Syed Ishraque Ahmad, Nasreen Mazumdar
Department of Chemistry, Jamia Millia Islamia University, New Delhi 110025, India.
The technology for treatment of drinking water available in developed countries and urban areas is often inappropriate for villages and communities in developing regions. Therefore, regular interest is showing by scientific community in the development and testing of simple and inexpensive devices or systems of drinking water treatment which show promise for application in small communities or individual households in developing countries. In same way, the present work also focuses the development of slow iodine releasing polymeric matrices and tests its potential as drinking water purifier. The polymeric film was made from polyvinylalcohol crosslinked with malonic acid followed by iodination in iodine-ethanol solution (PMLA-I). A tablet formulation which consisted acetyl derivative of gum arabic followed by iodination in iodine-ethanol solution (AGA3-3.I2) and surrounded by a hydrophilic coating of ethyl cellulose (EC) and poly (ethylene glycol mixture). Both the PMLA-I film and AGA3-3.I2 coated tablet are biodegradable, non toxic and insoluble in water, slowly release disinfecting level of iodine in water. The PMLA-I film can be easily reused as polymer disinfectant followed by further iodination. Release of iodine from polymer matrices was determined by UV-VIS spectroscopy and volumetric titrations. The antimicrobial properties of PMLA-I film and AGA3-3.I2 coated tablets and their comparison with the reported antimicrobial activity of a commercially available water purifying tablet were studied against against E. coli (Gram negative) and S. aureus (Gram positive) bacteria by colony count method. Although PMLA-I film showed 99% reduction against an initial cell count of ~105 cfu/ml in 60 minutes, coated AGA3-3.I2 tablet showed same bactericidal activity in 24 hr. The developed water purifier would have advantages over commercially available water purifying tablet in terms of cost and residual iodine content in water. Read more…