Bioavailability Enhancement and Targeting of Stomach Tumors Using Gastro-Retentive Floating Drug Delivery System of Curcumin—“A Technical Note”

Abstract

Effective delivery of the drugs to the stomach, for local action and treatment of gastric disorders such as gastric cancer, gastric ulcers can be achieved by floating dosage forms like single and multiple unit gas generating systems, hollow microspheres, hydrodynamically balanced systems, swelling or expanding systems, mucoadhesive systems and other gastroretentive dosage forms (1). Curcumin is a major pigment of the Curcuma species, commonly used as a yellow coloring and flavoring agent in foods particularly in South Asia (2). Use of curcumin in traditional medicine and as a household remedy for various diseases, including biliary disorders, anorexia, cough, diabetic wounds, hepatic disorders; rheumatism and sinusitis (3) has been well documented. The novel trends in medicine have led to extensive investigations to establish the wide spectrum of biological and pharmacological actions of this phytochemical. Curcumin has been reported to possess anti-inflammatory, antioxidant, anticarcinogenic, antimutagenic, anticoagulant, antiarthritic, antibacterial, antifungal, antiprotozoal, antiviral, anti-Alzheimer, anti-psoriatic and neuroprotective activities (4). The efficacy, pharmacological safety, cost effectiveness of curcumin and no-dose limiting toxicity (4) has also prompted many researchers to further investigate this molecule. However, it has also been recognized that the therapeutic effectiveness of curcumin is limited due to its poor circulating bioavailability and absorption from the gastrointestinal tract. Numerous attempts have been made to improve the solubility of curcumin by complex formation or interaction with various macromolecules like gelatin, polysaccharides and cyclodextrins (5,6) preparation of solid dispersions with polyvinyl pyrrolidone (7) and prodrugs of curcumin (8). Present work was designed to improve the aqueous solubility of curcumin at acidic pH by incorporating it into β-cyclodextrin (β-CD) complex. Further to improve absorption of curcumin–β-CD complex from stomach, to target stomach tumors and to prevent degradation of curcumin in the alkaline environment of intestine, a floating drug delivery system (FDDS) with sustained release characteristics was developed.