GREEN SYNTHESIS ZnO ANTIMICROBIAL NANOPARTICLE USING LEMONGRASS EXTRACT

• Main Author: Widhi Astuti, Selli
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/38493
• Institution: Institut Teknologi Bandung

In recent years, foodborne pathogen poisoning has become a worldwide health issue, which make the synthesis of antimicrobial food packaging is in a great demand. From this demand, new problem arises where the currently used antimicrobial are organic antimicrobial agents that have some drawbacks such as not being able to withstand high operating conditions and have short storage time. Metal nanoparticles or metal oxides can be the solution of this problem because both are resistant to high operating conditions, have longer storage times, and have stronger antimicrobial properties. To synthesize nanoparticles, an environmentally friendly reducing agent is required so that green synthesis becomes more attractive alternative than chemical synthesis. The objective of this study is to test the feasibility of the green synthesis route of ZnO antimicrobial nanoparticles with lemongrass plant extract. Lemongrass extracted using refluks for 15 minutes and then the extract mixed with Zn(NO3)2 to synthezised ZnO nanoparticle. There will be three reaction condition variation that being used. First is reaction temperature which will be varied at 60°C and ambient temperature, then reaction time will be varied at 6 hours and 24 hours, and last the precursor concentration will be varied at 0,1 M and 0,05 M. The synthesis result will be characterize using FTIR, XRD, DLS, TEM and being test in antimicrobial test using Escherichia coli bacteria. Based on the experiment, reaction condition that has the most impact in the synthesis result is precursor concentration. The best variation is synthesized at 6 hours, atmospheric temperature, and Zn(NO3)2] 0,1 M because ZnO is formed without calcination which being confirmed by XRD result. Variation that being synthesized at 24 hours, temperature 60°C and [Zn(NO3)2] 0,1 M needed calcination to form ZnO. However, this variation gives the smallest nanoparticle size (200 nm) based on the PSA result. TEM characterization results shows that the nanoparticle size that being characterized by PSA is the result of agglomeration, the real size of the particle for this variation is around 10 – 50 nm. This variation shows highest antimicrobial activity with 32% reduction at 50 mg/L concentration.