Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Chemistry

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 601 - 630 of 33111

Full-Text Articles in Physical Sciences and Mathematics

Understanding The Fidelity And Specificity Of Dna Polymerase I, Bill R. Miller Iii, Andrew V. Yeager, Jake A. Collins, Alexis Blake, Elise Tate, Carol A. Parish, Eugene Y. Wu Dec 2025

Understanding The Fidelity And Specificity Of Dna Polymerase I, Bill R. Miller Iii, Andrew V. Yeager, Jake A. Collins, Alexis Blake, Elise Tate, Carol A. Parish, Eugene Y. Wu

Chemistry Faculty Publications

High-fidelity DNA polymerases employ complex mechanisms to catalyze template-dependent DNA synthesis while quickly discarding mismatches. Atomic-level structural details about short-lived states during nucleotide discrimination are necessary to gain insight into the kinetic checkpoints that contribute to fidelity. We performed microsecond molecular dynamics simulations of DNA polymerase I, large fragment, from Bacillus stearothermophilus (Bacillus fragment, or BF) in complex with a template guanine and a mismatched thymidine triphosphate to observe the early events in the process of selection against a mismatch. Although the nucleobases formed a wobble base pair early, the mismatched pair was blocked from fully entering the active site …


Detection Of Ultra-Trace Levels Of Copper In Seawater Using A Bare Gold Microwire Electrode And A Portable Digital Voltammeter, Luke M. Brosnan, Wade Lonsdale, Paul Pringle, Paul Lewtas, Samantha Ridgway, Sebastien Allard, Magdalena Wajrak Dec 2025

Detection Of Ultra-Trace Levels Of Copper In Seawater Using A Bare Gold Microwire Electrode And A Portable Digital Voltammeter, Luke M. Brosnan, Wade Lonsdale, Paul Pringle, Paul Lewtas, Samantha Ridgway, Sebastien Allard, Magdalena Wajrak

Research outputs 2022 to 2026

The accumulation of biomass on ship hulls (biofouling) can greatly decrease their fuel efficiency. Many antifouling coatings contain copper as a biocidal agent, which can be released during hull cleanings and is of particular concern when cleaning the hulls in situ (i.e., without dry docking). Previously established voltammetric methods for the detection of copper in seawater using a gold microwire electrode have been modified and adapted to a portable on-site voltammetric technique. Notable differences from previous voltammetric methods include the use of linear sweep voltammetry, analysis under atmospheric conditions, alternating the potential during the deposition period and the use of …


Physicochemical, Pharmacognostic Standardisation And Phytochemical Analyses Of The Homoeopathic Drug Justicia Adhatoda, Bibaswan Biswas, Satish Patel, Digvijay Verma, Satyajit Maity, Shilpi Singh, Paulami Majumdar, Narasimha Kumar Gv Dec 2025

Physicochemical, Pharmacognostic Standardisation And Phytochemical Analyses Of The Homoeopathic Drug Justicia Adhatoda, Bibaswan Biswas, Satish Patel, Digvijay Verma, Satyajit Maity, Shilpi Singh, Paulami Majumdar, Narasimha Kumar Gv

Indian Journal of Research in Homoeopathy

Background: Justicia adhatoda (J. adhatoda), also well known as Vasaka in India is a medicinal plant chiefly used to treat respiratory ailments in traditional and alternative medical systems. Objective: This study aimed to establish the physicochemical, pharmacognostic, and phytochemical standardisation parameters of the drug. The study involved the measurement of physicochemical parameters and chemical profiling of the raw drug. The chemical characteristics of the in-house mother tincture (prepared from in-house raw drug) and commercial mother tinctures available in India were also evaluated to assess the quality of commercially available mother tinctures. Materials and Methods: The present study …


Two Members Of The Editorial Board Of Journal Electrochemistry, Kai Wu Elected As An Academician Of The Chinese Academy Of Engineering And Yi Cui A Foreign Academician Of The Chinese Academy Of Sciences, Editorial Office Of J.Electrochem. Dec 2025

Two Members Of The Editorial Board Of Journal Electrochemistry, Kai Wu Elected As An Academician Of The Chinese Academy Of Engineering And Yi Cui A Foreign Academician Of The Chinese Academy Of Sciences, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Electrochemical Characterization And Modulation Of Biological Processes, Yue-Qi Li, Wei-Hua Huang, De-Chen Jiang, Bao-Hong Liu, Bin Su, Yang Tian, Jing-Juan Xu, Ping Yu, Feng Zhao, Huang-Xian Ju, Jing-Hong Li Dec 2025

Electrochemical Characterization And Modulation Of Biological Processes, Yue-Qi Li, Wei-Hua Huang, De-Chen Jiang, Bao-Hong Liu, Bin Su, Yang Tian, Jing-Juan Xu, Ping Yu, Feng Zhao, Huang-Xian Ju, Jing-Hong Li

Journal of Electrochemistry

Electrochemical processes lie at the core of biological function, governing energy transduction, metabolic flux, and molecular signaling. Recent advances in electrochemical science now allow these processes to be probed and controlled with unprecedented spatial, temporal, and chemical resolution. In this review, we present an integrated framework that progresses from fundamental mechanisms to analytical technologies and functional modulation. We begin by outlining electron transfer pathways in mitochondrial respiration, microbial extracellular electron transfer, and DNA- and protein-based charge conduction, followed by the principles of photon-electron conversion in photosynthesis and the central role of redox equilibrium in coordinating cellular responses. We then highlight …


A Novel Electrolyte Pyridine Additive For Enhancing Cycle Life Of Lithium-Ion Batteries, Peng-Cheng Wang, Ding-Chang Li, Jun-Tao Li, Guang-Bo Lu, Shi-Wen Wang Dec 2025

A Novel Electrolyte Pyridine Additive For Enhancing Cycle Life Of Lithium-Ion Batteries, Peng-Cheng Wang, Ding-Chang Li, Jun-Tao Li, Guang-Bo Lu, Shi-Wen Wang

Journal of Electrochemistry

Lithium-ion (Li-ion) battery using a graphite (Gr.) anode and a lithium iron phosphate (LiFePO4, LFP) cathode (Gr.||LFP) has been widespread in energy storage. To match the warranty period of energy storage systems, the lifespan of this kind of Li-ion battery, not only under room temperature but also under relatively high temperature, is critical. Exploration of functional electrolyte additive provides an efficient approach to address this issue. This study reports the usage of pyridine (Py) as a new electrolyte functional additive for Gr.||LFP. In the first cycle, it was found that Py can be reduced before ethylene carbonate and …


Journal Of Electrochemistry Officially Indexed By Leading Oa Databases Oarl And Coaj, Editorial Office Of J.Electrochem. Dec 2025

Journal Of Electrochemistry Officially Indexed By Leading Oa Databases Oarl And Coaj, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Feature Column Of Journal Of Electrochemistry Nominated For 2025 Top 10 Famous Columns Of Fujian Provincial Newspapers And Periodicals, Editorial Office Of J.Electrochem. Dec 2025

Feature Column Of Journal Of Electrochemistry Nominated For 2025 Top 10 Famous Columns Of Fujian Provincial Newspapers And Periodicals, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere Dec 2025

Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere

Turkish Journal of Chemistry

Gold is abundant in nature, however, precise and reliable analytical methods for its detection are required stemming from its increasing prevalence in environmental, biological, and industrial systems, as well as the growing interest in understanding its function in living organisms and its effects on human health. This study investigates the use of biogenically synthesized silver nanoparticles (AgNPs) for the preconcentration and determination of gold ions prior to determination by UV-Vis spectrophotometry. AgNPs were synthesized by reducing silver nitrate through the use of an apricot kernel extract as both reducer and stabilizer agent. The colloidal yellowish AgNPs interacted with gold ions, …


Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee Dec 2025

Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee

Turkish Journal of Chemistry

Paclitaxel (Pac) is an important anticancer bioactive compound, and the availability of an accurate and robust analytical method for its quantification is of utmost importance. In this investigation, a novel, direct, and reliable spectrophotometric method has been proposed for the estimation of Pac via a complex formation reaction with osmium (Os). The method was based on the reaction of Pac with Os tetroxide, which produced a yellowish-brown complex. The resulting complex is soluble in water and displays a maximum absorption peak at 482 nm. The reaction conditions, including reactant concentration, pH, temperature, and reaction time, were optimized to obtain the …


Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal Dec 2025

Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal

Turkish Journal of Chemistry

This study used single-crystal X-ray diffraction, elemental analysis, infrared (IR) spectroscopy, theoretical nuclear magnetic resonance (NMR), and theoretical ultraviolet spectroscopy to characterize 3 newly synthesized crystalline compounds. Additionally, the nonlinear optical, highest occupied molecular orbital energies, lowest occupied molecular orbital energies, band gap, molecular electrostatic potential, and thermodynamic parameters of the 3 crystalline compounds were examined. The strong correlation between experimental IR spectra and theoretical NMR chemical shifts confirmed the accuracy of computational predictions. The molecular formulas of the 3 newly synthesized crystalline compounds, each containing different ligand molecules, were: C8H14O4·2(C6H4N2), C5H7N2·NCS, and Ni(CN)4·2(C5H7N2)·2(H2O) for compounds 1, 2, and 3, …


Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy Dec 2025

Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy

Turkish Journal of Chemistry

Novel coumarin–triazole–coumarin dyads were synthesized and characterized, and their α-glycosidase inhibitory activities were evaluated spectrophotometrically. Compound 4e exhibited the most pronounced inhibitory effect, with an IC50 value of 38.98 ± 0.77 μM. The IC50 values for 4d and 4a were 93.55 ± 1.70 μM and 95.04 ± 3.55 μM, respectively. The Lineweaver–Burk plot showed that 4e inhibited α-glycosidase in a mixed type. In addition, the Ki value obtained from the Dixon plot was 19.95 ± 0.15 μM for α-glycosidase.


Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz Dec 2025

Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz

Turkish Journal of Chemistry

This study investigates the extraction behavior of Y³⁺ ions using a Multi-Dropped Liquid Membrane (MDLM) system that employs di(2-ethylhexyl) phosphoric acid (D₂EHPA) as the carrier ligand. The focus is on the system’s ability to transport ions between aqueous phases selectively. The extracted complex was analyzed spectrophotometrically via ultraviolet–visible (UV–Vis) measurements after complexation with 0.05% Arsenazo III. The aim of this study was to determine the influence of the optimum D₂EHPA carrier concentration, together with the pH and temperature conditions of the donor and acceptor phases, on the system’s extraction performance. Accordingly, a series of extraction experiments was performed at different …


Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay Dec 2025

Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay

Turkish Journal of Chemistry

The direct synthesis of boron nitride nanotubes (BNNTs) via chemical vapor deposition (CVD) in high-temperature furnaces remains highly challenging due to difficulties in optimizing key experimental parameters such as synthesis temperature and catalyst composition. These challenges often result in uncontrolled growth behavior, adversely affecting the quality and yield of the BNNTs. In this study, colemanite was effectively utilized as a boron source for the high-yield synthesis of directionally aligned BNNTs. The synthesis was carried out using a CVD method that used a dual-catalyst system comprising Fe2O3 and MgO in conjunction with a silicon carbide template under high-temperature conditions. The resulting …


Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat Dec 2025

Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat

Turkish Journal of Chemistry

This study highlights the potential of organometallic carbonyl complexes as selective markers for biomolecules, enabling sensitive infrared (IR) detection. The regio- and stereoselective coupling of N-acetylhistamine, a histidine analogue, with the precursor complex 1 [Fe(CO)₃(1,4-η⁵-N-pyridiniocyclohexa-1,3-diene)] BF₄ affords the labeled complex 3 [Fe(CO)₃(1,4-η⁵-N-acetylhistaminocyclohexa-1,3-diene)]. X-ray diffraction (XRD) confirms the exo stereochemistry and reveals a rigid, well-defined architecture. IR and 1H nuclear magnetic resonance spectroscopic studies combined with IR-monitored acid–base titration demonstrate the complex’s stability in aqueous media between pH 5 and 8, alongside a modest increase in basicity relative to the free ligand. These findings establish the Fe(CO)₃ moiety as a robust …


New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş Dec 2025

New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş

Turkish Journal of Chemistry

A series of novel bis-piperazine derivatives (2a–2f) were synthesized and structurally characterized via Fourier transform-infrared and nuclear magnetic resonance spectroscopic techniques. Their gamma-ray shielding efficiencies were investigated through simulations on the Monte Carlo-based Geant4-GATE platform, and the results were benchmarked against data obtained from the XCOM and Phy-X software. A simulation model incorporating an NaI scintillation detector and a point gamma source was developed. Key shielding parameters, including mass attenuation coefficient, linear attenuation coefficient, half-value layer, and mean free path (MFP), were evaluated at gamma energies of 80, 120, 662, 1173, and 1332 keV. Additionally, the energy absorption buildup factor …


Structural Categorization And Identification Of Electrostatic Interactions In Two Proposed Human Serum Albumin Dimerization Patterns And Dipyridamole Interaction, Haluk Çeti̇nok, Veyi̇s Karakoç, Erol Erçağ, Yusuf Meli̇h Şekerer, Hasan Demi̇rci̇ Dec 2025

Structural Categorization And Identification Of Electrostatic Interactions In Two Proposed Human Serum Albumin Dimerization Patterns And Dipyridamole Interaction, Haluk Çeti̇nok, Veyi̇s Karakoç, Erol Erçağ, Yusuf Meli̇h Şekerer, Hasan Demi̇rci̇

Turkish Journal of Chemistry

Human serum albumin (HSA) is a ubiquitous, multifunctional protein responsible for the systemic distribution of both endogenous metabolites and exogenous pharmaceuticals. Its inherent properties, particularly its ability to seep into tissues and its multiple ligand-binding sites, have rendered HSA an attractive vehicle for nanoparticle-based drug delivery systems, particularly for cancer targeting. In this study, we present high-resolution crystallographic data revealing two distinct dimerization patterns of HSA (Protein Data Bank [PDB] ID: 9V61) obtained under high-concentration crystallization conditions, along with results from dipyridamole docking. Both dimer types demonstrate extensive interface areas and a significant number of electrostatic interactions. Comparative analysis with …


Synthesis, Characterization, Antimicrobial, Antioxidant, And Antiinflammatory Evaluation And Molecular Docking Studies Of N-((2-Hydroxy-3-(2-(Substitutedbenzylidene)Hydrazine-1-Carbonyl)Naphthalen-1-Yl)(3-Nitrophenyl/3,4-Dimethoxyphenyl)Methyl)Acetamide Derivatives, Shikha Kamboj, Alka Yadav, Samridhi Thakral, Rekha Tanwar, Sunil Kumar, Vikramjeet Singh Dec 2025

Synthesis, Characterization, Antimicrobial, Antioxidant, And Antiinflammatory Evaluation And Molecular Docking Studies Of N-((2-Hydroxy-3-(2-(Substitutedbenzylidene)Hydrazine-1-Carbonyl)Naphthalen-1-Yl)(3-Nitrophenyl/3,4-Dimethoxyphenyl)Methyl)Acetamide Derivatives, Shikha Kamboj, Alka Yadav, Samridhi Thakral, Rekha Tanwar, Sunil Kumar, Vikramjeet Singh

Turkish Journal of Chemistry

Hydrazone chemistry has become important and plays a key role in the development of organic compounds. Hydrazones can be useful pharmacophores for creating novel derivatives, owing to their broad range of activities. In this study, a series of N-((2-hydroxy-3-(2-(substitutedbenzylidene)hydrazine-1-carbonyl)naphthalen-1-yl)(3-nitro-phenyl/3,4-dimethoxyphenyl)methyl)acetamide derivatives were prepared, characterized by FTIR, 1H-NMR, 13C-NMR, and mass spectroscopy, and evaluated for their antimicrobial, antiinflammatory, and antioxidant activities along with in silico studies. The substituted derivatives were synthesized by the reaction of acetonitrile, chlorosulphonic acid, and substituted benzaldehyde with the hydrazones. The antimicrobial evaluation showed that compound 3i had more antimicrobial potential than the other tested molecules. Compound 3j …


Enhancing Analytical Performance Of Tyrosinase-Based Sensors With Nanoparticles For Detection Of Isoproterenol, Aysel Oktay, Sevi̇nç Kurbanoğlu, Gülsüm Gündoğdu, Cem Bülent Üstündağ, Frieder W. Scheller, Aysu Yarman Dec 2025

Enhancing Analytical Performance Of Tyrosinase-Based Sensors With Nanoparticles For Detection Of Isoproterenol, Aysel Oktay, Sevi̇nç Kurbanoğlu, Gülsüm Gündoğdu, Cem Bülent Üstündağ, Frieder W. Scheller, Aysu Yarman

Turkish Journal of Chemistry

In this work, electrochemical biosensors utilizing tyrosinase (Tyr) for the detection of the nonselective beta-adrenergic agonist isoproterenol (ISO) are presented. Three different configurations for immobilizing Tyr on a graphite electrode (GE) are compared: (1) GE modified with poly(diallyldimethylammonium chloride) (PDADMAC), PDADMAC/Tyr/GE; (2) PDADMAC combined with iridium nanoparticles (IrNPs) in a stepwise preparation, resulting in PDADMAC/IrNPs/Tyr/GE; and (3) a composite of PDADMAC and IrNPs mixed with Tyr at a 1:1 (v:v), forming PDADMAC/(IrNPs-Tyr)/GE. Surface morphology was characterized using scanning electron microscopy (SEM). Cyclic voltammetry (CV) and amperometry were applied to characterize the biosensor’s performance. Within the linear range of 5 μM …


Effects Of Π-Rich Solvents And Nickel And Cobalt Dopants On The Synthesis And Properties Of Cesium Lead Halide Nanocrystals, Tsung-Hsing Chiang Dec 2025

Effects Of Π-Rich Solvents And Nickel And Cobalt Dopants On The Synthesis And Properties Of Cesium Lead Halide Nanocrystals, Tsung-Hsing Chiang

Dissertations - ALL

Colloidal semiconductor nanocrystals feature unique properties like quantum confinement, tunable band gaps, and high surface-to-volume ratio; and have been proven as prominent materials in applications such as light-emitting diodes, sensors, lasers, solar cells, etc. Optoelectronic properties of semiconductor nanocrystals are highly associated with their sizes, morphologies, and compositions. Understanding the growth mechanism can lead to the ability to control the size, morphology, and composition of nanocrystals. In this thesis, growth and b-site doping of perovskite, cesium lead halide (CsPbX3), nanocrystals are discussed. Solvent effects in the growth of cesium lead bromide were first investigated from the aspect of plumbates in …


Exploring The Chemical And Biological Foundations Of Protein Lipidation Through Functional And Computational Studies, Andrea Sprague-Getsy Dec 2025

Exploring The Chemical And Biological Foundations Of Protein Lipidation Through Functional And Computational Studies, Andrea Sprague-Getsy

Dissertations - ALL

Post-translational modifications (PTMs) are essential for the diversification of the human proteome. Prenylation is a PTM defined by the addition of a 15-carbon or 20 carbon isoprenoid group by FTase and GGTase-I, respectively, onto a cysteine near the C-terminus of proteins. This modification is the first step within the prenylation pathway where proteolysis and carboxymethylation occur afterwards, aiding in proteins localization to the cellular membrane. These prenyltransferases canonically recognize a “CaaX” box motif which has been determined through biochemical and structural studies. Recently, sequences following the C(x)3X and Cxx patterns have been shown to be prenylated as well as an …


Variations In Physicochemical Properties, Microbiological Profiles, And Nutrient Dynamics In The Temi River, Arusha, Tanzania: Sources And Implications, Aldo J. Kitalika Dec 2025

Variations In Physicochemical Properties, Microbiological Profiles, And Nutrient Dynamics In The Temi River, Arusha, Tanzania: Sources And Implications, Aldo J. Kitalika

Tanzania Journal of Science

This study thoroughly investigates the physicochemical properties, microbiological profiles, and nutrient dynamics of the Temi River in Tanzania. The sources and implications of fluctuations in dissolved organic carbon (DOC) and nutrients during the wet and dry seasons are carefully analysed. Water samples were collected from various geographically referenced points along the river, and analyses were performed using the APHA Standard Methods for Water and Wastewater Testing. The results show that most parameters increased downstream in both seasons, with the highest DOC levels reaching 352.11 mg/L in the wet season, followed by a significant decrease to 126.00 mg/L during the dry …


Enzyme-Free Colorimetric Sensing Of Glucose Using Silver Nanoparticles With A Green Stabilizing Agent From Capsicum Chinense Jacq Extract, Boyfannie Ivan Putra, Hermin Sulistyarti, Muhammad Mashuri Utama, Aura Ananda Haryanto, Rurini Retnowati, Mohamad Rafi, Akhmad Sabarudin Dec 2025

Enzyme-Free Colorimetric Sensing Of Glucose Using Silver Nanoparticles With A Green Stabilizing Agent From Capsicum Chinense Jacq Extract, Boyfannie Ivan Putra, Hermin Sulistyarti, Muhammad Mashuri Utama, Aura Ananda Haryanto, Rurini Retnowati, Mohamad Rafi, Akhmad Sabarudin

Makara Journal of Science

Diabetes mellitus (DM) is a significant global health issue characterized by abnormal glucose levels in the human body. DM diagnostics are often based on invasive sampling from blood, which poses a potential risk of infection and tissue damage. Therefore, a non-enzymatic and non-invasive method for glucose monitoring is demanded as a simple alternative to glucose detection in urine samples. In this work, enzyme-free glucose determination is based on the formation of silver nanoparticles stabilized by Capsicum chinense Jacq extract (CCJ-AgNPs). Under alkaline conditions, glucose functions as a reducing agent for silver ions, and the extract acts as a stabilizer to …


Microplastic Degradation Using Laccase Enzyme From Trametes Hirsuta: In The Silico Study, Hanzhola Gusman Riyanto, Diana Sylvia Dec 2025

Microplastic Degradation Using Laccase Enzyme From Trametes Hirsuta: In The Silico Study, Hanzhola Gusman Riyanto, Diana Sylvia

Makara Journal of Science

Microplastics are a serious global problem that arises worldwide because of their widespread use. Exposure to microplastics can negatively affect human and environmental health. In this study, we used molecular docking methods with MOE software (version 2014.0901) to investigate the interaction between the laccase enzyme and several microplastic compounds as a preliminary study of microplastic degradation using enzymes. The Quantitative Structure Analysis Relationship (QSAR) analysis revealed that all microplastic ligands had higher Pa values than Pi, indicating that the laccase enzyme may be biologically active. The findings of the present study show that polyamide (PA) has the lowest binding energy …


Quantitative Structure-Activity Relationship, Pharmacokinetics, Drug-Likeness, Toxicity, And Molecular Docking Studies Of 4-N-(Methyl)-4-Aminoquinoline Derivatives As Antimalarial Compounds, Muhamad Jalil Baari, Devi Hardiyanti Dec 2025

Quantitative Structure-Activity Relationship, Pharmacokinetics, Drug-Likeness, Toxicity, And Molecular Docking Studies Of 4-N-(Methyl)-4-Aminoquinoline Derivatives As Antimalarial Compounds, Muhamad Jalil Baari, Devi Hardiyanti

Makara Journal of Science

Antimalarial drug resistance has encouraged various innovations to develop novel drug compounds that are effective, feasible, and safe, adhering to health standards. One way to do that is by observing and predicting the biological activity of drug compounds using quantitative structure–activity relationship (QSAR) analysis. In this study, QSAR analysis was conducted on the 4-N-(methyl)-4-aminoquinoline derivatives, which effectively inhibit the growth of Plasmodium falciparum as a source of malaria. The research stages involved molecular structure modeling, molecular geometry optimization using the AM1 semi-empirical method, and QSAR descriptor calculations, including electronic (atomic charges (q), HOMO and LUMO energies, polarizability (α), …


Suitability Of Mobile Phase Recycling For Methylxanthine Quantification In Coffee Samples Using Hplc, Kaitlin O’Keeffe, Marcos Mariano, Brian Murphy Dec 2025

Suitability Of Mobile Phase Recycling For Methylxanthine Quantification In Coffee Samples Using Hplc, Kaitlin O’Keeffe, Marcos Mariano, Brian Murphy

SURE Journal: Science Undergraduate Research Experience Journal

Caffeine, theobromine and theophylline fall under a drug class known as methylxanthines. These three compounds are of major interest in the food industry due to their presence in popular foods and beverages such as tea, coffee, and chocolate. As these compounds can cause physical and mental stress at high dosages, their quantification is essential to ensure product safety and quality. Here, we describe an eco-friendly HPLC method developed to quantify the amount of these analytes in coffee samples sourced across the SETU Waterford, Cork Road campus. Using an isocratic mixture of water and methanol, a mobile phase recycling approach was …


Salicylic Acid Heterocyclic Derivatives: Chemical Synthesis And Biological Activity, Rawaa Hefdi Zaooli, Marwa Abdulameer Mseer, Amneen Mohammed Alsayegh Dec 2025

Salicylic Acid Heterocyclic Derivatives: Chemical Synthesis And Biological Activity, Rawaa Hefdi Zaooli, Marwa Abdulameer Mseer, Amneen Mohammed Alsayegh

Al-Bahir

Before a drug can be widely used, it must go through a long development process, starting from the discovery of the active ingredient and continuing with tests to confirm its safety and effectiveness. In this study, new olsalazine derivatives were synthesized, containing a fused morpholine-3-one ring and two five-membered heterocyclic rings (thiadiazole and oxadiazole). Common and readily available materials, such as salicylic acid (to prepare 2-hydroxy-5-nitrobenzoic acid) and inexpensive catalysts, were used to synthesize compounds from the first, 5,5'-(diazene-1,2-diyl)bis(2-hydroxy-3-nitrobenzoic acid) (A1), to the seventh, 6,6'-(diazene-1,2-diyl)bis(N-(4-(5-amino-1,3,4-oxadiazol-2-yl)phenyl)-3-oxo-3,4-dihydro-2H-benzo[b][1,4]oxazine-8-carboxamide) (A7).

Each compound was characterized by FT-IR and ¹H-NMR spectroscopy, along with physical properties such …


Energetics And Kinetics Of Alkali Ion Exchange In Analcime, Jinyi Liu, An T. Ta, R. Seaton Ullberg, Jean Wilfried Hounfodji, Michael Badawi, Hans Conrad Zur Loye, Simon R. Phillpot Dec 2025

Energetics And Kinetics Of Alkali Ion Exchange In Analcime, Jinyi Liu, An T. Ta, R. Seaton Ullberg, Jean Wilfried Hounfodji, Michael Badawi, Hans Conrad Zur Loye, Simon R. Phillpot

Faculty Publications

We employ density functional theory calculations to investigate the energetics and diffusion mechanisms of alkali metal ions (Na+, K+, Rb+, and Cs+) within the analcime framework. While Na+preferentially adsorbs at the center of the 8-member ring, DFT calculations show that larger ions, such as Cs+, occupy the center of the cage due to steric constraints. The computed exchange energies indicate that exchange of Na+by Cs+is thermodynamically favorable. Migration energy barriers, determined using the climbing image nudged elastic band method, show that Na+is …


Chaos Engineering In Multi-Gigahertz Solid-State Lasers: A Novel Approach To Optoelectronic Control, Mikhail V. Gorbunkov, Yulia Ya. Maslova, Yulia A. Sinichkina Dec 2025

Chaos Engineering In Multi-Gigahertz Solid-State Lasers: A Novel Approach To Optoelectronic Control, Mikhail V. Gorbunkov, Yulia Ya. Maslova, Yulia A. Sinichkina

Karbala International Journal of Modern Science

This paper presents a comprehensive study of a multi-gigahertz chaotic generator of light pulses based on solid-state laser sources, including fiber lasers, governed by carefully designed positive and negative feedback loops. It harnesses the inherent nonlinear dynamics within a solid-state laser controlled by a combination of two inertial feedback loops, enabling the realization of complex chaotic behavior, including the logistic map scenario, under moderate amplification conditions. The laser system dynamics are rigorously investigated through theoretical modeling, employing a nonlinear map approach, and high-resolution picosecond simulations. The results of our numerical simulations highlight the efficacy of fast electro-optical feedback system with …


Unveiling The Anticancer Potential Of Syzygium Cumini: In Silico Insights Into Its Mechanistic Action Against Non-Small Cell Lung Cancer, Nur Sofiatul Aini, Win Darmanto Dec 2025

Unveiling The Anticancer Potential Of Syzygium Cumini: In Silico Insights Into Its Mechanistic Action Against Non-Small Cell Lung Cancer, Nur Sofiatul Aini, Win Darmanto

Karbala International Journal of Modern Science

Non-small cell lung carcinoma (NSCLC) is the most periodic type of lung cancer and the second most diagnosed cancer globally. Syzygium cumini is plant that extensively used in cuisine and traditional medicine. However, its potential for NSCLC treatment has not yet been elucidated. This study determined the potential of S. cumini as anti-NSCLC using in silico approaches. The in silico study was applied to perform active compound analysis, selection of target candidates, network pharmacology, functional annotation, molecular docking, and molecular dynamics simulation, respectively. Based on open source databases, S. cumini contained 115 compounds and 14 of them predicted to have …