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All Journal Jurnal Pendidikan Kimia (JPKim) Chemistry Indonesian Journal of Chemical Research JOURNAL OF CHEMICAL NATURAL RESOURCES (JCNaR) Jurnal Akademika Kimia
Marpongahtun, Marpongahtun
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Biochemistry, Genetics & Molecular Biology Chemistry Education Engineering Environmental Science Materials Science & Nanotechnology

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 1 
Synthesis, Microstructure, Optical Properties, and Sensitive Amoxicillin Detection of Carbon Dots Lubis, Yuni Aldriani; Gea, Saharman; Lubis, Muhammad Frassetia; Pai, Woei Wu Larry; Marpongahtun, Marpongahtun
Indonesian Journal of Chemical Research Vol 13 No 1 (2025): Edition for May 2025
Publisher : Jurusan Kimia, Fakultas Sains dan Teknologi, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598/ijcr.2025.13-yun

Abstract

The detection of amoxicillin has been successfully carried out using C-dot fluorescence probes made from d-glucose and urea. The fluorescence probe has an intense bright blue emission under UV light at 395 nm and and depends on the excitation and depends on the excitation. Raman studies successfully showed a D peak at 1381 cm-1 and a G peak at 1586 cm-1 associated with graphitic and amorphous structures. The absorption peaks in UV-vis spectroscopy confirm transitions at 275 nm (π → π*) and 322 nm (n → π*) with the presence of conjugated C=C and carbonyl (C=O) functional groups. The results of the fluorescence test show a bright blue color, with its intensity measured at an excitation of 365 nm. This can be attributed to nitrogen incorporation on the surface of the C-dots derived from urea, resulting in a quantum yield of 54%. This fluorescence probe is highly sensitive in detecting amoxicillin, as evidenced by the successful detection of AMX at concentrations of 10–30 μM and a resulting LOD of 5.75443×10−7 nM. The microstructure shows a uniform size of C-dot nanoparticles, and C-dot modeling was created. C-dot probes have an LOD of 5.75443×10−7 nM, indicating high sensitivity in detecting AMX.
Exploring the Effect of Ethylenediamine Concentration on the Optical Properties of Carbon Dots Synthesized from Candlenut Shell Biomass Marpongahtun, Marpongahtun; Safhura, Tjut Siti; Siregar, Amir Hamzah
Journal of Chemical Natural Resources Vol. 7 No. 1 (2025): Journal of Chemical Natural Resources (JCNaR)
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jcnar.v7i1.20639

Abstract

Carbon dots are fluorescent nanomaterials with a size below 10 nm, known for their good optical properties, including fluorescence emission and biocompatibility which are very suitable for various applications, such as bioimaging, sensors and optoelectronics. This research aims to synthesize CDs and NCDs from candlenut shells as a biomass source using the hydrothermal method at 230°C for 6 hours with the addition of ethylenediamine (EDA) as a nitrogen dopant at concentrations of 4%, 8% and 12% (v/v). The study also evaluates the effect of varying EDA concentrations on the optical properties of CDs and NCDs. Based on the results, under 365 nm UV irradiation, all samples showed bluish green fluorescence. The results of UV-Vis analysis showed an absorption peak at a wavelength of 271 nm for CDs and additional absorption peaks at 274 nm and 324 nm for NCDs, corresponding to the π–π* and n–π* transitions, respectively. Increasing EDA concentration is associated with a gradual decrease in the absorption intensity of CDs and NCDs. The photoluminescence results showed the CDs emission peak at 494 nm with a quantum yield (QY) of 18% and the strongest fluorescence at 498 nm for NCDs 8% with the highest QY of 27%. The results of FTIR analysis showed -OH, C=O and C=N functional groups in all samples and additional -NH functional groups in the NCDs, indicating successful nitrogen incorporation.
Synthesis and characterization nitrogen-doped carbon dots from candlenut shells using hydrothermal and solvothermal methods Riska, Riska; Marpongahtun, Marpongahtun; Gea, Saharman
Jurnal Pendidikan Kimia Vol. 16 No. 1 (2024): April
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/jpkim.v16i1.56957

Abstract

Candlenut shells can be utilized as precursors for Carbon Dots (CDs) since new nanoscale materials have been proven using lignin, cellulose, hemicellulose, and carbon present in candlenut shells. A carbon substance smaller than 10 nm in size, CDs have special optical properties. This research focuses on the synthesis of CDs and Nitrogen Carbon Dot (NCDs) from hazelnut shell using urea passivation agent by hydrothermal and solvothermal methods, to determine the effect of solvent on the emission produced by CDs and NCDs. Hazelnut shell was carbonized at 300°C for 6 hours. The synthesis of CDs and NCDs was carried out at 220°C for 8 hours, then sonicated at 75°C for 30 minutes. The synthesis results were centrifuged at 5000 rpm for 30 minutes, filtered using Whatman No.42 filter paper. Analysis with a 365 nm UV lamp produced bluish green luminescence, brighter luminescence was shown in NCDs by solvothermal method. UV-Vis spectra showed absorbance peaks of 289-309 nm for CDs and 335-350 nm for NCDs. FTIR spectra of CDs and NCDs produced OH, CH, C=C, C=O, C-N, CO, and C-O-C functional groups. Photoluminescence analysis showed emission peaks of CDs and NCDs at 494 nm and 496 nm for hydrothermal method, for solvothermal method at 418 nm and 432 nm. CDs and NCDs with hydrothermal method showed higher intensity than with solvothermal method. The quantum yield values obtained were 11.4226% and 25.7419% and 10.2555% and 11.7473% for hydrothermal and solvothermal methods, respectively. Solvothermal method was effective for the synthesis of CDs and NCDs with brighter luminescence.
Impact of the Concentration Ethylenediamine on Optical Properties of Carbon Dots from Jengkol Peel (Archinendron pauciflorum) Prayugo, Aniza S.; Marpongahtun, Marpongahtun; Gea, Saharman
Jurnal Akademika Kimia Vol. 12 No. 1 (2023)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2023.v12.i1.pp20-25

Abstract

Carbon dots (CDs) are a new member of fluorescent nano carbons that have attracted attention because of their potential applications derived from their optical, chemical, and electrical properties. CDs from jengkol peel via the solvothermal method at 200 oC for 7 h with the addition of ethylenediamine (EDA) as a heteroatom dopant have been successfully carried out. This study aims to determine the effect of concentration EDA on the optical properties of CDs for the possible reason. The results revealed that the CDs solution has fluorescence properties; that bluish-green glow can be observed under ultraviolet radiation (365 nm). The UV - Vis absorption peaks did not depend on the CDs concentration, but the absorbance intensity decreased with increasing EDA concentration. The best fluorescence properties were possessed by 10 % EDA in CDs which produced λex/λem of 370 nm/518 nm, respectively, with a quantum yield of 42 %. The FTIR spectra of all samples showed that the CDs surface had functional groups such as carboxylic acids, hydroxyl, and amines. The obtained CDs have the potential to be used as heavy metal ion detectors, bioimaging, and antibacterial agents.
Degradation of Natural Rubber as Asphalt Mixes Modifier using UV-Ozone Light Ritonga, Irene I. C.; Tamrin, Tamrin; Marpongahtun, Marpongahtun
Jurnal Akademika Kimia Vol. 12 No. 2 (2023)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2023.v12.i2.pp78-85

Abstract

The elastic properties of natural rubber are indispensable in improving the physical properties of asphalt mixtures. However, the long natural rubber molecule chains make it difficult to modify with other polymeric materials, so it needs to be degraded. In this study, the authors succeeded in degrading natural rubber using a combination of UV light and ozone with the addition of an H2O2 initiator; from the FTIR data, it appears that there are peaks indicating vibrations of the C=O and –OH groups indicating that natural rubber chain termination has occurred. The addition of natural rubber to asphalt was carried out with several variations, namely 8; 10; 12; 14; 16 % (to asphalt content), from the results of the softening point and ductility test of the asphalt mixture explained that the addition of 12 % natural rubber was the most optimum mixture. This result explains that efforts to degrade natural rubber using the UV - ozone combination method can increase the optimum insertion of natural rubber into asphalt mixtures by up to 100 % from previous studies.
Co-Authors Amir Hamzah Siregar, Amir Hamzah Lubis, Muhammad Frassetia Lubis, Yuni Aldriani Pai, Woei Wu Larry Prayugo, Aniza S. Riska Riska Ritonga, Irene I. C. Safhura, Tjut Siti Saharman Gea Tamrin Tamrin