Rifabutin-loaded
Floating Gellan Gum Beads: Effect of Calcium and Polymer
Concentration on Incorporation Efficiency and Drug
Release
Anurag Verma1* and Jayant K Pandit2
1Department
of Pharmaceutics, College of Pharmacy, IFTM, Moradabad,
244001, 2Department of Pharmaceutics,
Institute of Technology, Banaras Hindu University,
Varanasi, India
*For correspondence:
E-mail:
anuragverma_kuntam@rediffmail.com or
anuragverma_iftm@yahoo.co.in Tel:
+91-9412581046, 5912360022; Fax: +91-5912360818
Received: 18 August
2010 Revised
accepted: 16 December 2010
Tropical
Journal of Pharmaceutical Research, February 2011;
10(1):
61-67
Abstract
Purpose:
To formulate rifabutin-loaded
floating gel beads for stomach-specific release.
Methods:
Rifabutin-loaded floating gellan gum beads were prepared
by ionotropic calcium-induced gelation in acidic medium.
In-vitro buoyancy and drug release studies were
performed using a USP dissolution apparatus type II in
0.01M HCl (ph 2.0) as the dissolution medium. The shape,
surface morphology and internal structure of the dried
beads were examined by scanning electron microscopy.
Fourier Transform infrared spectroscopy (FTIR) was
applied to investigate drug-polymer interactions.
Results:
The beads exhibited excellent buoyancy in simulated
gastric fluid (SGF) and remained buoyant for 18 h. Drug
incorporation efficiency of the beads ranged from 40 to
60 % and was dependent significantly (p < 0.05) on the
concentrations of calcium ions and gellan gum. Drug
release from the floating bead formulations was rapid,
with > 50 % of the drug released within 1 h. Increased
polymer concentration did not significantly (p < 0.05)
retard drug release.
Conclusion:
Incorporation efficiency
and release of rifabutin can be controlled by modulation
of the investigated parameters. The developed floating
gellan gum beads may be suitable for a potential oral
stomach-specific release system to treat stomach
infections such as multi-drug resistant Helicobacter
pylori infection.
Keywords:
Floating beads, Gellan gum, Incorporation efficiency,
Rifabutin, Stomach-specific release
