We have successfully prepared a bead-type adsorbent from two materials with different adsorption characteristics. Heavy metals were removed by greatly swollen egg shell membrane-conjugated chitosan beads. The egg shell membrane accumulated and removed precious metal ions from a dilute aqueous solution with a high affinity in a short contact time. Experiments suggested that chitosan beads could take up gold ions with great capacity and selectivity by conjugation with egg shell membrane. Under certain conditions, the selective removal of gold and copper in a mixture of gold and copper ions by egg shell membraneconjugated chitosan beads was 100% and 2%, respectively. Egg shell membrane-conjugated chitosan beads can be seen as a promising material to recover gold in wastewater from various industries, such as electroplating.Key words Chitosan beads · Egg shell membrane · Heavy and precious metal · Selective recovery for metal
Although bioassays are considered to be a rational method for environmental management, the procedure is generally too complicated to be applied to daily water quality management. In this study, the feasibility of using for application of a conventional QSAR (Quantitative Structure-Activity Relationship) method was examined to estimate the cytotoxicity of various pollutants found in environmental water. logP, pKa, and molecular weight were chosen as the physico/chemical properties of the pollutants, and defined equations for estimating cytotoxicity based on multiple linear regression analysis between these properties and in vitro cytotoxicity data from our previous results. As a result, a method for estimating cytotoxicity of environmental pollutants that had a certain probability (R>0.8) for the 255 chemicals was successfully developed. Considerably high reliability was shown in the leave-one-out prediction of multi-regression analysis. In addition, the cytotoxicity of environmental water samples was estimated based on multi-regression analysis, using as our samples leachates from 25 landfill sites in Japan. The method developed in this study estimated quantitatively the cytotoxicity of the environmental water from chemical analysis data without conducting a cytotoxicity test.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.