AKTIVITAS ANTIBAKTERI DAN KARAKTERISTIK MEMBRAN NANOKOMPOSIT KITOSAN/AMMONIUM KLORIDA/ PEG/ MWCNT - Ainnaya Annisa, - (2020)
ABSTRAK Penelitian ini bertujuan untuk memodifikasi membran nanokomposit kitosan/PEG/MWCNT dengan ammonium klorida (NH4Cl) sebagai agen antibakteri untuk mengatasi permasalahan biofouling pada membran. Sintesis membran nanokomposit dilakukan melalui metode solution mixing dan casting, dengan penambahan NH4Cl secara bervariasi (50-400 ppm), pada kondisi optimum yang diperoleh pada penelitian sebelumnya. Membran hasil sintesis diuji aktifitas antibakterinya menggunakan metode disc diffusion dan total plate counting terhadap bakteri gram positif S.aureus dan gram negative E.coli. Karakterisasi membran dilakukan menggunakan analisa spektroskopi FTIR, hidrofilisitas, porositas, kekuatan mekanik (stress) dan elongasi (%strain). Hasil penelitian menunjukkan bahwa penambahan NH4Cl meningkatkan aktifitas antibakteri (biofouling) pada membran kitosan/PEG/MWCNT dengan zona inhibisi 13 mm dan 7.3 mm pada minimum inhibitory concentration (MIC) terhadap S.aureus dan E.coli adalah 50 ppm dan 100 ppm, secara berturut-turut. Peningkatan aktivitas antibakteri membran kitosan/ PEG/MWCNT berbanding lurus dengan penambahan NH4Cl ditunjukkan dengan kenaikan total bacteria killing ratio (%BKR) untuk S.aureus (3.2% sampai 98.4%) dan E.coli (16% sampai 87%). Spekra FTIR menunjukkan interaksi antara NH4Cl dan membran nanokomposit Kitosan/PEG/MWCNT ditunjukan dengan kenaikan intensitas setiap penambahan konsentrasi NH4Cl. Penambahan NH4Cl memodifikasi hidrofilisitas membran (contact angle 92⁰ menjadi 83⁰), sifat mekanik membran (elastisitas 20% menjadi 22% dan strength 6.5 MPa menjadi 4.8 MPa), dan porositas membran (48.2% menjadi 52%). Kata kunci: membran nanokomposit, antibakteri, kitosan/PEG/MWCNT, ammonium klorid-a.  ABSTRACT This study aims to modify the chitosan / PEG / MWCNT nanocomposite membrane with ammonium chloride (NH4Cl) as an antibacterial agent to overcome biofouling problems in membranes. Nanocomposite membrane synthesis was carried out by methods solution mixing and casting, with the addition of NH4Cl varies (50-400 ppm), at the optimum conditions obtained in previous studies. The synthesized membrane was tested for its antibacterial activity using the method disc diffusion and total plate counting against gram-positive S.aureus and gram-negative E. coli. Membrane characterization was performed using FTIR spectroscopic analysis, hydrophilicity, porosity, mechanical strength (stress) and elongation (% strain). The results showed that the addition of NH4Cl increased the antibacterial activity (biofouling) on the chitosan / PEG / MWCNT membrane with 13 mm and 7.3 mm inhibition zones at the minimum inhibitory concentration (MIC) against S.aureus and E.coli, 50 ppm and 100 ppm. , respectively. The increase in the antibacterial activity of chitosan / PEG / MWCNT membranes was directly proportional to the addition of NH4Cl, indicated by an increase in the total bacteria killing ratio (% BKR) for S.aureus (3.2% to 98.4%) and E.coli (16% to 87%). FTIR spectra show the interaction between NH4Cl and the chitosan/PEG/MWCNT nanocomposite membrane indicated by an increase in the intensity of each addition of NH4Cl. The addition of NH4Cl modified membrane hydrophilicity (contact angle 92 (to 83⁰), membrane mechanical properties (elasticity 20% to 22% and strength 6.5 MPa to 4.8 MPa), and membrane porosity (48.2% to 52%). Keywords: nanocomposites filtration membrane, biofouling, antibacteria, chitosan, PEG, MWCNT, ammonium chloride.