Biodegradable Elastomers Enabling Thermoprocessing Below 100 °C.

Biodegradable and biocompatible elastomers are highly desirable for many biomedical applications. Here, we report synthesis and characterization of poly(ε-caprolactone)--poly(β-methyl-δ-valerolactone)--poly(ε-caprolactone) (PCL-PβMδVL-PCL) elastomers. These materials have strain to failure values greater than 1000%.

Implantable and Degradable Thermoplastic Elastomer.

Biodegradable and implantable materials having elastomeric properties are highly desirable for many biomedical applications. Here, we report that poly(lactide)--poly(β-methyl-δ-valerolactone)--poly(lactide) (PLA-PβMδVL-PLA), a thermoplastic triblock poly(α-ester), has combined favorable properties of elasticity, biodegradability, and biocompatibility. This material exhibits excellent elastomeric properties in both dry and aqueous environments.

Cellulose nanocrystal effect on crystallization kinetics and biological properties of electrospun polycaprolactone.

Mechanical properties of tissue engineering nanofibrous scaffolds are of importance because they not only determine their ease of application, but also influence the environment for cell growth and proliferation. Cellulose nanocrystals (CNCs) are natural renewable nanoparticles that have been widely used for manipulating nanofibers' mechanical properties. In this article, cellulose nanoparticles were incorporated into poly(caprolactone) (PCL) solution, and composite nanofibers were produced.

Functional skeletal muscle constructs from transdifferentiated human fibroblasts.

Transdifferentiation of human non-muscle cells directly into myogenic cells by forced expression of MyoD represents one route to obtain highly desirable human myogenic cells. However, functional properties of the tissue constructs derived from these transdifferentiated cells have been rarely studied. Here, we report that three-dimensional (3D) tissue constructs engineered with iMyoD-hTERT-NHDFs, normal human dermal fibroblasts transduced with genes encoding human telomerase reverse transcriptase and doxycycline-inducible MyoD, generate detectable contractile forces in response to electrical stimuli upon MyoD expression.

Efficient release of immunocaptured cells using coiled-coils in a microfluidic device.

Label-free and affinity-based cell separation allows highly specific cell capture through simple procedures, but it remains a major challenge to efficiently release the captured cells without changing their structure, phenotype, and function. We report a microfluidic platform for label-free immunocapture of target cells and efficient release of the cells with minimal biochemical and biophysical perturbations. The method capitalizes on self-assembly of a pair of heterodimerizing coiled-coils, A and B.

Colloidal stability versus self-assembly of nanoparticles controlled by coiled-coil protein interactions.

Orientational discrimination of biomolecular recognition is exploited here as a molecular engineering tool to regulate nanoparticle self-assembly or stability. Nanoparticles are conjugated with the heterodimerizing coiled-coils, A and B, which associate in parallel orientation. Simply flipping the orientation of one coiled-coil results in either self-assembling or colloidally stable nanoparticles.