the oxidative self-polymerization phenomenon of simple polyphenols (pyrogallol or catechol) in the presence of polyethylenimine (PEI) to form adhesive coatings that enabled GOx immobilization on conventional multi-well plates. Immobilization was verified and optimized by directly measuring GOx activity inside the coated wells.

Polymethyl Methacrylate-Based Smart Microfluidic Point-of-Care Testing of Prothrombin Time and International Normalized Ratio through Optical Detection.

The mechanical heart valve is a crucial solution for many patients. However, it cannot function on the state of blood as human tissue valves. Thus, people with mechanical valves are put under anticoagulant therapy.

Isolation of enriched small RNA from cell-lysate using on-chip isotachophoresis.

In spite of the growing interest in the roles and applications of small RNAs (sRNAs), sRNA isolation methods are inconsistent, tedious, and dependent on the starting number of cells. In this work, we employ ITP to isolate sRNAs from the cell-lysate of K562 (chronic myelogenous leukemia) cells in a polydimethylsiloxane (PDMS) mesofluidic device. Our method specifically purifies sRNA of <60 nucleotides from lysate of a wide range of cell number spanning from 100 to 1 000 000 cells.

Microfluidics-based device for the measurement of blood viscosity and its modeling based on shear rate, temperature, and heparin concentration.

Blood viscosity measurements are crucial for the diagnosis and understanding of a range of hematological and cardiovascular diseases. Such measurements are heavily used in monitoring patients during and after surgeries, which necessitates the development of a highly accurate viscometer that uses a minimal amount of blood. In this work, we have designed and implemented a microfluidic device that was used to measure fluid viscosity with a high accuracy using less than 10 μl of blood.

Simultaneous RNA purification and size selection using on-chip isotachophoresis with an ionic spacer.

We present an on-chip method for the extraction of RNA within a specific size range from low-abundance samples. We use isotachophoresis (ITP) with an ionic spacer and a sieving matrix to enable size-selection with a high yield of RNA in the target size range. The spacer zone separates two concentrated ITP peaks, the first containing unwanted single nucleotides and the second focusing RNA of the target size range (2-35 nt).

Improvement of medical content in the curriculum of biomedical engineering based on assessment of students outcomes.

Background: Improvement of medical content in Biomedical Engineering curricula based on a qualitative assessment process or on a comparison with another high-standard program has been approached by a number of studies. However, the quantitative assessment tools have not been emphasized. The quantitative assessment tools can be more accurate and robust in cases of challenging multidisciplinary fields like that of Biomedical Engineering which includes biomedicine elements mixed with technology aspects.

Parkinson's disease hand tremor detection system for mobile application.

Parkinson's disease currently affects millions of people worldwide and is steadily increasing. Many symptoms are associated with this disease, including rest tremor, bradykinesia, stiffness or rigidity of the extremities and postural instability. No cure is currently available for Parkinson's disease patients; instead most medications are for treatment of symptoms.

Protein immobilization on the surface of polydimethylsiloxane and polymethyl methacrylate microfluidic devices.

PDMS and PMMA are two of the most used polymers in the fabrication of lab-on-chip or microfluidic devices. In order to use these polymers in biological applications, it is sometimes essential to be able to bind biomolecules such as proteins and DNA to the surface of these materials. In this work, we have evaluated a number of processes that have been developed to bind protein to PDMS surfaces which include passive adsorption, passive adsorption with glutaraldehyde cross-linking, (3-aminopropyl) triethoxysilane functionalization followed by glutaraldehyde or 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride cross-linkers.

Increasing the sensitivity of microfluidics based immunoassays using isotachophoresis.

We have developed a microfluidic device that enhances the sensitivity of protein immunoassays by preconcentrating the protein sample using isotachophoresis (ITP). Two approaches were followed to study the sensitivity gain achieved that way. The first approach was using antibody-coated magnetic beads loaded into a microchannel to capture the proteins within the ITP sample zone.

Cell-free protein synthesis in microfluidic 96-well plates.

Cell-free protein synthesis (CFPS) enables rapid protein expression for the structural and functional characterization of proteins. Implementation of CFPS in a microfluidic platform has additional benefits such as reduced reaction volumes and simultaneous expression of multiple proteins. Here, we describe a microfluidic device that is composed of 96 continuous-exchange cell-free protein expression units and produces a protein synthesis yield up to 87 times higher than a conventional batch system.

Stable, biocompatible lipid vesicle generation by solvent extraction-based droplet microfluidics.

In this paper, we present a microfluidic platform for the continuous generation of stable, monodisperse lipid vesicles 20-110 μm in diameter. Our approach utilizes a microfluidic flow-focusing droplet generation design to control the vesicle size by altering the system's fluid flow rates to generate vesicles with narrow size distribution. Double emulsions are first produced in consecutive flow-focusing channel geometries and lipid membranes are then formed through a controlled solvent extraction process.

Fabrication optimization of a miniaturized array device for cell-free protein synthesis.

Cell-free protein synthesis (CFPS) is an attractive alternative to cell-based protein expression systems because of its advantages including speed, simplicity, and adaptability to various formats. However, two major obstacles exist that have been preventing it from being widely used. One is high cost and the other is low protein synthesis yield.

Protein synthesis in a device with nanoporous membranes and microchannels.

Cell-free protein synthesis (CFPS) is an alternative approach to cell-based recombinant protein production. It involves in vitro transcription and translation in a cell-free medium. In this work, we implemented CFPS in a plastic array device.

Cell-free expression of soluble and membrane proteins in an array device for drug screening.

Enzymes and membrane protein receptors represent almost three-quarters of all current drug targets. As a result, it would be beneficial to have a platform to produce them in a high-throughput format for drug screening. We have developed a miniaturized fluid array device for cell-free protein synthesis, and the device was exploited to produce both soluble and membrane proteins.

Miniaturized fluid array for high-throughput protein expression.

We describe a miniaturized fluid array device for high-throughput cell-free protein synthesis (CFPS), aiming to match the throughput and scale of gene discovery. Current practice of using E. coli cells for production of recombinant proteins is difficult and cost-prohibitive to implement in a high-throughput format.

Cell-free protein expression in a microchannel array with passive pumping.

We report in vitro (cell-free) protein expression in a microfluidic device using passive pumping. The polystyrene device contains 192 microchannels, each of which is connected to two wells positioned in a 384-well microplate format. A larger droplet of an expression solution was placed at one well of each channel while a smaller droplet of a nutrient solution was at the other well.

Cell-free protein synthesis in microfluidic array devices.

We report the development of a microfluidic array device for continuous-exchange, cell-free protein synthesis. The advantages of protein expression in the microfluidic array include (1) the potential to achieve high-throughput protein expression, matching the throughput of gene discovery; (2) more than 2 orders of magnitude reduction in reagent consumption, decreasing the cost of protein synthesis; and (3) the possibility to integrate with detection for rapid protein analysis, eliminating the need to harvest proteins. The device consists of an array of units, and each unit can be used for production of an individual protein.