https://www.selleckchem.com/products/ABT-888.html The removal of hazardous heavy metals from the environment is imperative in order to have quality of water. Robust and eco-friendly technologies are required for the treatment of domestic, agricultural and industrial effluents. The effective treatment of wastewaters can be done using chemically modified polysaccharides as adsorbents of these toxic heavy metals. A popular method used by researchers to chemically polysaccharide adsorbents is carboxymethylation. Carboxymethyl polysaccharides, generally, have higher adsorption capacities for heavy metals than their unmodified forms. This paper reviews the applications of carboxymethyl polysaccharides as adsorbents of heavy metals in wastewaters. The review places particular emphasis on the use of carboxymethylated cellulose, chitosan and starch for the adsorption of heavy metals in contaminated aqueous environments. The literature reviewed generally showed that these carboxymethyl polysaccharides are good adsorbents of heavy metals. Some modifications, however, are required to enhance the chemical and mechanical strength of these carboxymethyl polysaccharides. Neutral TEMPO/NaClO/NaClO2 (TNN) oxidation, with NaClO2 as the primary oxidant under aqueous conditions at pH 6.8 was applied to selectively oxidize surface C6 primary hydroxyl groups of α-chitin to carboxylate groups. When 0.1 mmol TEMPO, 1 mmol NaClO and 20 mmol NaClO2 were added to 1 g α-chitin, the yield of water-insoluble oxidized chitin was 91.93 %, and the carboxylate content was 0.695 mmol/g. The TNN oxidized chitin (TNN-Ch) was mostly converted to individual nanofibrils by mechanical disintegration in water, with mostly widths of 20-24 nm and average lengths of 1 μm. Compared to chitin nanofibers produced by TEMPO/NaBr/NaClO system (TBN-ChNs), with average widths of 16.67 ± 7.9 nm and average lengths of 770 ± 170 nm, TNN-ChNs were wider, longer and had a higher aspect ratio; its films and hydrogels also sh