Biodegradable Defined Shaped Printed Polymer Microcapsules for Drug Delivery.

This work describes the preparation and characterization of printed biodegradable polymer (polylactic acid) capsules made in two different shapes: pyramid and rectangular capsules about 1 and 11 µm in size. Obtained core-shell capsules are described in terms of their morphology, loading efficiency, cargo release profile, cell cytotoxicity, and cell uptake. Both types of capsules showed monodisperse size and shape distribution and were found to provide sufficient stability to encapsulate small water-soluble molecules and to retain them for several days and ability for intracellular delivery. Capsules of 1 µm size can be internalized by HeLa cells without causing any toxicity effect. Printed capsules show unique characteristics compared with other drug delivery systems such as a wide range of possible cargoes, triggered release mechanism, and highly controllable shape and size.

Modification of PCL Scaffolds by Reactive Magnetron Sputtering: A Possibility for Modulating Macrophage Responses.

Direct current (DC) reactive magnetron sputtering is as an efficient method for enhancing the biocompatibility of poly(ε-caprolactone) (PCL) scaffolds. However, the PCL chemical bonding state, the composition of the deposited coating, and their interaction with immune cells remain unknown. Herein, we demonstrated that the DC reactive magnetron sputtering of the titanium target in a nitrogen atmosphere leads to the formation of nitrogen-containing moieties and the titanium dioxide coating on the scaffold surface. We have provided the possible mechanism of PCL fragmentation and coating formation supported by XPS results and DFT calculations. Our preliminary biological studies suggest that DC reactive magnetron sputtering of the titanium target could be an effective tool to control macrophage functional responses toward PCL scaffolds as it allows to inhibit respiratory burst while retaining cell viability and scavenging activity.