FUNGSIONALISASI NANOPARTIKEL SILIKA FLUORESEN MAGNETIK DENGAN ANGIOTENSIN-CONVERTING ENZYME II UNTUK DETEKSI SEVERE ACUTE RESPIRATION SYNDROME CORONAVIRUS 2 (SARS-COV-2)

• Main Author: Yovinanda Maulana, Muhammad
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/70312
• Institution: Institut Teknologi Bandung

<p align="justify">Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) causes a mysterious case of pneumonia called Coronavirus Disease 2019 (COVID-19). COVID-19 was declared a pandemic by the World Health Organization (WHO) on March 12 2020. The COVID-19 pandemic caused by SARS-CoV-2 has resulted in a serious health crisis. Therefore, a series of diagnostic strategies are needed for the community to be able to detect early exposure to the virus, prevent the spread of the virus, and map the spread of this virus. This research was conducted using an experimental method which was divided into six stages. The first stage is a literature study and the determination of the parameters used in the experiment. The second stage involved the synthesis of Fe-NP materials using the coprecipitation method and Fe-FSNP using the sol-gel method using various Rhodamine B dyes. The third stage was surface functionalization of Fe-FSNP with the ACE-2 enzyme as a receptor for SARS-CoV-2. In the fourth stage, the material is characterized to determine its structure, morphology and other properties. The fifth stage is the process of testing the sensor against the SARS-CoV-2 antigen. The final stage is report writing. This research aims to design a fluorescence labelbased optical biosensor for the detection of SARS-CoV-2 using ACE2- functionalized Fe-FSNP material. In general, optical biosensors are divided into two, namely label-free and label-based. Label-free is a method that detects signals from materials directly by interaction with transducers. Then, the label-based method is a method that uses labels for interaction with transducers. The label used is a material that has fluorescent or luminescent properties. Magnetic iron oxide nanoparticles (Fe-NP) were synthesized via ultrasonic coprecipitation and then formed into magnetic fluorescent silica nanoparticles (Fe-FSNP) via the sol-gel method. The source of silica used is silica by-product from geothermal power plants. Rhodamine B was chosen as a fluorescent dye in this study, and further dye variations were carried out to see the performance of the dye in magnetic nano fluorescent materials. This Fe-FSNP consists of a magnetic core and a silica shell which was confirmed from transmission electron microscopy (TEM) images. Surface functionalization of Fe-FSNP with angiotensin converting enzyme II (ACE2) as a bioreceptor was carried out through the hydrosylation method which was confirmed by Fourier transform infrared (FTIR) spectra. The ACE2 functionalized nanoparticles were then applied as a biosensing platform to detect the SARS CoV-2 antigen. Sample characterization in this study was used: X-Ray Diffactometer, Scanning Electron Microscope, Transmission Electron Microscope, Surface Area Analyzer, Vibrating Sample Magnetometer, Fourier Transform Infrared Spectroscopy and Spectrofluorometry. In this study, a test based on an analysis of fluorescent intensity was used to determine the performance of the SARS-CoV-2 sensor from the synthesized material. The fluorescent intensity of the material will be observed before detection and after detection, the phenomena that occur at both times will be observed and analyzed. It was reported that the fluorescent intensity value will be quenched when interacting with nucleobased. The phenomenon that occurs is fluorescence resonance energy transfer (FRET). FRET is a process in which non-radiated energy is transferred from an excited luminescent donor to a luminescent acceptor (quencher). In this study, certain receptors are used according to the target. The results of the SARS-CoV-2 literature study will react biologically with ACE2. Based on this phenomenon, ACE2 is used on the Fe-FSNP surface in order to capture the desired target. Then, the use of magnetic materials is also used to speed up the separation process during detection. The results show a response time of 30 minutes. The limit of detection (LoD) was calculated at 0.14 fg/mL with a linear range of 10-2 to 10-6 ????g/mL.