A drug delivery system based on alginate microspheres: Mass-transport test and in vitro validation

Abstract

This paper presents a drug delivery system based on alginate microspheres. The biocompatibility, the flexibility in size and shape, the ability to entrap biomolecules as well as cells make alginate based systems ideal for in vivo drug delivery. Specifically, considering the target application of neural regeneration and the issue of neuroprotection for the development of innovative neuroprostheses, the authors describe a system for controlled release of Netrin-1, an axonal guidance protein. Microspheres dimensioning (based on specifications of drug release time and release modality), microspheres realization, and mass transport tests are described. The release efficiency is finally assessed by in vitro experiments of axonal guidance performed on embryonic neuronal cells. Preliminary results show that neuronal axons grow approaching the Netrin-1 source, thus indicating an efficient entrapment and release of the protein in the microspheres, in agreement with the microsphere modelling described before.

Effect of size on the cellular endocytosis and controlled release of mesoporous silica nanoparticles for intracellular delivery

“…Over the past few decades, controlled drug delivery technology has made substantial progress and became a hot topic in modern medication (Lesinski et al 2005;Ciofani et al 2007;Vallet-Regi et al 2007;Ciofani et al 2008). Up to now, according to the physicochemical properties of the drug encapsulated and the requirement of the clinic, various drug delivery platforms, including polymeric and inorganic matrix, have been designed and developed.…”

A hybrid approach for the control of axonal outgrowth: preliminary simulation results

“…Particular attention will be paid to the development of microspheres and to the study of the release kinetics. Preliminary in vitro tests, conducted with embryonic hippocampal neurons of rat (a commercialized immortalized primary line from Cambrex, R-Hi-501), microspheres of calcium alginate as source of chemical cues and Netrin-1 as attractive cue, are encouraging [4] and have shown the effectiveness of the release and the possibility to guide axons along defined trajectories (Fig. 5a, b), according to the direct modelling (Fig.…”

Alginate and chitosan particles as drug delivery system for cell therapy

“…Alginate particles were realized by a homogenization process and reticulation with calcium ions (Ciofani et al 2007). 5 ml of a 1% alginate (71240 from Fluka) solution was added drop by drop to 25 ml of an oil phase (iso-octane and Tween 85, a surfactant) and homogenized with a Ultra Turrax T18 basic (purchased from Ika) at 15,000 rpm for 2 min; cross-linking was then performed by the addition drop by drop of 5 ml of a 100% CaCl 2 aqueous solution and stirring for 2 min.…”