Electronic Theses and Dissertation

Sintesis nanopartikel perak-kitosan spheres (agnp-kitosan spheres) telah selesai dilakukan dan karakterisasinya dilakukan dengan spektroskopi uv-vis, spektroskopi fourier transform infrared (ft-ir), x-ray diffraction (xrd), scanning electron microscopy (sem), dan nanozeta sizer. karakterisasi dengan spektroskopi uv-vis menunjukkan bahwa agnp-kitosan spheres memberikan serapan optimum pada panjang gelombang 410 nm. spektrum xrd menunjukkan bahwa struktur agnp-kitosan spheres berbentuk kristal dan bulat. karakterisasi menggunakan sem menunjukkan bahwa agnp-kitosan spheres dengan penambahan naoh 20% menghasilkan ukuran partikel terkecil yaitu 46,91 nm dan memiliki struktur yang halus dan relatif tidak berpori. analisis menggunakan nanozeta sizer menunjukkan bahwa nilai zeta potensial dan nilai polydispersity index (pdi) dari agnp-kitosan spheres cenderung meningkat dengan meningkatnya konsentrasi naoh. hasil pengujian aktivitas antimikroba menunjukkan agnp-kitosan spheres dengan konsentrasi naoh tertinggi menghasilkan diameter zona hambat tertinggi terhadap s.aureus, e.coli dan c.albicans, dengan diameter zona hambat masing-masing yaitu 19,5 mm, 18,56 mm dan 12,25 nm. kata kunci : nanopartikel perak, kitosan, aktivitas antimikroba

Synthesis of silver nanoparticles-chitosan spheres (AgNPs-chitosan spheres) has been completed and its characterization was fulfilled by UV–vis spectroscopy, Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and zetasizer nano. UV-vis spectroscopy characterization showed that AgNPs-chitosan spheres gave optimum absorption at a wavelength of 410 nm. The XRD spectra showed that the structure of AgNPs-chitosan spheres were crystalline and spherical. Characterization by SEM showed that AgNPs-chitosan spheres with the addition of 20% NaOH, resulted in the lowest average particle sizes of 46.91 nm and produced particles with smooth and relatively non-porous structures. The analysis using zetasizer nano showed that the zeta potential value and the polydispersity index (PdI) value of the AgNPs-chitosan spheres tended to increase with an increased NaOH concentration. The results of the microbial activity screening showed that the AgNPs-chitosan spheres with highest concentration of NaOH, produced the highest inhibition zone diameters against S.aureus, E.coli and C.albicans, with inhibition zone diameters of 19.5 mm, 18.56 mm and 12.25 mm, respectively. Keywords: silver nanoparticles, chitosan, antimicrobial activity