Controlled Release Of Biomolecules Research Articles

Stimuli-responsive polymer-complexed liposome nanocarrier provides controlled release of biomolecules

Smart nanocarriers have recently attracted attention for their effective delivery of biomolecules to the intestine without degradation in the oral delivery field. In this study, we prepared a stimulus-responsive polymer complex containing liposomal nanocarriers, termed capsosomes, and examined their multi-level release properties in the oral delivery of hydrophilic molecules. The capsosomes were constructed as a trilaurin-based solid lipid nanoparticle (SLN) assembly coated with chitosan (CSLNs), with liposomal subcompartments. We investigated the pH sensitivity and behavior of capsosomes in vitro under simulated gastrointestinal (GI) conditions. Positively charged CSLNs with negatively charged liposomal subcompartments were complexed by electrostatic forces, and their thermodynamic characteristics were examined using isothermal titration calorimetry. The optimized formulation was a 1.6 M ratio of liposomes to CSLNs, yielding physically stable capsosomes. The complexed liposomes were released from capsosomes at pH 7.0. We compared the structural integrity and retention times of free liposomes and capsosomes using an in vitro digestion model. The capsosomes showed improved stability and prolonged retention time under small intestinal conditions and bypassed the GI tract. Approximately 87% of the complexed liposomes were released and transferred to the small intestinal membrane. These results demonstrate the potential application of pH-sensitive capsosomes for the oral delivery of food nutraceuticals.

Graphene-based materials in drug delivery and growth factor release: A critical review

Abstract Graphene and its derivatives have attracted much attention in recent years due to their unique properties and functionalization ability in tissue engineering. In this work, effect of biomolecule adding in three groups of Graphene family (consisting of Graphene, Graphene Oxide and reduced Graphene Oxide), their composites and modified forms are studied. Although the Graphene family induces differentiation of stem cells, adding appropriate factors (such as growth factors, inducers and gene activator proteins) helps improve the adhesion, proliferation and differentiation of cells. The novelty of this work is to verifying the capability of specifically-induced differentiation and bioactive controlled release of biomolecules on Graphene-based substrates, Graphene filled substrates or Graphene coated substrates and explaining the important role of biomolecules in stem cells fate. The study indicates that Graphene family can release biomolecules (including growth factors and proteins) in a controlled manner and these additives significantly enhance or accelerate the adhesion, proliferation and differentiation of stem cells and induce the differentiation of stem cells to specific cells.

Enzyme-responsive polymer hydrogels for therapeutic delivery.

Enzymes play a central role in a spectrum of fundamental physiological processes and their altered expression level has been associated with many diseases and pathological disorders. Enzymes therefore can be exploited as a pristine biological trigger to tune material responses and to achieve controlled release of biomolecules at desired sites. This mini-review highlights enzyme-responsive polymer hydrogels for therapeutic delivery applications developed within the last five years, focusing on protease- and glycosidase-based catalyzed reactions. Strategies employed to produce responsive materials are described. Successful applications for controlled drug delivery are highlighted, and finally, future opportunities and challenges are presented.