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A highly environmentally-friendly ubiquinone 10 (UQ10) based I2-free electrolyte, which is inspired by photosynthesis, is employed in dye-sensitized solar cells (DSSCs) under 100 mW cm-2 (AM 1.5G) illumination. Profiting from this UQ10 based electrolyte a 10% increased power conversion efficiency of 8.18% is achieved compared with the traditional one containing I2 (7.44%). The superior performance of this UQ10 based electrolyte is mainly derived from the lower visible light wastage and high catalytic activity to the counter electrode as revealed by photoelectrochemical characterization. Moreover, being widely adopted in cardiovascular medicine and cosmetics, UQ10 is a very safe and low-cost choice for DSSCs. With the advantages of high power conversion efficiency, bio-safety, universal dye compatibility and diversity of molecular design, UQ10 is very promising to be widely applied in DSSCs, and perovskite based solar cells. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate a new type of microfluidic chip that can realize continuous-flow purification of hydrogel beads from a carrier oil into aqueous solution by using a laminar-like oil/water interface. The microfluidic chip is composed by two functional components: (1) a flow-focusing bead generation module that can control size and shape of beads, (2) a bead extraction module capable of purifying hydrogel beads from oil into aqueous solution. This module is featured with large branch channels on one side and small ones on the opposite side. Water is continuously infused into the bead extraction module through the large branch channels, resulting in a laminar-like oil/water interface between the branch junctions. Simulation and experimental data show that the efficiency of oil depletion is determined by the relative flow rates between infused water and carrier oil. By using such a microfluidic device, viable cells (HCT116, colon cancer cell line) can be encapsulated in the hydrogel beads and purified into a cell culture media. Significantly improved cell viability was achieved compared to that observed by conventional bead purification approaches. This facile microfluidic chip could be a promising candidate for sample treatment in lab-on-a-chip applications. [ABSTRACT FROM AUTHOR]

In this paper we describe a versatile microfluidic strategy for simultaneous preparation of quantum dot-encoded microbeads with controllable barcodes. This method involves the generation of multiple dispersed solutions carrying stepwise concentration gradients of quantum dots by using a pyramidal microfluidic network, the formation of corresponding droplets in parallel flow-focusing droplet generators, and on-chip solidification of these droplets into microbeads. Using a designed microfluidic device, we simultaneously generated five kinds of fluorescence-encoded alginate hydrogel microbeads with a five-level stepwise concentration gradient of monochromatic quantum dot or five controllable ratios of two different-sized quantum dots. This method has the following features: (1) the barcode adapter compartment substitutes the respective preparation of precursor solutions containing the correct concentrations and ratios of different quantum dots for corresponding barcodes. (2) Identical microbeads with distinct quantum dot barcodes can be simultaneously generated in homogeneous conditions. (3) The microfluidic device can be upgraded by increasing or decreasing the inlets and outlets of the pyramidal network and the number of the parallel flow-focusing droplet generators to meet the requirements for the particular barcodes. We expect that this microfluidic route will facilitate the construction and mass-production of robust and reproducible barcode materials. [ABSTRACT FROM AUTHOR]

Optical barcoding technology based on quantum dot (QD)-encoded microparticles has attracted increasing attention in high-throughput multiplexed biological assays, which is realized by embedding different-sized QDs into polymeric matrixes at precisely controlled ratios. Considering the advantage of droplet-based microfluidics, producing monodisperse particles with precise control over the size, shape and composition, we present a proof-of-concept approach for on-demand preparation of QD-encoded microparticles based on this versatile new strategy. Combining a flow-focusing microchannel with a double T-junction in a microfluidic chip, biocompatible QD-doped microparticles were constructed by shearing sodium alginate solution into microdroplets and on-chip gelating these droplets into a hydrogel matrix to encapsulate CdSe/ZnS QDs. Size-controllable QD-doped hydrogel microparticles were produced under the optimum flow conditions, and their fluorescent properties were investigated. A novel multiplex optical encoding strategy was realized by loading different sized QDs into a single droplet (and thus a hydrogel microparticle) with different concentrations, which was triggered by tuning the flow rates of the sodium alginate solutions entrapped with different-colored QDs. A series of QD-encoded microparticles were controllably, and continuously, produced in a single step with the present approach. Their application in a model immunoassay demonstrated the potential practicability of QD-encoded hydrogel microparticles in multiplexed biomolecular detection. This simple and robust strategy should be further improved and practically used in making barcode microparticles with various polymer matrixes. [ABSTRACT FROM AUTHOR]