Production and Characterization of Anisotropic Particles from Biodegradable Materials

Abstract

In recent years, production and characterization of anisotropic particles has become of interest in a wide range of scientific fields including polymer chemistry, drug delivery, electronics, energy, and nanotechnology. In this work, we demonstrate a novel formulation for production of anisotropic particles via an internal phase separation of biodegradable components. Specifically, binary mixtures of biodegradable polymers poly(lactic-co-glycolic acid), polycaprolactone, and biodegradable lipid Precirol (glyceryl palmitostearate) were dissolved in dichloromethane, emulsified, and prepared into anisotropic particles using a modified solvent evaporation technique. During the slow evaporation process the components self-assembled into anisotropic particles with distinct morphologies. Polymer/polymer formulations resulted in compartmentalized anisotropic heterodimer particles, while polymer/lipid combinations yielded "ice cream cone" shaped particles. It was found that addition of certain active pharmaceuticals resulted in an altered, pox-like segregation at the particle surface of polymer/polymer formulations. The anisotropic nature of the particles was subsequently characterized using optical microscopy, scanning electron microscopy, zeta potential, electrophoresis, and X-ray diffraction. Successful formulations presented here may potentially be employed as multicompartmental drug carriers with staggered drug release rates or alternatively as a colloidal excipient for an arsenal of pharmaceutical applications.

Biodegradable Janus Nanoparticles for Local Pulmonary Delivery of Hydrophilic and Hydrophobic Molecules to the Lungs

“…These particles exhibited enormous potential as a drug delivery system due to their dual functionality and anisotropic nature. 24,25 The beauty of these particles is that they can encapsulate in one complex system both hydrophobic and hydrophilic biologically active molecules. The encapsulation of dissimilar drugs into a two compartmental single particle allows for simultaneous delivery and release at the target site, thus avoiding problems with pharmacokinetics.…”

Synthesis of polymeric janus nanoparticles and their application in surfactant-free emulsion polymerizations

“…Synthesis of amphiphilic macro-RAFT diblock: RAFT-Sty 9 -bAAm 15 . Acrylamide and styrene were polymerized in the presence of PABTC, in a dioxane-water mixture, to yield an amphiphilic diblock copolymer (Scheme 1C).…”

“…We acknowledge the support of Dr Algi Serelis of DuluxGroup Australia for preparing the RAFT agent; Dr Meiliana Siauw for the synthesis of the RAFT-Sty 9 -b-AAm 15 …”

Recent Advances in the Emulsion Solvent Evaporation Technique for the Preparation of Nanoparticles and Nanocapsules

“…In this case, the morphology is kinetically but not thermodynamically stable. In addition, other factors such as the crystallization of polymers can also significantly influence the particle morphology [41,58]. Chen et al showed that the viscosity of the liquids played a significant role in the morphology of particles composed of polystyrene (PS) and poly(methyl methacrylate) (PMMA) [59].…”