การประยุกต์ใช้อนุภาคทองคำนาโนที่สังเคราะห์ได้จากวิธีการทางชีวภาพเพื่อเป็นตัวเร่งปฏิกิริยาการย่อยสลายสีย้อม

• Main Author: ศิรประภา เหล่ามูล
• Other Authors: สริสา ณ ป้อมเพ็ชร์
• Format: Senior Project
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 2020
• Subjects: อนุภาคนาโน; ทอง; เชื้อรา; Nanoparticles; Gold; Fungi
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:10904
• Institution: Chulalongkorn University

The synthesis of gold nanoparticles (AuNPs) using microorganisms such as bacteria, mushrooms, yeasts, fungi as well as their cell-free extracts has been trending in recent years. Fungi have gained popularity as sources for the biosynthesis because they can tolerate higher metal concentrations compared to bacteria do. Moreover, fungi generally secrete abundant extracellular enzymes and proteins that can reduce gold ion (Au³⁺) to gold nanoparticle (Au⁰: AuNP). The biosynthesis of AuNP is a low-cost process with less toxicity and great environmental friendliness. In this study, we synthesized AuNP from Aspergillus niger MSCU 0361 and evaluated its efficiency as a catalyst for dye degradation of methylene blue. The UV-visible spectroscopy result showed the maximum absorbance at 558 nm. The transmission electron microscope (TEM) micrograph displayed various shapes of AuNP such as sphere and cylinder, and a broad size distribution of AuNP was observed. The average size of AuNP reported by dynamic light scattering (DLS) was 60.74 nm. The zeta potential was -17.4 mV, indicating negative charge on the surface of AuNP. The catalytic activity of AuNP for methylene blue degradation was investigated by measuring maximum absorbance at 664 nm. The result showed that the control, which contained only ascorbic acid as a reducing agent, had better dye degradation efficiency than the reaction mixed with ascorbic acid and AuNP. However, to understand the mechanism behind the dye degradation using AuNP, further study is needed.