Jurnal Ilmu Fisika Vol. 15, No. 2, September 2023, pp. 91-105 ISSN: 1979-4657 (Print); 2614-7386 (Online) https://doi.org/10.25077/jif.15.2.91-105.2023 Attribution-NonCommercial 4.0 International http://jif.fmipa.unand.ac.id/ 91 Open Access Jurnal Ilmu Fisika Synthesis of Fluorescent Carbon Dots (CDs) Using Laser Ablation Method for Bioimaging Application Jumardin Jumardin 1 , Akhiruddin Maddu 2 , Kokoeh Santoso 3 , Isnaeni Isnaeni 4 1 Department of Physics, Faculty of Sciences and Technology, Alauddin State Islamic University of Makassar Gowa, 92113, Indonesia 2 Department of Physics, Faculty of Mathematics and Natural Sciences, IPB University, Bogor, 16680, Indonesia 3 Department of Anatomy, Physiology and Pharmacology, School of Veterinary and Biomedical, IPB University Bogor, 16680, Indonesia 4 Research Center for Photonics, National Research and Innovation Agency (Badan Riset dan Inovasi Nasional, BRIN) BJ Habibie Science and Technology Park, Banten 15314, Indonesia Article Info ABSTRACT Article History: Received January 17, 2023 Revised March 12, 2023 Accepted April 19, 2023 Published online May 06, 2023 Carbon Dots (CDs) were synthesized using laser ablation by focusing the laser beam on carbon (Tea) material in colloid (CH 3 ) for 3 hours. UV-Vis spectroscopic and fluorometric characterization showed absorption of the wavelength peaks caused by the control treatment and after laser ablation and coating using Poly Ethylene Glycol (PEG 400 ). The excitation and emission energies are formulations of CDs absorbance wavelength and fluorescence intensity. The absorbance coefficient is obtained based on the absorbance value of the cuvette thickness. The transmittance value (T) is obtained based on the absorption coefficient multiplied by 100%. CD fluorescence wavelength based on control parameters was 489 nm. After laser ablation was 496 nm, and after coating was 511 nm. CDs morphology and size characteristics are 4 nm to 10 nm based on TEM measurements. Fluorescence analysis for bioimaging applications on the luminescence intensity value of internalized blue CDs in zebrafish eye organs. The average intensity of CDs in the eye organs, gill, intestinal, dorsal, and tail injection points was 88.15 %, 91.58 %, 92.76 %, and 0.00 %. Copyright © 2023 Author(s) Keywords: Carbon dots Laser ablation Fluoresccent Bioimaging Corresponding Author: Jumardin Jumardin Email: jumardin.jumardin@uin- alauddin.ac.id 1. INTRODUCTION Carbon Dots (CDs) are zero-dimensional nanomaterials (Liang et al., 2020) in the carbon nano group with a size of less than 10 nm (Alkian et al., 2022). CDs exhibit stable photoluminescence, good biocompatibility (Dias et al., 2019), and low toxicity to various cells (Emam et al., 2017), and thus have potential as bioimaging materials (Li et al., 2020). Luminescence from CDs is the event of the appearance of visible light by a particular substance (Zhang et al., 2021) after absorption of radiant energy (Wang et al., 2009). A luminescence event is caused by electrons that absorb the radiant energy, and these electrons move to higher orbitals, exciting the material molecules into an excited state. The Fluorescence that occurs in CDs is due to the excited molecules returning to their ground state by releasing energy through the emission of photons. The Fluorescence of CDs is of great interest because it fluoresces in biological materials (living cells) and can be modified for biomedical applications (Phukan et al., 2022). They use this property in biomedical applications, Fluorescence for increased