Two-component cross-linkable gels for fabrication of solid oral dosage forms.

Current three-dimensional (3D) printing techniques involve the solidification of the injected materials by means of UV irradiation, evaporation of organic solvents, or harsh heating and cooling processes. These methods limit the printing of many sensitive bio-active molecules such as proteins. We describe a novel 3D printing technique based on two complementary liquid copolymers, PEG4-PCL-SC and PEG4-PCL-NH2, that are injected in a coordinated fashion and react with each other to form a pre-designed 3D pill. Printed pills swelled about 400% over 3 h, followed by moderate disintegration. Both prednisone and bovine serum albumin were incorporated into the printed pill, but while most of the prednisone was released depending on the ratio between the two complementary pre-polymers, only 40% of the bovine serum albumin was released from the pill. This unique 3D printing apparatus can be used to produce pills at home when the required medication does not handle current production techniques well and may have other possible biomedical applications. However, before this system can be considered for pharmaceutical applications, the low printing resolution, attributable to the slow gelation kinetics and the viscosity of the pre-polymers, should be addressed.

Near-Infrared Light Induced Phase Transition of Biodegradable Composites for On-Demand Healing and Drug Release.

Light responsive materials play an important role in many biomedical applications. Despite the great potential, commonly available systems are limited by their toxicity and lack of biodegradability. Here, an efficient light triggered system from safe, biodegradable star-poly(ethylene glycol) (star-PEG) and poly(ε-caprolactone) (PCL) with varying melting points controlled by the length of the CL segments is described. When incorporated with gold nanoshells (GNS) and exposed to near-infrared (NIR) irradiation, matrices temporarily disengage, thus allowing efficient on-demand healing and drug release. The responsiveness of this system to light, with its tailorable physical and healing properties, biocompatibility, biodegradability, and the capability to incorporate drugs and on-demand drug release are all desirable traits for numerous clinical applications.

A flexible polymersome system with tunable morphology and release profiles for efficient intracellular delivery.

Polymersomes are widely used as drug delivery system however they have shortcomings in drug-eluting properties that are attributable to the high molecular weight of the copolymers forming their membrane. Here we demonstrate for the first time how novel class of polymersomes from very short, liquid to soft star-shaped copolymers can be empowered to form an efficient drug delivery system. The copolymers undergo self-assembly in water into a stable, nano-sized rod or a spherical shape polymersomes. Increasing the Mw of the hydrophobic moieties the CMC value is decreased accompanied with the tendency to form a more spherical structure. The poorly water-soluble anticancer drug camptothecin was loaded into the fabricated polymersomes, resulting in a high drug loading content, and released over a period of over three days. Furthermore, this biocompatible system could deliver a variety of drugs intracellularly in a rapid yet controlled manner. Therefore, this nano system's tailorable properties, biocompatibility and ability to incorporate hydrophobic drugs and release them intracellularly are desirable traits for anti-cancer delivery system and other biomedical applications.