Preliminary Investigation on the Development of Diltiazem Resin Complex Loaded Carboxymethyl Xanthan Beads

Abstract

Abstract. The objective of this study was to develop a multiunit sustained release dosage form of diltiazem using a natural polymer from a completely aqueous environment. Diltiazem was complexed with resin and the resinate-loaded carboxymethyl xanthan (RCMX) beads were prepared by interacting sodium carboxymethyl xanthan (SCMX), a derivatized xanthan gum, with Al +3 ions. The beads were evaluated for drug entrapment efficiency (DEE) and release characteristics in enzyme free simulated gastric fluid (SGF, HCl solution, pH 1.2) and simulated intestinal fluid (SIF, USP phosphate buffer solution, pH 6.8). Increase in gelation time from 5 to 20 min and AlCl 3 concentration from 1 to 3% decreased the DEE respectively from 95 to 79% and 88.5 to 84.6%. However, increase in gum concentration from 1.5 to 2.5% increased the DEE from 86.5 to 90.7%. The variation in DEE was related to displacement of drug from the resinate by the gel forming Al +3 ions. While 75-82% drug was released in 2 h in SGF from various beads, 75 to 98% drug was released in 5 hour in SIF indicating the dependence of drug release on pH of dissolution media. Although the beads maintained their initial integrity throughout the dissolution process in both media, as evident from scanning electron microscopic studies, the faster release in SGF was accounted for higher swelling of the beads in SGF than in SIF. When release data (up to 60%) was fitted in power law expression, the drug release was found to be controlled by diffusion with simultaneous relaxation phenomena.

Novel interpenetrating network microspheres of xanthan gum–poly(vinyl alcohol) for the delivery of diclofenac sodium to the intestine—in vitro and in vivo evaluation

“…Although sodium carboxy methyl xanthan gum was used to prepare microparticles (Ray et al, 2008), in the literature of pharmaceutics we are not aware of preparation of microspheres from IPN of XG, which can be safely used in food and cosmetics without any specific quantity limitations (Katzbauer, 1998) and PVA for the controlled release of DS. Our aim was to study the potentiality of XG to form IPN network and highly safe XG may be more effective for the delivery of drugs by forming a novel IPN network of XG and PVA.…”

Polyethyleneimine-treated xanthan beads for prolonged release of diltiazem: in vitro and in vivo evaluation

“…One of the major disadvantages of inotropic gelation method is the low entrapment of water soluble drugs due to its rapid partitioning from the microparticles into the aqueous gelation medium during preparation. It has, however, been reported that if diltiazem, a water soluble drug, is embedded in carboxymethyl xanthan (CMX) microparticles in the form of drug-resin complex rather than as free drug, the drug entrapment efficiency of CMX microparticles may be as high as 95% (Ray, 2008). In spite of high drug loading, around 80% of diltiazem was found to be released in just two hours in acidic medium of pH 1.2 (Ray, 2008).…”

“…It has, however, been reported that if diltiazem, a water soluble drug, is embedded in carboxymethyl xanthan (CMX) microparticles in the form of drug-resin complex rather than as free drug, the drug entrapment efficiency of CMX microparticles may be as high as 95% (Ray, 2008). In spite of high drug loading, around 80% of diltiazem was found to be released in just two hours in acidic medium of pH 1.2 (Ray, 2008). Several polymers like chitosan, pectin, methyl cellulose have been used with sodium alginate to modify DEE and release rates of drug from alginate beads (Pillay and Fassihi, 1999;El Kamel, 2003).…”

Tailoring of locust bean gum and development of hydrogel beads for controlled oral delivery of glipizide

“…It was reported that barium chloride crosslinked carboxymethyl guar gum beads had a maximum bovine serum albumin (BSA) loading efficiency of 53% depending upon the concentration of barium (Ba+2) ions and released only 5% of the encapsulated BSA in pH 1.2 NaCl-HCl buffer in 6 h; however, the beads released almost 81% of its content within 4 h in pH 7.4 TRIS-HCl buffer (Thimma & Tammishetti, 2001). Recently, it has been reported that diltiazem-resin complex-loaded carboxymethyl xanthan beads released ∼ 75-82% drug in simulated gastric fluid within 2 h and 75-98% drug in simulated intestinal fluid within 5 h (Ray et al, 2008). It appears that each and every polymeric bead system has its merits and demerits; and none of these is a suitable carrier system for oral controlled drug delivery.…”