Komposit kitosan-silika dan kitosan-glutaraldehid sebagai agen antibakteri pada kain katun

JUNAIDI, Ahmad Budi, Dr. Indriani Kartika, M.Si

2008 | Tesis | S2 Ilmu Kimia

Telah dilakukan kajian tentang pelapisan agen antibakteri kitosan pada kain katun menggunakan agen crosslinking silika dan glutaraldehid. Kitosan dibuat dari kitin kulit udang melalui proses deasetilasi bertahap. Penentuan derajat deasetilasi dan gugus fungsional kitosan menggunakan metode spektroskopi FTIR. Penentuan berat molekul kitosan menggunakan metode viskometri. Pelapisan kitosan, kitosan-silika dan kitosan-glutaraldehid pada kain katun menggunakan metode pad-dry-cure. Karakterisasi lapisan menggunakan analisis spektroskopi FTIR, UV-Vis reflektansi, difraktometri XRD dan analisis SEM. Kestabilan lapisan diuji melalui proses laundering menggunakan Tween-20. Aktivitas antibakteri kitosan dan kain yang dilapisi kitosan dilakukan terhadap bakteri S. aureus dengan metode shake flask. Pertumbuhan bakteri dimonitor berdasarkan optical density larutan bakteri. Hasil penelitian menunjukkan bahwa derajat deasetilasi kitosan semakin meningkat sejalan dengan semakin banyaknya tahapan proses deasetilasi yang dilakukan terhadap kitin. Proses deasetilasi yang berulang tidak mempengaruhi berat molekul kitosan yang dihasilkan. Aktivitas antibakteri kitosan semakin meningkat sejalan dengan meningkatnya derajat deasetilasi kitosan. Efek konsentrasi kitosan terhadap aktivitas antibakterinya semakin meningkat dengan urutan sebagai berikut : 0 ppm (asam asetat 100 ppm) < 500 ppm < 100 ppm < 50 ppm < 200 ppm. Hasil analisis menggunakan spektrofotometer FTIR, UV-Vis reflektansi dan difraktometer XRD menunjukkan bahwa interaksi kitosan dengan kain, silika dan glutaraldehid melibatkan gugus aktif –NH2. Penambahan silika dan glutaraldehid menurunkan efektivitas kitosan sebagai agen antibakteri, tetapi mampu meningkatkan kestabilan lapisan kitosan pada kain terhadap proses laundering.

Study of chitosan as antibacterial agent on cotton fabric using glutaraldehid and silica sol as crosslinking agent has been done. Chitosan was prepared by multistage alkali treatment of chitin from the shrimp’s shell. The FTIR spectroscopy was used to determine deacetylation degree and functional groups of chitosan. Viscometry was used to determine molecular weight of chitosan. Chitosan, chitosan-silica and chitosan-glutaraldehyde were deposited on cotton fabric by employing pad-dry-cure dip-coating technique. The coatings were characterized by infrared spectroscopy, X-ray difraction, UV-Vis reflectance spectroscopy and SEM analysis. The coating stability on cotton fabric over the washing process was tested by laundering the coated-fabrics using Tween-20 surfactant. Antibacterial activities of the coated-cotton fabrics toward Staphylococcus aureus were determined by shake flask method. The growths of S. aureus were monitored by examining the optical density of bacteria solution. The results showed that chitosan prepared by multistage alkali treatment had higher deacetylation degree than those of obtained by continuous alkali treatment. Multistage alkali treatment didn’t influence the chitosan’s molecular weight. Antibacterial activity of chitosan having high deacetylation degree was higher than that of low deacetylation degree chitosan samples. The effect of concentration of chitosan on its antibacterial activity is variable according to the following sequence : 0 ppm < 500 ppm < 100 ppm < 50 ppm < 200 ppm. The results of analysis using infrared spectrophotometer, UV-Vis reflectance, and X-ray Difractometer indicated that the interaction of chitosan with cotton fabric, silica and glutaraldehyde using -NH2 groups. Composites of silica-chitosan and glutaraldehyde-chitosan have shown reduced antibacterial activity. Though, the antibacterial durability were improved ignificantly over repeated laundering.

Kata Kunci : Kain antibakteri, kitosan-silika, kitosan-glutaraldehid, katun, Antibacterial fabric, chitosan-silica, chitosan-glutaraldehyde, cotton