Corban Swain

Three-dimensional metastructures with nanoscale feature sizes exhibit unique properties compared with structures with larger feature sizes, but are difficult to fabricate. Here we introduce implosion carving (ImpCarv), a method for photopatterning vacancies of complex geometry throughout materials, followed by isotropic shrinkage (>10-fold). ImpCarv works by photoactivating sensitizers to generate reactive oxygen species that cleave a swollen hydrogel at defined points, followed by controlled shrinkage via dehydration. ImpCarv creates three-dimensional metastructures where the refractive index of each point throughout a material can be specified with nanoscale precision via material presence or absence. By leveraging refractive index programmability for precise phase control, we demonstrate an all-optical machine learning device with nanoscale neuron sizes operating at visible wavelengths. ImpCarv may thus support diverse applications in nanophotonics and nanotechnology.

Hydrolytically degrading nano‐polyplexes (HDG‐NPs) that reverse charge through conversion of tertiary amines to carboxylic acids were investigated to improve intracellular un‐packaging of siRNA and target gene silencing compared to a non‐degradable analog (non‐HDG‐NPs). Both NP types comprised reversible addition‐fragmentation chain‐transfer (RAFT) synthesized diblock copolymers of a poly(ethylene glycol) (PEG) corona‐forming block and a cationic block for nucleic acid packaging that incorporated butyl methacrylate (BMA) and either dimethylaminoethyl methacrylate (DMAEMA, non‐HDG‐NPs) or dimethylaminoethyl acrylate (DMAEA, HDG‐NPs). HDG‐NPs decreased significantly in size and released significantly more siRNA (∼40%) than non‐HDG‐NPs after 24 h in aqueous solution. While both HDG‐NPs and non‐HDG‐NPs had comparable uptake and cytotoxicity up to 150 nM siRNA doses, HDG‐NPs achieved significantly higher target gene silencing of the model gene luciferase in vitro. High resolution FRET confocal microscopy was used to monitor the intracellular un‐packaging of siRNA. Non‐HDG‐NPs had significantly higher FRET efficiency than HDG‐NPs, indicating that siRNA delivered from HDG‐NPs was more fully un‐packaged and therefore had improved intracellular bioavailability. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 917–927, 2016.

Aims: The activity of the transcription factor c-Myc is dependent upon heterodimerization with Max to control target gene transcription. Small-molecule inhibitors of c-Myc–Max have exhibited low potency and poor water solubility and are therefore unsuitable for in vivo application. We hypothesized that a nanomedicine approach incorporating a cryptic c-Myc inhibitor prodrug could be delivered and enzymatically released in order to effectively inhibit melanoma. Materials & methods: An Sn-2 lipase-labile Myc inhibitor prodrug was synthesized and included in two αvβ3-targeted nanoparticle platforms (20 and 200 nm). The inherent antiproliferate potency was compared with the lipid-free compound using human and mouse melanoma cell lines. Results & conclusion: These data demonstrate for the first time a successful nanodelivery of c-Myc inhibitors and their potential use to prevent melanoma.

A superior and commercially exploitable 'green synthesis' of optically active carbon nanoparticle (OCN) is revealed in this work. The naked carbon particles (in vitro. Preliminary in vivo experiment showed high contrast enhancement in auxiliary lymphnode in a mouse model. The exceptionally rapid lymphatic transport of these particles suggests that such an approach may offer greater convenience and reduced procedural expense, as well as improved surgical advantage as the patient is positioned on the table for easier resection.