Green Synthesis of Silver Nanoparticles using Coffea Canephora Fruit Skin Extract and Its Application for Mercury Detection in Face Cream Samples
Hermin Sulistyarti, Muhammad Mashuri Utama, Ari Muchson Fadhila, Anggita Cahyaningrum, Revika Julia Murti, Ayu Febriyanti

Chemistry Department, Faculty of Mathematics and Natural Sciences, Brawijaya University, Jl. Veteran 1, Malang, 65145, Indonesia
LCAMIA: Research Centre for Low Cost and Automated Method & Instrumentation Analysis, Brawijaya University, Malang, 65145, Indonesia

Abstract

Mercury is one of the most toxic heavy metals causing harmful effects on the human body- meanwhile, mercury is found in some face cream products to give a whitening effect. The upper limit concentration of mercury in skin lightening product defined by the Food and Drug Administration (FDA) is under 1 ppm as Hg^{2+}. A new green analytical spectrophotometric method for mercury analysis has been developed by employing natural reagent from fruit skin extract of robusta coffee (Coffea canephora) as a bioreductor for silver ions as well as stabilizer for the AgNPs product. The detection principle of this method is based on based on the decrease of the colour intensity of silver nanoparticles (AgNPs) after the addition of Hg^{2+} ions due to the reoxidization of the AgNPs by Hg^{2+} ions to colorless Ag^{+} ions. To achieve the greatest sensitivity, linearity of measurement, and validity the method was optimized towards the volume of AgNPs and reaction time. In this research, the synthesized AgNPs were also characterized by UV-Vis Spectrometry as well as particle size analyzer (PSA) to determine the size of nanoparticles. The result showed that the optimum conditions were attained at 3 mL AgNPs solution and 3 min. reaction resulting a linear measurement of Hg^{2+} in the range of 0-15 mg/L with LOD and LOQ of 0.039 and 0.130 mg/L respectively. This method is quite selective and has been validated by applying to real face cream samples with satisfactory results supported by average recoveries of close 100 %.

Keywords: Mercury, Green Synthesis, Silver Nanoparticles, Coffee Fruit Skin, Spectrophotometry

Topic: Analytical Chemistry