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Kaempferia galanga L. extract contains ethyl p-methoxycinnamate (EPMC) and ethyl cinnamate (EC), which have several pharmacological activities. EPMC and EC have been successfully isolated, but the %yield was low. Therefore, developing an isolation method to increase the %yield result of EPMC and EC is essential. The molecularly imprinted polymers have been applied to separate lot of active compounds from natural products with excellent results. MIP synthesis is usually performed using a single template with high selectivity for the target analyte but only detect single chemical compounds. Hence, this study synthesized multi-template molecularly imprinted polymers (MT-MIPs) for isolating EPMC and EC simultaneously using methacrylic acid as a functional monomer and ethylene glycol dimethacrylate or trimethyl propane trimethacrylate (TRIM) as a crosslinker. The study results indicate that MT-MIP produced with TRIM is more effective in separating EPMC and EC simultaneously in K. galanga L. extracts. However, the yields of EPMC and EC were still low. The yields of EPMC and EC in n-hexane extracts were 1.557 and 1.929%, with purity of 66.330 and 61.510%, respectively. Further research is necessary to determine the ideal functional monomer and its ratio to template molecules to obtain the excellent selectivity of the MT-MIPs used for simultaneously isolating EPMC and EC.

Background: Pigment Red 53 is a dangerous synthetic dye that is often added to cosmetics, even though its use in cosmetic products has been prohibited because of possible impacts on health. Faster and more sensitive detection of Pigment Red 53 is needed for onsite analysis to protect the community from illegal cosmetics that contain the dye. Indicator color charts are a kind of analytical method that can be used to detect Pigment Red 53 in cosmetic products, including lipstick, rouge, and eyeshadow. Such charts are practical, fast, and can be used for onsite analysis. Methods: In this study, an indicator for Pigment Red 53 detection was obtained through a reagent reaction that caused a specific color change. An indicator color chart was then produced by setting out in paper form the series of colors which resulted from the reaction of specific chemical reagents and Pigment Red 53 solutions at concentrations of 10, 20, 40, 60, 80, and 100 ppm. Results: The testing results showed that the indicator color chart may be used as an initial screening method for the detection of Pigment Red 53 in cosmetic products with a detectable minimum concentration of 10 ppm. Out of nine samples, only one (Eyeshadow 3) tested positive for Pigment Red 53. Further analysis was carried out on the indicator color chart and the results showed good agreement with TLC and UV–Vis spectrophotometry methods. Conclusion: The results reported in this paper demonstrate that the indicator color chart is a good prospective method for onsite analysis to detect Pigment Red 53 in cosmetic samples, with a lower detection limit compared to polymer‐based indicators. [ABSTRACT FROM AUTHOR]

Hg2+ is one of the most dangerous pollutants that can cause damage to organs and the immune system. The common detection methods of Hg2+ require sophisticated instrumentation and a long time for analysis. The purpose of this study was to develop a sensor for the detection of Hg2+ using filter paper immobilized by gold nanoparticles (AuNPs) conjugated with cyanuric acid (CA). The clear color change from pink to bluish purple is the response of the CA-AuNPs filter paper sensor to exposure to Hg2+. Detection can be observed visually with the naked eye and/or with imageJ software; the detection limit is 0.05 µM. The colorimetric response of the sensor was also selective towards Hg2+ after testing with different metal ions. In addition, the response from the sensor was also consistent for lake water samples spiked with Hg2+. The results of this research provide a promising basic technology for the development of sensors that are affordable, fast, portable, and easy to use for the detection and monitoring of Hg2+ levels in water. [ABSTRACT FROM AUTHOR]