Functionalized Surface Coatings for Rigid Contact Lenses.

This research evolves into a comparative study of three different phenolic composites as coatings for rigid contact lenses, with a particular emphasis on enhancing their antifouling properties and hydrophobicity. The primary layer, comprised of diverse phenolic compounds, serves as a sturdy foundation. An exclusive secondary layer, featuring synthetic peptoids, is introduced to further minimize biofouling. Validated through X-ray photoelectron spectroscopy, the surface analysis confirms the successful integration of the polyphenolic layers and the subsequent grafting of peptoids onto the lens surface. The efficacy of the proposed coatings is substantiated through protein adsorption tests, providing definitive evidence of their antifouling capabilities. This research employs a nuanced assessment of coating performance, utilizing the quantification of fluorescence intensity to gauge effectiveness. Additionally, contact angle measurements offer insights into wettability and surface characteristics, contributing to a comprehensive understanding of the coating's practicality.

A Modular Strategy for Functional Pressure Sensitive Adhesives.

A modular approach to synthesizing functional pressure sensitive adhesives (PSAs) was introduced, wherein a modifiable acrylic PSA copolymer was synthesized by copolymerizing common PSA monomers with 6 mol % glycidyl methacrylate, allowing for subsequent functional group modification via the pendant epoxide functionality. This postmodification technique has the advantage of allowing the installation of a variety of functional groups relevant to adhesion, without variation of molecular weight. Because comparisons of cohesive and adhesive performance of candidate PSAs can be complicated by molecular weight differences, this strategy simplifies direct comparisons of the effects of functional groups on performance. As a proof of concept, a mussel-inspired catecholic PSA was synthesized by postreaction of the epoxide scaffold polymer with a thiol-modified catechol, allowing the effect of catechol on underlying structure-property relationships to be determined without variation in molecular weight. The mechanical performance of catecholic PSA was compared to relevant control PSAs by using industry-standard 180° peel and static shear tests, revealing an increase in peel strength achieved through catechol modification. Moreover, we observed an unexpected enhancement in PSA cohesive strength attributed to oxidation of catechol, which cannot be attributed to differences in molecular weight, a common source of changes in PSA cohesive strength.

Luminescent silicon nanoparticles for distinctive tracking of cellular targeting and trafficking.

Developing therapeutic nanoparticles that actively target disease cells or tissues by exploiting the binding specificity of receptors presented on the cell surface has extensively opened up biomedical applications for drug delivery and imaging. An ideal nanoparticle for biomedical applications is required to report confirmation of relevant targeting and the ultimate fate in a physiological environment for further verification, e.g. to adapt dosage or predict response. Herein, we demonstrate tracking of silicon nanoparticles through intrinsic photoluminescence (PL) during the course of cellular targeting and uptake. Time-resolved analysis of PL characteristics in cellular microenvironments provides dynamic information on the physiological conditions where the silicon nanoparticles are exposed. In particular, the PL lifetime of the silicon nanoparticles is in the order of microseconds, which is significantly longer than the nanosecond lifetimes exhibited by fluorescent molecules naturally presented in cells, thus allowing discrimination of the nanoparticles from the cellular background autofluorescence in time-gated imaging. The PL lifetime is a physically intensive property that reports the inherent characteristics of the nanoparticles regardless of surrounding noise. Furthermore, we investigate a unique means to inform the lifespan of the biodegradable silicon nanoparticles responsive to local microenvironment in the course of endocytosis. A multivalent strategy of nanoparticles for enhanced cell targeting is also demonstrated with complementary analysis of time-resolved PL emission imaging and fluorescence correlation spectroscopy. The result presents the promising potential of the photoluminescent silicon nanoparticles toward advanced cell targeting systems that simultaneously enable tracking of cellular trafficking and tissue microenvironment monitoring.

Biological Fixed Film.

The review includes literature published in the year of 2015 regarding the uses of biofilm in full-scale and lab-scale bioreactors to treat wastewater. The topics considered include biofilm formation and factors impacting biofilm formation; extracellular polymeric substance from biofilms; biofilm consortia and quorum sensing; biofilm reactors and biofilm in bioelectrochemical systems.