MODIFIKASI BIOSENSOR LOCALIZED SURFACE PLASMON RESONANCE (LSPR) BERBASIS SERAT OPTIK MENGGUNAKAN MATERIAL AU/MGO UNTUK DETEKSI PROTEIN CFP-10 MYCOBACTERIUM TUBERCULOSIS

• Main Author: Marlia Subekti, Dhika
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/86699
• Institution: Institut Teknologi Bandung

Tuberculosis (TB) is a dangerous disease caused by the bacteria Mycobacterium Tuberculosa (Mtb). It can be transmitted through the air, disrupting the respiratory system in humans. That's why to prevent the epidemics, technology that is able to detect bacteria as early and effectively as possible is needed. Optical fiber-based localized surface plasmon resonance (LSPR) biosensor is a promising detection method that utilizes the phenomenon of plasmon resonance on metal surfaces guided via optical fiber to detect biomolecules with high sensitivity, low cost, minimal sample requirements, effective portability, and flexibility. However, to increase the sensitivity of the sensor, the modification can be made by adding sensing material to the surface of the optical fiber, which has been coated with a metal layer. Magnesium oxide (MgO) material is an inorganic material that has a large surface area, a large pore diameter, and has a plasmonic effect, so this material has the potential to be modified in fiber optic-based SPR biosensors on gold material to increase the sensitivity of sensor detection. In this study, a fiber optic-based LSPR biosensor was modified using Au/MgO to detect CFP-10 Mycobacterium Tuberculosa. The Au NPs were synthesized using 1 wt% trisodium citrate as much as 4 mL, 5 mL, and 6 mL, respectively named Au1, Au2, and Au3. While MgO material was synthesized using different PH levels, such as pH 10, 11, and 12, respectively named MgO1, MgO2, and MgO3. Based on the UV-Vis results on Au NPs, it shows absorption at a wavelength of 515 nm - 520 nm. Meanwhile, based on the XRD results on MgO, the crystallinity of MgO has high purity. SEM morphology results on MgO for each pH variation show changes in morphology and particle size, with flower-like MgO morphology producing the highest surface area of 89 m²/g and an average pore diameter of 37 nm. The MgO synthesis product was measured in SPR on optical fibers that had been coated with Au NPs with optimization using 0.1 mg/mL Bovine Serum Albumin (BSA). The results obtained a wavelength shift of 50 nm from bare Au to Au1/MgO3. Hasil optimasi terbaik tersebut dilakukan fungsionalisasi dengan antibodi CFP-10 lalu diujikan untuk mendeteksi protein CFP-10 dengan variasi konsentrasi 60, 100, 150, 250, dan 500 ng/mL From the concentration variation, the limit of detection (LOD) was obtained at 0.7 ng/mL, with a sensor sensitivity of 2.53. From this study, it was proven that MgO can significantly improve the performance of the LSPR biosensor. Therefore, the Au/MgO/CFP-10Ab LSPR biosensor based on optical fiber can be developed as a detection technology for CFP-10 Mtb protein in monitoring and diagnosing tuberculosis. Keywords: localized surface plasmon resonance (LSPR) biosensor, Fiber Optic, MgO, Au NPs, tuberculosis, CFP-10 ?