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The article introduces the concept of homophase adsorption of soluble Pb(II) from contaminated water using aqueous guar gum (GG). The process appears to be extremely handy since it avoids hectic sample preparation and adsorbent recovery stages. The results show that, addition of only 1000 ppm GG removes 56.72% of the contaminated Pb(II) within 150 min at 303 K. The best working pH has been found to be at 4.5. At this point GG molecules show greatest balance between negative zeta potential and high molecular size. Mechanistically, the adsorption follows Langmuir model since on formation of a monolayer, the positive Pb(II) prevent subsequent adsorption through strong electrostatic repulsion. The adsorption kinetics follows pseudo second order model. Both kinetics and thermodynamics of the process complies with the conventional hetero facial adsorption models despite huge procedural differences., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

This paper reports interesting differences between physical and mechanical properties of various membranes prepared from high and low molecular weight poly (vinyl alcohol) (PVA) and xanthan gum (XG) blends irradiated under low dose electron beam. The membranes were designed for sustained delivery of diltiazem hydrochloride through skin. Electron beam irradiation produced crosslinks and turned PVA into crystalline phase from its amorphous organization in the unirradiated state. PVA crystals were fibrillar at low XG content (1 wt.%) when the molecular weight was high while similar orientation at higher XG content (5 wt.%) when the molecular weight was low. Low molecular weight PVA-XG membranes showed equivalent physical properties under dry condition but wet-mechanical properties were superior for high molecular weight PVA-XG hybrids. Both of them showed slow and sustained diltiazem release but the later induced slightly slower release despite low drug encapsulation efficiency due to its better wet mechanical strength., (Copyright © 2013 Elsevier Ltd. All rights reserved.)