(208a) Inkjet Fabrication of Composite Particles with Solid Inclusions for Drug Delivery and Catalytic Reactions

Inkjet fabrication of composite particles with solid
inclusions for drug delivery and catalytic reactions

Dohnal J., ?tìpánek F.

Institute of
Chemical
Technology, Department of Chemical Engineering

Laboratory of
Chemical Robotics

Tel:
+420 220 443 046, email: dohnalj@vscht.cz

Calcium alginate
is very often used for the encapsulation of living cells or enzymes for bioapplications ^[1,2,3]. An active substance (living cells, enzymes
or catalyst particles) can be dispersed or dissolved in the starting sodium alginate
solution and subsequently encapsulated in the beads by calcium ions.

Alginate beads
can be prepared by different techniques from simple dropping of alginate
solution to a calcium pool to precipitation in a microfliudic
device. We use inkjet printing in this work. This technique can generate small microdroplets of a liquid with viscosity of up to 25 mPas with a diameter from 40 to 80 μm.
Stable dispersions are possible to printing and this work uses it for their
aims.

The aim of this
work is preparation of composite microparticles from
calcium alginate with inner inclusion for artificially started control release
of active substances or for fabrication of alginate beads with inner solid inclusions
or catalysts which can be used as microreactors for artificially
started reaction. 1% (w/w) of sodium alginate solutions with model particles
from TiO₂ or composite SiO₂/Fe₃O₄ particles
was used as inner inclusions. Release kinetics of model substances (from hollow
SiO₂/Fe₃O₄ particles) or catalytic properties
(inclusions from TiO2) was investigated.

Figure
 SEQ Figure \* ARABIC 1: Calcium alginate beads from dispersion of TiO₂ in
alginate solution with concentration 1,95 (A), 3,9 (B)
5,85 (C) and 7,8 (D) vol. % of inner solids.

1)      
Anal,
A. K.; Stevens, W. F. Chitosan-alginate multilayer
beads for controlled release of ampicillin. Int.
J. Pharm. 2005, 290, 45?54.

2)      
Murua, A.; et al. Cell microencapsilation
technology: Towards clinical application. J. Controlled Release 2008,
132, 76?83.

3)      
Morch, Ý. A; et al. Effect of Ca²⁺, Ba²⁺ and Sr²⁺
on Alginate Microbeads. Biomacromolecules
2006, 7, 1471?1480.