ENKAPSULASI DAN STUDI PELEPASAN KURKUMIN DARI BEADS ALGINAT-KITOSAN DENGAN PENAMBAHAN ASAM LAURAT SEBAGAI EMULSIFIER

NIHAYATUN NIAMAH, Dr. Dwi Siswanta, M.Eng; Dr. Roto, M.Eng

2014 | Skripsi | KIMIA

Telah dilakukan studi pelepasan kurkumin dari beads alginat-kitosan dengan penambahan asam laurat sebagai emulsifier. Tujuan penelitian ini untuk mengetahui pengaruh konsentrasi asam laurat, konsentrasi kurkumin, komposisi etanol, dan pH pelarut terhadap laju reaksi dan mekanisme pelepasan kurkumin dari beads. Beads dibuat dengan cara melarutkan natrium alginat 3% (b/v) dalam akuades lalu ditambahkan asam laurat dan kurkumin dalam etanol 96%. Campuran diaduk selama kurang lebih 24 jam hingga homogen dan diinjeksikan ke dalam 20 mL larutan CaCl2 5% (b/v) kemudian direndam dalam larutan kitosan 0,25% (b/v) pH 5 selama 1 jam. Beads dikarakterisasi dengan spektrometer FTIR dan SEM. Laju pelepasan kurkumin dari beads diteliti secara in vitro selama 6 jam dalam buffer Tris-HCl. Konsentrasi kurkumin yang terlepas pada berbagai rentang waktu diukur menggunakan spektrofotometer UV-Vis. Kinetika pelepasan kurkumin dikaji menggunakan model orde nol, orde satu, Higuchi, dan Korsmeyer-Peppas. Spektra FTIR menunjukkan bahwa muncul serapan baru pada 1548 cm-1 (gugus NH3+) dikarenakan adanya interaksi alginat dengan kitosan, dan 2854 cm-1 (Csp3-H asam laurat) serta terjadi pergeseran bilangan gelombang pada puncak serapan gugus OH, gugus COOH dari alginat. Citra SEM menunjukkan terjadi erosi pada pH 1. Hampir semua mekanisme pelepasan kurkumin mengikuti model Korsmeyer-Peppas secara difusi dan erosi terkendali (anomalous transport). Penambahan asam laurat dan penurunan pH larutan menyebabkan perubahan mekanisme mengikuti model Higuchi. Kata kunci: asam laurat, beads, alginat, kitosan, kurkumin.

The release of curcumin from beads of alginate-chitosan by adding lauric acid as emulsifer had been studied. The purpose of this research is to understand the effect of lauric acid concentration, curcumin concentration, ethanol composition, and solvent pH on releasing rate and mechanism of curcumin from beads. The beads were prepared by dissolving sodium alginat 3% (w/v), then by adding lauric acid and curcumin in ethanol 96%. The solution was mixed for 24 hours until homogen and was injected to 20 mL solution of CaCl2 5% (w/v) and was soaked in chitosan solution 0,25% (w/v) for 1 hours. The beads were characterized using spectrometer FTIR and SEM. In vitro release rate of curcumin was investigated for 6 hours in Tris-HCl buffer. The concentration of curcumin released at various time intervals was measured by UV-Vis spectrophotometer. The curcumin release kinetics was analyzed by zero order model, first order, Higuchi, and Korsmeyer-Peppas. The FTIR spectra showed that there are new bands at 1548 cm-1 (NH3+ groups) caused by alginate-chitosan interaction, 2854 cm-1 (Csp3-H lauric acid) and shifting of wavelength number of OH groups and COOH groups of alginate's bands. The SEM images showed that erosion in pH 1 was occured. Curcumin release mechanism closely followed Korsmeyer-Peppas model controlled by diffusion and erosion. Addition of lauric acid and decrease in pH of solution caused mechanism alteration followed Higuchi model.

Kata Kunci : asam laurat, beads, alginat, kitosan, kurkumin/ lauric acid, beads, alginate, chitosan, curcumin