Development and evaluation of gastroretentive norfloxacin floating tablets
Floating matrix tablets of norfloxacin were developed to prolong gastric residence time, leading to an increase in drug bioavailability. Tablets were prepared by the wet granulation technique, using polymers such as hydroxypropyl methylcellulose (HPMC K4M, HPMC K100M) and xanthan gum. Tablets were evaluated for their physical characteristics, viz., hardness, thickness, friability, and mass variation, drug content and floating properties. Further, tablets were studied for in vitro drug release characteristics for 9 hours. The tablets exhibited controlled and prolonged drug release profiles while floating over the dissolution medium. Non-Fickian diffusion was confirmed as the drug release mechanism from these tablets, indicating that water diffusion and polymer rearrangement played an essential role in drug release. The best formulation (F4) was selected based on in vitro characteristics and was used in vivo radiographic studies by incorporating BaSO4. These studies revealed that the tablets remained in the stomach for 180 ± 30 min in fasting human volunteers and indicated that gastric retention time was increased by the floating principle, which was considered desirable for the absorption window drugs.
S. Baumgartner, J. Kristl, F. Vrecer, P. Vodopivec and B. Zorko, Optimization of floating matrix tablets and evaluation of their gastric residence time, Int. J. Pharm. 195 (2000) 125--135; DOI: 10.1016/S0378-5173(99)00378-6.
B. N. Sing and K. H. Kim, Floating drug delivery systems: an approach to oral controlled drug delivery via gastric retention, J. Control. Rel. 63 (2000) 235--259; DOI: 10.1016/S0168-3659(99)00204-7.
A. Rubinstein and D. R. Friend, Specific Delivery to the Gastrointestinal Tract, in Polymeric Site-Specific Pharmacotherapy (Ed. A. J. Domb), Wiley, Chichester 1994, pp. 283--285.
W. A. Ritschel, Targeting in the gastrointestinal tract: new approaches, Methods Find, Exp. Clin. Pharmacol. 13 (1991) 313--316.
C. Mahesh, J. Paras, C. Sachin, S. Rajesh and V. Pradeep, Development of sustained release gastroretentive drug delivery system for ofloxacin: in vitro and in vivo evaluation, Int. J. Pharm. 304 (2005) 178--184; DOI: 10.1016/j.ijpharm.2005.08.009.
J. Varshosaz, N. Tavakoli and F. Roozbahani, Formulation and in vitro characterization of ciprofloxacin floating and bioadhesive extended-release tablets, Drug Del. 13 (2006) 277--285; DOI: 10.1080/10717540500395106.
K. M. Gerald, Norfloxacin, in AHFS Drug Information, The American Society of Health System Pharmacists, Bethesda 2004, pp. 396--402.
C. Mazuel, Norfloxacin, in Analytical Profiles of Drug Substances (Ed. K. Florey), Vol. 20, Academic Press, San Diego 1991, pp. 557--600.
Noroxin tablets, in Physician Desk Reference, 61st ed., Thomson PDR, Montvale 2007, pp. 2032--2038.
United States Pharmacopeia 28, National Formulary 23, USP Convention, Rockville 2005, pp. 2745.
T. Higuchi, Rate of release of medicaments from ointment bases containing drugs in suspensions, J. Pharm. Sci. 50 (1961) 874--875.
R. W. Korsmeyer, R. Gurny, E. Doelker, P. Buri and N. A. Peppas, Mechanisms of solute release from porous hydrophilic polymers, Int. J. Pharm. 15 (1983) 25--35; DOI: 10.1016/0378-5173(83)90064-9.
N. A. Peppas, Analysis of Fickian and non-Fickian drug release from polymers, Pharm. Acta Helv. 60 (1985) 110--111.
L. Whitehead, J. T. Fell, J. H. Collett, H. L. Sharma and A. M. Smith, Floating dosage forms: an in vivo study demonstrating prolonged gastric retention, J. Control. Rel. 55 (1998) 3--12; DOI: 10.1016/S0168-3659(97)00266-6.
C. S. L. Chiao and J. R. Robinson, Sustained-release Drug Delivery Systems, in Remington: The Science and Practice of Pharmacy (Ed. A. R. Gennaro), 19th ed., Vol. 2, Lippincott, Williams and Wilkins, Philadelphia 2000, pp. 1660--1675.
J. W. Moore and H. H. Flanner, Mathematical comparison of curves with an emphasis on in vitro dissolution profiles, Pharm. Technol. 20 (1996) 64--74.
Guidance for Industry (Dissolution Testing of Immediate Release Solid Oral Dosage Forms), US Department of Health and Human Services, Food and Drug Administration, Center for Drug Evaluation Research (CDER), Aug 1997, pp. 9; www.fda.gov/cder/guidance.htm; access date April 22, 2009.
K. Mitchell, J. L. Ford and D. J. Armstrong, The influence of concentration on the release of drugs from gels and matrices containing Methocel, Int. J. Pharm. 100 (1993) 155--163; DOI: 10.1016/0378-5173(93)90086-U.