ABSTRACT
A gastro retentive floating drug delivery system with multiple-unit minitablets based on gas formation technique was developed for furosemide. The system consists of core units (solid dispersion of furosemide:povidone and other excipients), prepared by direct compression process, which are coated with two successive layers, one of which is an effervescent (sodium bicarbonate) layer and other one an outer polymeric layer of polymethacrylates. The formulations were evaluated for pharmacopoeial quality control tests and all the physical parameters evaluated were within the acceptable limits. Only the system using Eudragit RL30D and combination of them as polymeric layer could float within acceptable time. The time to float decreased as amount of the effervescent agent increased and, when the coating level of polymeric layer decreased. The drug release was controlled and linear with the square root of time. By increasing coating level of polymeric layer decreased the drug release. The rapid floating and the controlled release properties were achieved in this present study. The stability samples showed no significant change in dissolution profiles (f(2) = 81). The in vivo gastric residence time was examined by radiograms and it was observed that the units remained in the stomach for about 6 h.
Subject(s)
Diuretics/administration & dosage , Diuretics/pharmacokinetics , Drug Delivery Systems/methods , Furosemide/administration & dosage , Furosemide/pharmacokinetics , Tablets, Enteric-Coated/chemistry , Adult , Diuretics/chemistry , Drug Compounding , Furosemide/chemistry , Gastric Mucosa/metabolism , Humans , Male , Polymethacrylic Acids/chemistry , Radiography , Sodium Bicarbonate/chemistry , Solubility , Stomach/diagnostic imaging , Tablets, Enteric-Coated/administration & dosage , Tablets, Enteric-Coated/pharmacokinetics , Time Factors , X-Ray DiffractionABSTRACT
A gastro retentive floating drug delivery system with multiple-unit minitab's based on gas formation technique was developed in order to prolong the gastric residence time and to increase the overall bioavailability of the drug. The system consists of the drug-containing core units prepared by direct compression process, which are coated with three successive layers of an inner seal coat, effervescent layer (sodium bicarbonate) and an outer gas-entrapped polymeric membrane of an polymethacrylates (Eudragit RL30D, RS30D, and combinations of them). Only the system using Eudragit RL30D and combination of them as a gas-entrapped polymeric membrane could float. The time to float decreased as amount of the effervescent agent increased and coating level of gas-entrapped polymeric membrane decreased. The optimum system floated completely within 3 min and maintained the buoyancy over a period of 12 h. The drug release was controlled and linear with the square root of time. Increasing coating level of gas-entrapped polymeric membrane decreased the drug release. Both the rapid floating and the controlled release properties were achieved in the multiple-unit floating drug delivery system developed in this present study. The analysis of the parameter dissolution data after storage at 40 degrees C and 75% RH for 3 months showed, no significant change indicating the two dissolution profiles were considered to be similar (f2 value is more than 50).
