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1.
Biophys Chem ; 311: 107272, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38824845

ABSTRACT

In the presented work, a study on the solubility and intermolecular interactions of l-serine and L-cysteine was carried out in binary mixtures of H2O + dimethylformamide (DMF), H2O + dimethylsulfoxide (DMSO), and H2O + acetonitrile (ACN) in the temperature range of T = 288.15 K to 308.15 K. l-serine exhibited the highest solubility in water, while L-cysteine was more soluble in water-DMF. The solvation process was assessed through standard Gibbs energy calculations, indicating the solvation stability order: water-ACN > water-DMSO > water-DMF for l-serine, and water-DMF > water-DMSO > water-ACN for L-cysteine. This study also explored the influence of these amino acids on solvent-solvent interactions, revealing changes in chemical entropies and self-association patterns within the binary solvent mixtures.


Subject(s)
Acetonitriles , Cysteine , Dimethyl Sulfoxide , Dimethylformamide , Serine , Solubility , Temperature , Water , Dimethyl Sulfoxide/chemistry , Serine/chemistry , Acetonitriles/chemistry , Water/chemistry , Cysteine/chemistry , Dimethylformamide/chemistry , Thermodynamics , Solvents/chemistry
2.
RSC Adv ; 14(18): 12829-12840, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38645531

ABSTRACT

A novel strategy was employed to create supramolecular metallogels incorporating Tb(iii) and Eu(iii) ions using benzene-1,3,5-tricarboxylic acid (TA) as a gelator in N,N-dimethylformamide (DMF). Rheological analysis demonstrated their mechanical robustness under varying stress levels and angular frequencies. FESEM imaging revealed a flake-like hierarchical network for Tb-TA and a rod-shaped architecture for Eu-TA. EDX analysis confirmed essential chemical constituents within the metallogels. FT-IR, PXRD, Raman spectroscopy, and thermogravimetric analysis assessed their gelation process and material properties, showing semiconducting characteristics, validated by optical band-gap measurements. Metal-semiconductor junction-based devices integrating Al metal with Tb(iii)- and Eu(iii)-metallogels exhibited non-linear charge transport akin to a Schottky diode, indicating potential for advanced electronic device development. Direct utilization of benzene-1,3,5-tricarboxylic acid and Tb(iii)/Eu(iii) sources underscores their suitability as semiconducting materials for device fabrication. This study explores the versatile applications of Tb-TA and Eu-TA metallogels, offering insights for material science researchers.

3.
Biophys Chem ; 309: 107229, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38555653

ABSTRACT

The study specifically investigates the solubilities of L-isoleucine and L-tyrosine in water-mixed solvent systems (DMF, DMSO, and ACN), exploring the behaviour of amino acids in complex environments. The experimental methods prioritize meticulous solvent purification to ensure reliable results. The work explores solubility data, uncovering temperature-dependent trends and intricate interactions influencing solubility in the chosen mixed solvent systems. The study emphasizes the impact of thermodynamic properties, solvent-solvent interactions, and amino acid structure on solubility patterns. The broader implications highlight the relevance of understanding amino acid behaviour in diverse solvent environments, offering potential applications in cosmetics and pharmaceutical industries. The distinct solubility patterns contribute valuable insights, enhancing on the understanding of the solution stability and interactions of L-isoleucine and L-tyrosine in different solvent systems. In conclusion, work suggests the enhanced utilization of L-isoleucine and L-tyrosine in various industries, driven by a profound understanding of their solubility in mixed solvent systems. The research expands our knowledge of amino acid behaviour, paving the way for advancements in industries relying on protein-based products and technologies.


Subject(s)
Amino Acids , Isoleucine , Solvents/chemistry , Solubility , Tyrosine , Thermodynamics , Water/chemistry
4.
Biophys Chem ; 307: 107195, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38325036

ABSTRACT

This paper delves into an investigation of the solubility characteristics of L-tryptophan within binary solvent systems containing aqueous acetonitrile. The primary emphasis of the study revolves around assessments based on mole fractions. The study utilizes these solubility values to assess thermodynamic constraints, including solution entropies and solution transfer free energetics. The calculated thermodynamic energies are correlated with interaction parameters, including Gibbs free energies and entropies, pertaining to the transfer of L-tryptophanfrom water to binary solvent blends of acetonitrile and water. Mathematical expressions are utilized to determine the transfer Gibbs free energies for chemical interactions, and the consequent entropies are clarified within the framework of solvent-solvent interactions. To expound upon the stability of L-tryptophan within the water-acetonitrile mixed system, we investigate the energetic aspects related to the transfer of chemicals Gibbs free energies. Additionally, standard temperature (298.15 K) is employed to calculate various related physicochemical parameters of solute/solvent.


Subject(s)
Tryptophan , Water , Temperature , Solubility , Thermodynamics , Solvents
5.
Biophys Chem ; 306: 107154, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38142475

ABSTRACT

This research provides a thorough investigation into the solubility behavior and solution thermodynamics of l-threonine in significant organic solvent systems. The work was done on measuring the actual solubility and subsequently calculating overall transfer solvation free energetics (∆Genergetic0i) and transfer entropies (∆St0i) at a temperature of 298.15 K. These measurements were performed as l-threonine transitioned from water to different water-organic mixed solvents systems. The saturated solubilities of l-threonine were determined using the 'gravimetric method' at five equidistant temperatures namely 288.15 K, 293.15 K, 298.15 K, 303.15 K and 308.15 K. By analyzing the data on solubility, we further obtained the different energies involved in solvation related issues. In the case of single solvents, the nature of solubility of l-threonine was observed like: dimethylsulfoxide (DMSO) < acetonitrile (ACN) < N, N-dimethylformamide (DMF) < ethylene glycol (EG) < water (H2O), irrespective of the experimental conditions. Specifically, at 298.15 K, the solubilities of l-threonine in single solvents were found to be as follows: 0.8220 mol per kg of water, 0.3101 mol per kg of EG, 0.1337 mol per kg of DMF, 0.1107 mol per kg DMSO and 0.1188 mol per kg of ACN. This research critically examines the relationship between the experimental saturated solubility of l-threonine and the complex properties influencing its solvation energy in diverse aqueous organic solvent systems.


Subject(s)
Dimethyl Sulfoxide , Water , Temperature , Solubility , Solvents , Thermodynamics
6.
Nanoscale Adv ; 5(23): 6714-6723, 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-38024309

ABSTRACT

A novel method has been successfully developed for creating supramolecular metallogels using zinc(ii) ions and 5-aminoisophthalic acid as the gelator (low molecular weight gelator) in a dimethylformamide (DMF) solvent at room temperature. Comprehensive rheological investigations confirm the robust mechanical strength of the resulting zinc(ii)-metallogel. Microstructural analysis conducted through field-emission scanning electron microscopy (FESEM) unveils a unique flake-like morphology, with energy-dispersive X-ray (EDX) elemental mapping confirming the prevalence of zinc as the primary constituent of the metallogel. To understand the formation mechanism of this metallogel, Fourier-transform infrared (FT-IR) spectroscopy was employed. Notably, these supramolecular zinc(ii)-metallogel assemblies exhibit electrical conductivity reminiscent of metal-semiconductor (MS) junction electronic components. Surprisingly, the metallogel-based thin film device showcases an impressive electrical conductivity of 1.34 × 10-5 S m-1. The semiconductor characteristics of the synthesized zinc(ii)-metallogel devices, including their Schottky barrier diode properties, have been extensively investigated. This multifaceted study opens up a promising avenue for designing functional materials tailored for electronic applications. It harnesses the synergistic properties of supramolecular metallogels and highlights their significant potential in the development of semiconductor devices. This work represents a novel approach to the creation of advanced materials with unique electronic properties, offering exciting prospects for future innovations in electronic and semiconductor technologies.

7.
Indian J Community Med ; 48(1): 31-40, 2023.
Article in English | MEDLINE | ID: mdl-37082381

ABSTRACT

Oxygen support became one of the rate-limiting steps for medical care during COVID-19 pandemic in India. The primary aim of this study was to appraise the manufacturing, supply, and distribution of medical oxygen during the pandemic. The secondary objectives were to highlight the coordination of various stakeholders to mitigate the oxygen surge and to present a critical analysis of India's response to the emergent situation. Using an analytic approach, we have delineated India's response to mitigate the medical oxygen surge during the distressing second peak between March-May 2021. In the pre-COVID-19 era, of the total 6900 MT of oxygen produced in India, only 1000 MT was available for medical usage, which was increased up to 19940 MT through the strengthening of in-house oxygen manufacturing, low-cost innovations, and enhanced storage facilities. High-burden states were identified, and transport was facilitated through departments of railways, defence and civil aviation. Real-time scrutiny of the oxygen supply was provided. Essential customs duties on importing oxygen and vital equipment were exempted, along with other swift decisions. National Oxygen Stewardship Program' was initiated to build the capacity of health care workers in oxygen therapy and rational use of surplus oxygen. The pandemic overwhelmed the health system. But a coordinated multi-stakeholder approach facilitated the fight against oxygen surge. However, a comprehensive pandemic response will need more than just oxygen. This resourceful utilization offers a silver lining and facilitates the improvement of health systems and health outcomes in the long term.

8.
ACS Omega ; 7(1): 1428-1436, 2022 Jan 11.
Article in English | MEDLINE | ID: mdl-35036804

ABSTRACT

A Co(III) complex of 1-amino-4-hydroxy-9,10-anthraquinone (QH) (Scheme-1) having the molecular formula CoQ3 (Scheme-2) was prepared and characterized by elemental analysis, FTIR spectroscopy, UV-vis spectroscopy, fluorescence spectroscopy, and mass spectrometry. In the absence of a single crystal, the energy-optimized molecular structure of CoQ3 was determined by employing computational methods that was validated using spectroscopic evidences, elemental analysis, and mass spectrometry data. The electrochemical properties of the complex were analyzed using cyclic voltammetry and indicate a substantial modification of the electrochemical properties of the parent amino-hydroxy-9,10-anthraquinone. CoQ3 was thereafter tested on MCF-7 human breast cancer cells. The IC50 value for a 24 h incubation was found to be (95 ± 0.05) µg/mL. The study showed that such cancer cells underwent both early and late apoptosis following the interaction with CoQ3.

9.
Heliyon ; 5(8): e02304, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31485517

ABSTRACT

In this study we estimated the solubilities of glycine, D,L-alanine, D,L-nor-valine and D,L-serine in aqueous mixtures of potassium sulfate (K2SO4) at 298.15 K using analytical 'gravimetric method'. The experimental solubilities of homologous series of amino acids in aqueous K2SO4 mixture were discussed in terms of relative solubility, salting-in and salting-out effect by evaluating the influential constants. The effect of physicochemical and chemical factors on solubility were discussed briefly and correlated with the thermodynamics. Initially, the study of solvation energetics such as transfer Gibbs energies were evaluated based on the calculations from solubility data and relative stability of the experimental molecules was discussed under the experimental condition.

10.
Nanomicro Lett ; 11(1): 103, 2019 Nov 22.
Article in English | MEDLINE | ID: mdl-34138052

ABSTRACT

Sunlight is the most abundant renewable energy resource, providing the earth with enough power that is capable of taking care of all of humanity's desires-a hundred times over. However, as it is at times diffuse and intermittent, it raises issues concerning how best to reap this energy and store it for times when the Sun is not shining. With increasing population in the world and modern economic development, there will be an additional increase in energy demand. Devices that use daylight to separate water into individual chemical elements may well be the answer to this issue, as water splitting produces an ideal fuel. If such devices that generate fuel were to become widely adopted, they must be low in cost, both for supplying and operation. Therefore, it is essential to research for cheap technologies for water ripping. This review summarizes the progress made toward such development, the open challenges existing, and the approaches undertaken to generate carbon-free energy through water splitting.

11.
Dalton Trans ; 44(12): 5428-40, 2015 Mar 28.
Article in English | MEDLINE | ID: mdl-25691434

ABSTRACT

A 1 : 2 copper(II) complex of 1-amino-4-hydroxy-9,10-anthraquinone (QH) having the molecular formula CuQ2 was prepared and characterized by elemental analysis, NMR, FTIR, UV-vis and mass spectroscopy. The powder diffraction of the solid complex, magnetic susceptibility and ESR spectra were also recorded. The presence of the planar anthraquinone moiety in the complex makes it extremely difficult to obtain a single crystal suitable for X-ray diffraction studies. To overcome this problem, density functional theory (DFT) was used to evaluate an optimized structure of CuQ2. In the optimized structure, it was found that there is a tilt of the two planar aromatic anthraquinone rings of the complex with respect to each other in the two planes containing the O-Cu(II)-O plane. The present study is an important addition to the understanding of the structural aspects of metal-anthracyclines because there are only a few reports on the actual structures of metal-anthracyclines. The theoretical vibrational spectrum of the complex was assigned with the help of vibrational energy distribution analysis (VEDA) using potential energy distribution (PED) and compared with experimental results. Being important in producing the biochemical action of this class of molecules, the electrochemical behavior of the complex was studied in aqueous and non-aqueous solvents to find certain electrochemical parameters. In aqueous media, reduction involves a kinetic effect during electron transfer at an electrode surface, which was characterized very carefully using cyclic voltammetry. Electrochemical studies showed a significant modification in the electrochemical properties of 1-amino-4-hydroxy-9,10-anthraquinone (QH) when bound to Cu(II) in the complex compared to those observed for free QH. This suggests that the copper complex might be a good choice as a biologically active molecule, which was reflected in the lack of stimulated superoxide generation by the complex.


Subject(s)
Anthraquinones/chemistry , Coordination Complexes/chemistry , Copper/chemistry , NADH Dehydrogenase/metabolism , Superoxides/metabolism , Amination , Anthraquinones/pharmacology , Coordination Complexes/pharmacology , Copper/pharmacology , Humans , Models, Molecular , Spectrum Analysis , X-Ray Diffraction
12.
Biochem Biophys Rep ; 4: 312-323, 2015 Dec.
Article in English | MEDLINE | ID: mdl-29124219

ABSTRACT

The X-ray diffraction and spectroscopic properties of 1-amino-4-hydroxy-9,10-anthraquinone (1-AHAQ), a simple analogue of anthracycline chemotherapeutic drugs were studied by adopting experimental and computational methods. The optimized geometrical parameters obtained from computational methods were compared with the results of X-ray diffraction analysis and the two were found to be in reasonably good agreement. X-ray diffraction study, Density Functional Theory (DFT) and natural bond orbital (NBO) analysis indicated two types of hydrogen bonds in the molecule. The IR spectra of 1-AHAQ were studied by Vibrational Energy Distribution Analysis (VEDA) using potential energy distribution (PED) analysis. The electronic spectra were studied by TDDFT computation and compared with the experimental results. Experimental and theoretical results corroborated each other to a fair extent. To understand the biological efficacy of 1-AHAQ, it was allowed to interact with calf thymus DNA and human breast adino-carcinoma cell MDA-MB-231. It was found that the molecule induces apoptosis in this adinocarcinoma cell, with little, if any, cytotoxic effect in HBL-100 normal breast epithelial cell.

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