[en] Full text: Heavy metal poisoning remains a widespread problem in most industrial nations. People exposed to these heavy metal while come in contact heavy metal industries. Toxicity is more likely to result through inhalation or ingestion route. It affects a number of important body functions including central nervous and haematopoietic systems, besides hepatic and renal functions. Metal toxicity has also been reported to cause oxidative stress, leading to various physiological malfunctions. Rapid gastrointestinal transit could result in incomplete drug release from the drug delivery system above the absorption zone leading to diminished efficacy of the administered dose. In order to overcome above mentioned problem we have developed a floating drug delivery system of Calcium disodium edetate (CaNa₂EDTA) to provide prolong chelation therapy against various heavy metals. Floating matrix tablets of Ca Na₂EDTA were found to attain prolonged gastric residence time. A radiolabeling procedure of Ca-disodium-EDTA with ^99mTc was standardized using stannous chloride as reducing agent. The radiolabeled complex was added to the optimized tablet. Floating tablets were prepared by wet granulation technique, using polymers such as Hydroxy propyl methyl cellulose (HPMC, Methocel K100M CR), sodium alginate, Chitosan alone or in combination and other standard excipients. Sodium bicarbonate was incorporated as a gas-generating agent. The effects of sodium bicarbonate and poly vinyl alcohol on drug release profile and floating properties were investigated. Dissolution studies were performed to ensure that there was no leaching of radioactivity from the capsules. Gamma scintigraphy was performed in healthy human volunteers to assess the buoyancy of the optimized formulation. The optimized formulation remained buoyant during 4 hours of gamma scintigraphic studies in rabbits