PROFILING THE BINDING AND RELEASE OF IMMOBILIZED INSULIN ON THE BIOSILICA OF CYCLOTELLA STRIATA FROM TANJUNG BIDADARI INDONESIA

• Main Author: Ayunita Azahra, Putri
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/87416
• Institution: Institut Teknologi Bandung

Cyclotella striata TBI, a marine diatom, possesses a porous silica shell. This porous biosilica has potential as a drug delivery matrix for medications, such as Indomethacin and Gentamicin. However, research on biosilica as a drug delivery system has primarily focused on simple organic compounds, leaving more complex drugs, like peptide insulin, unexplored. Insulin, a hormone regulating blood sugar levels, is typically administered subcutaneously to diabetic patients. This method can lead to adverse effects like hypoglycemia. Consequently, alternative delivery methods, such as oral administration, are being explored. A significant challenge in oral insulin delivery is developing a system that preserves insulin's bioavailability within the digestive tract. This study aimed to evaluate the adsorption and release capabilities of Cyclotella striata TBI biosilica for insulin in simulated intestinal fluid. The research steps include culturing Cyclotella striata TBI, isolating its biosilica, and investigating insulin binding using adsorption and incipient wetness impregnation methods. The release of insulin in simulated intestinal fluid was also studied. Biosilica was characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Fluorescence (XRF), and Scanning Electron Microscopy (SEM). The binding and release profiles of insulin were determined using UV Vis, Circular Dichroism (CD), and fluorescence spectroscopy. Results indicated a biomass productivity of 194.42 mg L?¹ day?¹ for Cyclotella striata and a biosilica productivity of 2.82 mg L?¹ day?¹. The XRF characterization result confirmed a 100% SiO? content in the biosilica based on XRF analysis. In addition, the FTIR spectrum demonstrated characteristic Si-O-Si peaks at 462, 808, and 1082 cm?¹. Insulin adsorption onto biosilica followed the Sips isotherm model with a maximum adsorption capacity of 0.103 mg insulin g?¹ SiO?. The release of insulin in simulated intestinal fluid adhered to a pseudo-second-order kinetic model. The desorbed insulin exhibited an emission peak at 562 nm, suggesting the formation of insulin fibrils. CD spectra further supported this showing an increased percentage of beta-sheet secondary structures in the desorbed insulin.