3 research outputs found
Bio-Inspired Synthetic Nanovesicles for Glucose-Responsive Release of Insulin
A new glucose-responsive formulation
for self-regulated insulin
delivery was constructed by packing insulin, glucose-specific enzymes
into pH-sensitive polymersome-based nanovesicles assembled by a diblock
copolymer. Glucose can passively transport across the bilayer membrane
of the nanovesicle and be oxidized into gluconic acid by glucose oxidase,
thereby causing a decrease in local pH. The acidic microenvironment
causes the hydrolysis of the pH sensitive nanovesicle that in turn
triggers the release of insulin in a glucose responsive fashion. In
vitro studies validated that the release of insulin from nanovesicle
was effectively correlated with the external glucose concentration.
In vivo experiments, in which diabetic mice were subcutaneously administered
with the nanovesicles, demonstrate that a single injection of the
developed nanovesicle facilitated stabilization of the blood glucose
levels in the normoglycemic state (<200 mg/dL) for up to 5 days
Stretch-Triggered Drug Delivery from Wearable Elastomer Films Containing Therapeutic Depots
Mechanical force-based stimulus provides a simple and easily accessible manner for spatiotemporally controlled drug delivery. Here we describe a wearable, tensile strain-triggered drug delivery device consisting of a stretchable elastomer and microgel depots containing drug loaded nanoparticles. By applying a tensile strain to the elastomer film, the release of drug from the microdepot is promoted due to the enlarged surface area for diffusion and Poisson’s ratio-induced compression on the microdepot. Correspondingly, both sustained drug release by daily body motions and pulsatile release by intentional administration can be conveniently achieved. Our work demonstrated that the tensile strain, applied to the stretchable device, facilitated release of therapeutics from microdepots for anticancer and antibacterial treatments. Moreover, polymeric microneedles were further integrated with the stretch-responsive device for transcutaneous delivery of insulin and regulation of blood glucose levels of chemically induced type 1 diabetic mice
Photo-Cross-Linked Scaffold with Kartogenin-Encapsulated Nanoparticles for Cartilage Regeneration
The regeneration of cartilage, an
aneural and avascular tissue,
is often compromised by its lack of innate abilities to mount a sufficient
healing response. Kartogenin (KGN), a small molecular compound, can
induce bone marrow-derived mesenchymal stem cells (BMSCs) into chondrocytes.
The previous <i>in vitro</i> study showed that kartogenin
also had a chondrogenesis effect on synovium derived mesenchymal stem
cells (SMSCs). Herein, we present the effect of an ultraviolet-reactive,
rapidly cross-linkable scaffold integrated with kartogenin-loaded
nanoparticles using an innovational one-step technology. <i>In
vivo</i> studies showed its potential role for cell homing, especially
for recruiting the host’s endogenous cells, including BMSCs
and SMSCs, without cell transplantation. Of note, the regenerated
tissues were close to the natural hyaline cartilage based on the histological
tests, specific markers analysis, and biomechanical tests. This innovative
KGN release system makes the chondrogenesis efficient and persistent