Article Per Year (5 Year)
p-Index From 2021 - 2026
0.408
P-Index
This Author published in this journals
All Journal JURNAL ATOMIK
Daniel -
Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Mulawarman
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Environmental Science

Published : 3 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 3 Documents
Search

 1 
SYNTHESIS OF METHYL MALATE THROUGH ESTERIFICATION REACTIONS USING METHANOL SOLVENTS AND INSITU REACTIONS WITH ACID CATALYSTS Eci Endang Sinulingga; Daniel -; Chairul Saleh; Agustina Rahayu Magdaleni
JURNAL ATOMIK Vol 5 No 1 (2020)
Publisher : Jurusan Kimia FMIPA UNMUL

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Research has been carried out on the synthesis of methyl malate through esterification reactions using methanol solvents and in situ reactions with acid catalysts. Esterification of malic acid was carried out with a ratio of methanol 1:3 to produce pale yellow methyl malate with a yield of 94.06%. The formed methyl malate then characterizes using the FT-IR instrument and tests its HLB value. The result of FT-IR analysis which will indicate that methyl malate has formed is that the carboxylic group from malic acid has been converted into an ester group from the esterification reaction. The wavenumber of the carboxylic group of malic acid is 1720.50 cm-1 and the ester group is the result of an esterification reaction at wave number 1735.93 cm-1, indicating that methyl malate has been formed. Furthermore, for the HLB value based on the results of the study obtained at 11.2, which indicates that methyl malate is included in the O / W emulsifier (Oil in Water).
SINTESIS DAN KARAKTERISASI NANOPARTIKEL PERAK TERMODIFIKASI GLUTATHIONE MENGGUNAKAN REDUKTOR NaBH4 Adrian Maulana Aditya; Daniel -; Noor Hindryawati
JURNAL ATOMIK Vol 10 No 2 (2025)
Publisher : Jurusan Kimia FMIPA UNMUL

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/ja.v10i2.1549

Abstract

Silver nanoparticles (AgNPs) possess remarkable properties that make them suitable for various applications in biomedical, environmental, and catalytic fields. This study focuses on the synthesis and characterization of glutathione-modified silver nanoparticles (AgNPs-GSH) using sodium borohydride (NaBH₄) as a reducing agent. The reduction of AgNO₃ by NaBH₄ produces elemental silver nanoparticles, as indicated by a color change to bright yellow due to the localized surface plasmon resonance (LSPR) phenomenon. The synthesized nanoparticles were stabilized using glutathione (GSH), which binds through thiol (-SH), amine (-NH₂), and carboxyl (-COOH) functional groups, enhancing the stability and biocompatibility of the AgNPs. UV-Vis spectroscopic analysis revealed a maximum absorbance at 408 nm, consistent with the optical properties of silver nanoparticles. Furthermore, particle size analysis indicated an average nanoparticle size of 1.271 nm, with some degree of agglomeration. These findings suggest the successful synthesis and functionalization of AgNPs-GSH with potential applications in nanobiotechnology.
PENURUNAN KADAR ASAM LEMAK BEBAS PADA MINYAK JELANTAH DENGAN MENGGUNAKAN ABU KALSINASI DARI BEBERAPA BAHAN ADSORBEN Rafi Firmana Hadyanto; Ritson Purba; Daniel -; Ade Shiva Rizki
JURNAL ATOMIK Vol 10 No 2 (2025)
Publisher : Jurusan Kimia FMIPA UNMUL

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/ja.v10i2.1563

Abstract

Cooking oil has a primary function as a heat transfer medium in food processing. Repeated use of cooking oil can reduce its quality, which is often referred to as used cooking oil. Many people use cooking oil repeatedly to save money without considering the impact. The purpose of this study was to determine the results of refining used cooking oil in terms of free fatty acid (FFA) levels through the adsorption method using calcined ash from several different types of adsorbents, namely chicken eggshells, Tegillarca granosa shells, zeolite, and bricks. Based on the results of the study, the results of the FFA content of the used cooking oil sample were 2.735%. The results of the FFA content of the used cooking oil sample after being adsorbed using calcined ash from chicken eggshells, blood cockle shells, zeolite, and bricks were 0.638%, 0.464%, 1.691%, and 0.921%, respectively. Of the four adsorbent materials, the type of adsorbent obtained is calcined blood cockle shell ash which is the most effective in reducing the ALB levels of used cooking oil samples, which is 83.03%. Then followed by chicken egg shells, which is 76.67%, bricks, which is 66.32%, and commercial zeolite, which is 38.17%.
Co-Authors Ade Shiva Rizki Adrian Maulana Aditya Eci Endang Sinulingga Magdaleni Agustina Rahayu Noor Hindryawati, Noor Rafi Firmana Hadyanto Ritson Purba Saleh, Chairul