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Muhammad Fathurrahman
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Helium: Journal of Science and Applied Chemistry
Published by Universitas Pakuan
ISSN : 27761711     EISSN : 27764508     DOI : https://doi.org/10.33751/helium.v4i2
Core Subject : Science, Social, Engineering,
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Environmental Science Materials Science & Nanotechnology
Helium: Journal of Science and Applied Chemistry is a peer-reviewed journal on chemistry that encompasses all branches of chemistry (Analytical Chemistry, Biochemistry, Physical Chemistry, Inorganic Chemistry, and Organic Chemistry) and applied chemistry (Material Chemistry, Environmental Chemistry, Natural Products Chemistry, Computational Chemistry, etc.), except educational chemistry.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 25 Documents
 1   2   3 
Green Synthesis and Formation of Silica Nanoparticles Based on Natural Spondias mombin Leaf Extract for Renewable Energy Materials Armi Wulanawati; Yoki Yulizar; Sri Mulijani
Helium: Journal of Science and Applied Chemistry Vol. 6 No. 1 (2026): Helium: Journal of Science and Applied Chemistry
Publisher : Study Program of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/helium.v6i1.37

Abstract

Silica is an abundantly available material, with applications including renewable energy materials (fuel cells). Silica has been produced using natural materials (green synthesis) to form smaller and more stable particles, primarily due to the influence of secondary metabolites such as those contained in the leaf of Spondias mombin, a species of flowering plants from Lannea coromandelica (Houtt.) Merr and the family Anacardiaceae. The characteristics of silica nanoparticles obtained by green synthesis using the Spondias mombin leaf in a water fraction at 0,6 % were identified using XRD, FTIR, PSA, TGA, SEM, and TEM. Based on the XRD pattern and SEM/TEM images, the nanoparticle is amorphous and has a particle size of 20-30 nm, smaller than that of its precursor, which is 37.6 nm. There are Si-OH and Si-O-Si groups in the FTIR spectrum as an indication of the interaction between silica nanoparticles and secondary metabolites, and the zeta potential based on PSA is -45.9 mV. This indicates that silica nanoparticles have good stability and are supported by high thermal stability based on the results of the TGA analysis. This is correlated with its use as a material composite in renewable energy (fuel cells).
Characterization of Lipolytic Activity from Nyamplung (Calophyllum inophyllum L.) Seeds Lalu Rudyat Telly Savalas; Mukhtar Haris; Eka Junaidi; Saprizal Hadisaputra; Yunita Arian Sani Anwar; Lalu Anugrah Dimas Juniarly
Helium: Journal of Science and Applied Chemistry Vol. 6 No. 1 (2026): Helium: Journal of Science and Applied Chemistry
Publisher : Study Program of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/helium.v6i1.42

Abstract

Lipases are biocatalysts widely utilized in industrial and biotechnological processes due to their ability to catalyze the hydrolysis and synthesis of ester bonds. The search for novel lipase sources from plant materials continues to attract attention, particularly for sustainable and eco-friendly enzyme production. This study aims to isolate and characterize lipase from Nyamplung (Calophyllum inophyllum L.) seeds. The enzyme was extracted from germinated seeds and subjected to activity assays under varying temperature, pH, and germination length conditions. The highest lipase activity was obtained at 35 °C and pH 7.5, with an activity of 0.92 U/mL. The maximum activity was observed after 15 days of imbibition, reaching 1.06 U/mL. Protein characterization through SDS-PAGE revealed multiple bands with molecular weights of ~28, ~21 and ~19 kDa, indicating the presence of isoenzymes or subunit structures. These results suggest that Nyamplung seed lipase exhibits suitable catalytic properties for biotechnological applications. The enzyme’s moderate temperature and neutral pH optima make it a potential candidate for use in food and oleochemical industries.
Comparative Study of Functional Monomers and Crosslinkers in the Synthesis of Molecularly Imprinted Polymers for Selective Removal of Bisphenol A Lasmaryna Sirumapea; Tri Saputra Tambunan; Maharani Utami; Erjon; Arie Firdiawan; Fitria Puspita
Helium: Journal of Science and Applied Chemistry Vol. 6 No. 1 (2026): Helium: Journal of Science and Applied Chemistry
Publisher : Study Program of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/helium.v6i1.48

Abstract

Bisphenol A (BPA) is an endocrine-disrupting compound associated with documented environmental and health risks. This study evaluates and compares two distinct Molecularly Imprinted Polymer (MIP) architectures synthesized via bulk polymerization for selective BPA adsorption. System A utilized Methacrylic Acid (MAA) crosslinked with Ethylene Glycol Dimethacrylate (EGDMA), while System B employed Acrylamide (AM) with Trimethylolpropane Trimethacrylate (TRIM). FTIR spectroscopy confirmed template-monomer hydrogen bonding, while SEM revealed a porous morphology for System A compared to the dense surface of System B. Batch adsorption results showed that System A achieved a higher maximum capacity (Qmax = 14.74 mg/g) and imprinting factor (IF = 7.96) than System B (Qmax = 9.1 mg/g; IF = 3.33). These findings are attributed to the hydrogen-bonding affinity of MAA and enhanced site accessibility within the EGDMA matrix. Conversely, System B exhibited a higher selectivity coefficient (α = 4.1) against paracetamol than System A (α = 3.04), reflecting the influence of TRIM-induced rigidity on cavity fidelity. These findings indicate that the AM-TRIM system provides higher selectivity, while the MAA-EGDMA system demonstrates higher adsorption capacity for potential environmental applications.
Tuning Surface Wettability and Porosity of ZnO/Geopolymer Composite Membranes from Coal Fly Ash through H₂O₂ as Pore-Forming Agent Rendy Muhamad Iqbal; Siswo Siswo; Erwin Prasetya Toepak; Hamzah Fansuri; Muhammad ‘Adli Nor Azman; Yusuf Wibisono; Sri Wardhani; Deni Shidqi Khaerudini
Helium: Journal of Science and Applied Chemistry Vol. 6 No. 1 (2026): Helium: Journal of Science and Applied Chemistry
Publisher : Study Program of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/helium.v6i1.51

Abstract

The development of geopolymer membranes from industrial by-products offers a sustainable approach for water purification. In this study, ZnO/geopolymer membranes were prepared from coal fly ash, with hydrogen peroxide (H2O2) used as a pore-forming agent to regulate porosity and surface wettability. The influence of H2O2 concentration (0-6 wt%) on membrane physicochemical properties was systematically evaluated. FTIR analysis confirmed the formation of sodium aluminosilicate hydrate (N-A-S-H) gel and the incorporation of ZnO through the presence of Si-O-Zn and Zn-O bands. SEM images showed that increasing H2O2 concentration changed the initially dense structure into a rougher and more porous surface due to oxygen bubble generation during curing. ZnO addition enhanced surface roughness and functionality, while H2O2 improved pore connectivity. The water contact angle decreased from 21.63° in the pristine geopolymer to below 15° in the membrane with 6 wt% H2O2, indicating greater hydrophilicity. Porosity also increased from about 10% to 50%. These results demonstrate that ZnO incorporation combined with controlled H2O2 addition effectively tailors membrane wettability and pore structure, making the composite promising for sustainable water filtration.
Green Synthesis of Silver Nanoparticles Using Basilicum polystachyon Leaf Extract and Their Antibacterial Activity Against Staphylococcus aureus Diyah Lailatul Agustin; Suyatno Sutoyo; Radita Yuniar Arizandy; Wahyu Setyarini
Helium: Journal of Science and Applied Chemistry Vol. 6 No. 1 (2026): Helium: Journal of Science and Applied Chemistry
Publisher : Study Program of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/helium.v6i1.80

Abstract

AgNPs are nanomaterials with significant potential as antibacterial agents and can be synthesized in an environmentally friendly manner using plant extracts. This study aims to synthesize AgNPs using B. polystachyon leaf extract as a bioreductant and evaluate their antibacterial activity against S. aureus. The synthesis was performed by mixing B. polystachyon leaf extract with a 0.01 M AgNO₃ at volume ratios of 1:1, 1:2, 1:3, and 1:4, followed by pH optimization in the range of pH 8–11. The synthesized AgNPs were characterized using UV–Vis spectrophotometry, FTIR spectroscopy, PSA, and XRD. Antibacterial activity was evaluated using the disk diffusion method. The results showed that optimal synthesis conditions were achieved at a volume ratio of 1:4 and a pH of 11. The UV–Vis spectrum of the synthesized AgNPs exhibited a maximum absorption peak at 412 nm. FTIR analysis revealed the presence of O–H, aromatic C=C, and C–O bonds. The average particle size was 58.79 nm (PDI = 0.29). The XRD pattern confirmed the formation of crystalline silver.  The AgNPs inhibited the growth of S. aureus, with an inhibition zone diameter of 26.51 mm (very strong). Therefore, the synthesized AgNPs have the potential to be developed as antibacterial agents.

Page 3 of 3 | Total Record : 25

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