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Highlights: [•] Millifluidic reactor can be used to prepare cross-linked cellulase aggregate (XCA). [•] The XCA has a very uniform size distribution between 200nm and 400nm. [•] Flow rates and mixing patterns can be precisely controlled. [•] It is possible to control the particle size of the XCA. [•] It shows excellent thermal stability, and can be reused for several cycles. [Copyright &y& Elsevier]

Highlights: [•] Hybrid cellulase aggregate consists of cross-linked cellulase layers physically adsorbed on silica gel. [•] Higher glucose production than cross-linked cellulase aggregates without silica core. [•] Reusable for cellulose and biomass hydrolysis. [Copyright &y& Elsevier]

Abstract: Materials with chemical micropatterned surface have broad applications in many fields. In this article, we report a simple one-step UV lithography method to activate inert hydrocarbon monolayers for spontaneous formation of water and covalently immobilized protein micropatterns on the surface. Two types of hydrocarbon monolayers including octadecyltrichlorosilane (OTS) on silicon oxide and 1-hexadecene on hydrogen-terminated silicon were studied. It was found that after UV modifications, water can form micropatterns spontaneously on both surfaces. Furthermore, when protein solutions were used, covalently immobilized protein micropatterns can be formed. Our XPS results and controlled reducing experiments showed that UV exposure transformed inert monolayers into active surfaces with aldehyde groups, which are responsible for the covalent immobilization of proteins. The method reported herein can be applied under ambient conditions without having a high vacuum system. It can also be extended to pattern other biomolecules bearing amine groups. [Copyright &y& Elsevier]

Electrosorption is generally defined as potential-induced adsorption on the surface of charged electrodes. After polarization of the electrodes, ions are removed from the electrolyte solution by the imposed electric field and adsorbed onto the surface of the electrodes. Experimental and modeling studies were conducted using two types of carbon aerogel composites of different surface areas to provide a better understanding on the mechanisms of electrosorption. The experimental results revealed that no significant specific adsorption of F− ions occurred, while strong specific adsorption was observed for NO3− and Cu2+ ions. In addition, although the two types of carbon aerogel electrodes had different surface areas, their capacities were found to be very similar because of the electrical double-layer overlapping effect in micropores. An electrical double-layer model developed in our previous work (16), in which the electrical double-layer overlapping correction is included, is expanded in the present work by considering the effect of the specific adsorption on the electrosorption process. Modeling results were compared with experimental data obtained under various conditions. When the overlapping effect and specific adsorption were considered, the model provided results that were in good agreement with experimental data. [Copyright &y& Elsevier]

Abstract: In this paper, we report a method of printing uniform protein lines on glass slides by using UV-treated flat PDMS stamps. Unlike traditional microcontact printing (μCP) which requires microstructured PDMS stamps, this μCP method only requires a flat PDMS stamp, an UV lamp and a number of straight needles. Our results show that lines of bovine serum albumin (BSA), immunoglobin (IgG), anti-biotin, anti-human IgG and anti-mouse IgG can be printed evenly on glass slides by using this μCP method. We also demonstrate that the printed protein lines are suitable for applications such as microfluidic immunoassays. [ABSTRACT FROM AUTHOR]

Abstract: We describe a high throughput method of printing DNA submicron patterns on solid substrates. Combining nanoimprint lithography and contact printing, uniform DNA patterns can be produced with feature sizes from 2 μm down to 250 nm. In this method, poly(methylmethacrylate) (PMMA) with submicron line or dot patterns (produced by nanoimprint lithography) is first chemically functionalized with poly(ethyleneimine) (PEI) to aminate the surface and then a DNA pattern is prepared on the surface. PEI modification leads to higher DNA immobilization and DNA hybridization efficiency due to a higher density of amine functional groups provided by PEI. Next, complementary target DNA hybridized to the PMMA surface can be transferred to an aminated glass slide through contact printing. The transfer mechanism is due to electrostatic attraction (between DNA and amine groups) which can overcome hydrogen bonds between two hybridized DNA molecules. DNA transferred from the PMMA to the glass slide still can hybridize with DNA having a complementary sequence. This method provides a facile and high throughput means of preparing uniform DNA submicron patterns which are difficult to prepare by using conventional solution-based methods. [Copyright &y& Elsevier]