The existence of lead (Pb) compounds in waters can be caused of waste pollution from industrial activities such as dye and battery industries. Lead is toxic and able to cause some deseases. The aim of this study is to create solid phase from natural material as an alternative method for determination of lead in water samples. The solid phase is silica prepared from rice husks ash (RHA), was prepared and modified using chitosan. To achieve that aim, the optimization of silica : chitosan composition was performed. The influence of Pb 2+ concentration and citric acid concentration was studied to obtain optimum recovery of Pb 2+ . Interaction between Pb 2+ ion and solid phase silica -chitosan could be estimated based on the result. This showed the optimum composition of silica : chitosan was 65% silica : 35% chitosan with Cation Exchange Capacity (CEC) 0.00455 mek/g. Mass adsorbed Pb 2+ for 1 g silica : chitosan 65% was 9.715 mg/g. Optimum recovery of Pb 2+ on solid phase extraction was reached at concentration of Pb 2+ 10 ppm and citric acid concentration 0.05 M (88.25 % and 81.18 %). This result indicated that solid phase extraction prepared from silica -chitosan can be applied as an alternative method for Pb 2+ determination in water.
Molecularly Imprinted Polymers (MIPs) have specific recognition capabilities and have been widely used for electrochemical sensors with high selectivity. In this study, an electrochemical sensor was developed for the determination of p-aminophenol (p-AP) by modifying the screen-printed carbon electrode (SPCE) with chitosan-based MIP. The MIP was made from p-AP as a template, chitosan (CH) as a base polymer, and glutaraldehyde and sodium tripolyphosphate as the crosslinkers. MIP characterization was conducted based on membrane surface morphology, FT-IR spectrum, and electrochemical properties of the modified SPCE. The results showed that the MIP was able to selectively accumulate analytes on the electrode surface, in which MIP with glutaraldehyde as a crosslinker was able to increase the signal. Under optimum conditions, the anodic peak current from the sensor increased linearly in the range of 0.5–35 µM p-AP concentration, with sensitivity of (3.6 ± 0.1) µA/µM, detection limit (S/N = 3) of (2.1 ± 0.1) µM, and quantification limit of (7.5 ± 0.1) µM. In addition, the developed sensor exhibited high selectivity with an accuracy of (94.11 ± 0.01)%.
Secondary metabolites are one of the active substances in natural materials that are known to contain high antioxidants and are very beneficial for health. In addition to mangosteen, there are also natural ingredients that actually have high antioxidant content, but many people do not know about it, one of which is soursop fruit. In addition to the fruit, the skin of soursop fruit may contain antioxidants that are quite high. The purpose of this study was to determine the effect of different maceration times and powder sizes on the antioxidant activity of secondary metabolite compounds produced from ethanol-aquades extract of soursop fruit peel (Annona muricata L.). This study was conducted quantitatively with a descriptive research design where researchers conducted laboratory research conducted in triplo. This research used particle size variation of 50 mesh, 100 mesh, and 200 mesh and maceration time variation of 24 hours, 30 hours, 36 hours. From this study it can be seen that the difference in powder size and maceration time affects the results of antioxidant activity obtained. The optimum particle variation is using 200 mesh size, which is obtained antioxidant activity of 95.2%. While the optimum maceration time is for 24 hours, the yield is 94%. From this study it can also be seen that the ethanol-aquades extract of soursop fruit peel contains secondary metabolite compounds of triterpenoids, saponins, polyphenols and tannins.
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.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.