Graphical abstract A cellular protease-mediated graphene-based nanosystem is developed for co-delivery of a membrane-associated cytokine (TRAIL) and an intracellular-acting small-molecule drug (DOX). The nanocarrier realizes the intramembrane enzyme-mediated extracellular release of TRAIL and endocytotic acidity-responsive intracellular release of DOX, which enables them to target to their distinct sites of action. This formulation starts a new generation of 2D nanomaterials with programmed-release therapeutics capability for combination cancer treatment.

Many researchers have worked to develop methods to analyze and characterize capacity fade in lithium-ion batteries. As a complement to approaches to mathematically model capacity fade that require detailed understanding of each mechanism, capacity fade was accurately and efficiently predicted for future cycles using a discrete approach by extrapolating the change in effective transport and kinetic parameters with cycle number (N) for a battery tested under controlled experimental conditions. The effective parameters and their uncertainties are estimated using a mathematical reformulation of a porous electrode model, whose computational efficiency enables the integration of the proposed approach into an inexpensive microprocessor for estimating the remaining lifetime of a battery based on past charge-discharge curves. The approach may also provide some guidance for designers as to which battery components to focus on for redesign to reduce capacity fade.

SynopsisNanodiamonds (ND), i.e., sp 3 -hybridized nanoscale carbon particles, are being widely explored for biomedical applications, such as drug delivery and medical imaging, because of their biocompatibility, nontoxic nature, and ease of surface functionalization. However, little is known about the colloidal and rheological properties of ND dispersions. Here, we report a systematic study on NDs dispersed in a nonpolar liquid, mineral oil. We find that our smallest entities in dispersion are tightly bound aggregates ($400 nm) of individual primary ($5 nm) particles. These aggregates form colloidal gels (with frequency-independent moduli) at low particle concentrations ($5 wt. %). Gelation is likely due to attractive interparticle forces composed of both van der Waals and hydrogen-bonding interactions. The elastic modulus (G 0 ), yield stress (r y ), and yield strain (c 0 ) of these colloidal gels all show scaling relationships with ND concentration, with G 0 and r y exhibiting positive power-law exponents and c 0 showing a negative one. These results suggest a sample-spanning network of interconnected flocs, each of which is composed of several ND aggregates. Functionalization of ND surfaces with methacrylate groups eliminates gelation and gives a stable, low-viscosity dispersion. Much like other particulate gels, ND gels show thixotropic behavior, i.e., the gel network is disrupted by large deformations (steady or oscillatory shear) and is reformed upon cessation of shear. However, after oscillatory shear at a large strain-amplitude (1000%), the recovery is incomplete and the modulus of the recovered gel is only half its original value. In contrast, near-complete recovery of the modulus is observed after steady shear. V C 2014 The Society of Rheology. [http://dx.

A significant problem affecting electrospun nanofibrous tissue scaffolds is poor infiltration of cells into their three-dimensional (3D) structure. Environmental and physical manipulation, however, can enhance cellular infiltration into electrospun scaffolds. In this work, RGD-modified alginate mats with increased thickness and porosity were achieved by pairing high humidity electrospinning with post-processing ultra-sonication. RGD-modified alginate, polyethylene oxide (PEO), and an FDA-approved, nonionic surfactant blends were electrospun in 20 and 50% relative humidity conditions. Mats electrospun in high humidity conditions resulted in significantly increased mat thickness and decreased fiber diameters. The mats’ alginate content was then isolated via ionic crosslinking and PEO/surfactant extraction. Finally, the alginate-only mat was post-processed by ultra-sonication to further enhance its cross-sectional thickness. Cell morphology, proliferation, and infiltration into the scaffolds were evaluated by seeding fibroblasts onto the alginate mat. Cell spreading, growth and infiltration improved with increased humidity and ultra-sonication. This approach shows great promise for the design of cell-permeable nanofibrous scaffolds for tissue-engineering applications.

Cyclodextrin complexation of chitosan presents a novel route to achieve nanofibers of chitosan and other difficult-to-electrospin biopolymers.