Heavy metals such as Hg2+, Pb2+, and Cd2+ are among the most hazardous environmental pollutants due to their high toxicity and tendency to bioaccumulate in living organisms. Mercury, particularly in the form of alkylated mercury, poses a serious public health concern owing to its accumulation in fish and other aquatic life, which subsequently enters the human food chain. There are different fish species across Asia, such as Catla, Rui, Aar, Bhetki, and Tilapia, that have been reported to bioaccumulate these toxic metals in their tissues. In this study, we present a green-synthesized nanohybrid, C-Ag NPs@rGO, as an efficient sensing platform for the detection of Hg2+ ions and the detection of mercury in fish serum samples. The nanocomposite's high surface area and abundant active sites facilitate enhanced interactions with target analytes, making it highly effective for sensing applications. Although numerous Hg2+ sensors have been reported, many still face challenges related to insufficient sensitivity and relatively high detection limits. In contrast, our C-Ag NPs@rGO sensor demonstrates excellent selectivity, pH-dependent fluorescence sensing capabilities, and excellent electrochemical sensing ability. Notably, under near-physiological pH conditions, the sensor achieved a remarkably low limit of detection (LOD) of 6.64 × 10-3 nM, 34.2 × 10-3 nM for Hg2+ through fluorescence measurement, and an LOD value of 0.032 nM through cyclic voltammetry measurement, substantially lower than most of the reported values. This eco-friendly sensing platform offers a promising approach for the detection of trace levels of mercury in both biological and environmental samples.

The present research study is centered around the synthesis, characterization, and biological application of a ternary mixed-ligand based binuclear Cu(II) complex [Cu2(trans-1,4-chdc)(4,4 '-Me2-2,2 '-bpy)2(5,5 '-Me2-2,2 '- bpy)2]center dot 2(cis-H21,4-chdc)center dot 2(BF4-) (1) by meticulous incorporation of 4,4 '-dimethyl-2,2 '-bipyridine (4,4 '-Me2-2,2 '- bpy), 5,5 '-dimethyl-2,2 '-bipyridine (5,5 '-Me2-2,2 '-bpy) and cis- and trans- mixture of 1,4-cyclohexanedicarboxylic acid (H21,4-chdc). Hirshfeld analysis is employed to validate non-bonded interactions, demonstrating the existence of widespread pi center dot center dot center dot pi stacking interactions between adjacent 4,4 '-Me2-2,2 '-bpy ligands at a distance of 3.757 angstrom, forming a one-dimensional (1D) supramolecular polymer chain. The biological activity of complex 1 is explored via docking study, driven by the inherent biological inclination of the Cu(II) complexes. Agreeably, the coordination complex 1 displays a favorable binding to DNA, specifically binds to the major groove of DNA and the aromatic pyridine ring of the ligand partially intercalates into the base pairs with a binding constant (Kb) of 1.98 x 105 M- 1 .

Lawsone (2-hydroxy-1,4-naphthoquinone), also known as hennotannic acid, is a red-orange dye present in the leaves of the henna plant (Lawsonia inermis) having lots of biological activities. In this paper, we have investigated the structural basis of binding affinities of Lawsone towards two different targets namely, calf thymus DNA (CT-DNA) and protein bovine serum albumin (BSA) using experimental and computational approaches. This phytochemical binds to the minor groove of DNA and Sudlow site II, Domain III of BSA. The binding constants obtained from spectroscopic studies for Lawsone with DNA and BSA have been determined as 1.79 × 10³ M-1 and 2.18 × 10³ M-1, respectively with corresponding Gibbs free energies of -4.46 kcal/mol and -4.58 kcal/mol. Conformational changes in the secondary structures of the receptors upon binding with Lawsone is observed. Isothermal titration calorimetry (ITC) experiments reveal that binding is favoured mainly due to negative enthalpy changes (-18.2 kcal/mol for DNA and -98.77 kcal/mol for BSA). Molecular docking and dynamics simulations elucidate intermolecular contacts between Lawsone and the receptors, providing insight into the energetic profile of the complexes and revealing Lawsone's reorientation within the binding sites. Both experimental and computational findings highlight the significance of hydrogen bonding and hydrophobic interactions in the binding process, offering valuable insights into Lawsone's molecular interactions with biomolecules and its potential therapeutic applications.

Two new coordination complexes were synthesized, which are formulated as [Cu-2(cis-1,4-chdc)(4,4' -Me(2)bpy)(4)] & sdot; 2(ClO4-) & sdot; H2O (1) and [Cu-2(cis-1,4-chdc)(5,5' -Me(2)bpy)(4)] & sdot; 2(ClO4-) & sdot; H2O (2), using cis-1,4-cyclohexanedicarboxylic acid (cis-1,4-H(2)chdc), 4,4 '-dimethyl-2,2 '-bipyridine (4,4' -Me(2)bpy), 5,5' -dimethyl-2,2' -bipyridine (5,5' -Me2bpy). Interestingly, cis-1,4-chdc adopts chair form in 1 and boat conformation in 2. This conformational change impacts the DNA binding capacities of the complexes as revealed by spectrophotometry, circular dichroism (CD) spectroscopy and docking studies. The complex 1 having the chair conformation shows higher affinity towards the DNA base pairs due to anti-alignment of the planar aromatic pyridyl rings of 4,4' -Me(2)bpy, which strongly intercalates with the adenosine base pairs of DNA by formation of three pi-pi stacking and two extra pi-positive stacking interactions between adenosine bases and positively charged nitrogen. Conversely, 5,5 '-Me2bpy with planar aromatic pyridyl rings of complex 2 shows bis-intercalation with weak affinities toward base pairs by formation of two pi-pi stacking and one pi-positive stacking interactions.

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Environmental pollution poses a major problem now a day. Several dyes, in the form of industrial waste, pollute water body and may cause adverse effects to human health. In this paper ADME and toxicity of fives Phenothiazinium group of dyes Methylene blue (MB), Azure A (AA), Azure B (AB), Azure C (AC) and Toluidine Blue O (TBO) were predicted using Swiss ADME and Protox II tools. Results showed these dyes may herm for living organism due to their carcinogenic, mutagenic and hepatotoxic properties. Removal efficiency of these dyes using okra plant product were determined using spectroscopic, thermodynamic and molecular modeling study. It was revealed that these dyes adsorb on the surface of okra leaf mostly at pH 7.0 and the adsorption isotherms were found to fit in Langmuir and Freundlich isotherm model, while Temkin model fails to do this. Mucilage present in different parts of okra plant plays a significant role on removal of these dyes and is able to remove near about 71-92 % of dyes from water body by itself. As this process did not fit in any of above said adsorption isotherm model, it may be suggested that some other mechanism may happen. Further studies explore that these dyes bound to the hydrophobic pocket of mucilage with binding affinity in the order of 105 M- 1 and the bindings were exothermic in nature with enthalpy change in the range of - 2.94 to - 4.28 kcal/mole. Molecular docking study validate all the experimental results obtained from spectroscopic and thermodynamic study and enlighten the role of structure of dyes on their binding affinity to mucilage. This paper will help to systematically understand the role of okra plant products on removal efficiency of Phenothiazinium group of dyes with their structural variations.

This paper studies the two-dimensional unsteady incompressible Ag-water and CuO-water nanofluid flow in a semi-porous expanding-contracting channel in the presence of thermal radiation effect. The continuity equation, Navier-Stokes equation, and energy equation governing the model are transformed into a set of non-dimensional ordinary differential equations using appropriate transformations. These dimensionless governing equations are solved using power series with the aid of the Hermite-Padé approximation method. The influences of physical parameters such as Reynolds number, expansion ratio, solid volume fraction, Prandtl number, Magnetic parameter, and shape factor are depicted in velocity and temperature profiles. Moreover, the average Nusselt number and skin friction coefficient are also investigated with the effect of Reynolds number, solid volume fraction, and expansion ratio. It is observed that the heat transfer rate decreases significantly as the shape factor increases.

Recent focus has been directed toward semiconductor nanocrystals owing to their unique physicochemical properties. Nevertheless, the synthesis and characterization of quantum dots (QDs) pose considerable challenges, limiting our understanding of their interactions within a biological environment. This research offers valuable insights into the environmentally friendly production of silver quantum dots (Ag QDs) using lentil extract and clarifies their distinct physicochemical characteristics, previously unexplored to our knowledge. These findings pave the path for potential practical applications. The investigation of the phytochemical-assisted Ag QDs' affinity for BSA demonstrated modest interactions, as shown by the enthalpy and entropy changes as well as the associated Gibbs free energy during their association. Steady-state and time-resolved fluorescence spectroscopy further demonstrated a transient effect involving dynamic quenching, predominantly driven by Forster resonance energy transfer. Additionally, the study highlights the potential broad-spectrum antibacterial activity of Ag QDs (<5 nm, a zeta potential of -3.04 mV), exhibiting a remarkable MIC value of 1 mu g/mL against Gram-negative bacteria (E. coli) and 1.65 mu g/mL against Gram-positive bacteria (S. aureus). They can readily enter cells and tissues due to their minuscule size and the right chemical environment. They cause intracellular pathway disruption, which leads to cell death. This outcome emphasizes the distinctive biocompatibility of the green-synthesized Ag QDs, which has been confirmed by their MTT assay-based cytotoxicity against the PC-3 and Wi-38 cell lines.

DNA double-strand breaks (DSBs) are considered one of the most harmful forms of DNA damage. These DSBs are repaired through non-homologous end joining (NHEJ) and homologous recombination (HR) pathways and defects in these processes can lead to genomic instability and promote tumorigenesis. Phosphatase and Tensin homolog (PTEN) are crucial in HR repair. However, its involvement in the NHEJ repair pathway has remained elusive. In this study, we investigate the function of epigenetic regulation of PTEN in the NHEJ repair pathway. Our findings indicate that both the phosphorylation and phosphatase activity of PTEN are required for efficient NHEJ-mediated DSB repair. During the DNA damage response, we observed a reduced expression and chromatin attachment of the key NHEJ proteins, including Ku70/80, DNA-PKcs, XRCC4, and XLF, in PTEN-null cells. This reduction was attributed to the instability of these NHEJ proteins, as confirmed by our protein half-life assay. We have demonstrated that the DNA-PKcs inhibitor, NU7026, suppresses the DNA damage-induced phosphorylation of the C-terminal of PTEN. Thus, our study indicates that PTEN could be a target of DNA-PKcs. Protein-protein docking analysis also shows that PTEN interacts with the C-terminal region of DNA-PKcs. PTEN null cells exhibit compromised DNA-PKcs foci after DNA damage as it is in a hyper-phosphorylated state. Phospho-PTEN assists in recruiting DNA-PKcs on the DNA damage site by maintaining its hypo-phosphorylated state which also depends on its phosphatase activity. Therefore, after DNA damage, crosstalk between PTEN and DNA-PKcs modulates the NHEJ pathway. Thus, during DNA damage, PTEN gets phosphorylated directly or indirectly by DNA-PKcs and attaches to chromatin, resulting in the dephosphorylation of DNA-PKcs and subsequently recruitment of other NHEJ factors on chromatin occurs for efficient execution of the NHEJ pathway. Thus, our research provides a molecular understanding of the epigenetic regulation of PTEN and its significant role in controlling the NHEJ pathway.

In this work, we have established a simple, efficient, non-toxic, cost-effective and completely green strategy to synthesize carbon dots (CDs) using Mucuna pruriens (alkushi) seeds. Synthesized CDs through facile one-pot hydrothermal route has a spherical shape with an average diameter of 4.02 nm. Surface analysis of these CDs was performed utilizing XPS, FTIR, and zeta potential measurement, confirming the presence of -OH, -NH2, and -COOH groups. The obtained CDs exhibit excellent photostability, high quantum yield and possess outstanding water solubility. Moreover, these CDs provide high response for detection of Au3+ ions through fluorescence quenching with a noticeable change in colour of the solution (colorimetric). The LOD was calculated to be 51.20 nM using 3 sigma/k rule. The mechanism of sensing was established through FTIR, florescence lifetime, UV and Isothermal Titration Calorimetry (ITC). These experiments indicate that a ground state complex formed between CDs and Au3+ ions and subsequent reduction to Au-0. The specificity towards Au3+ ions was tested against different interfering ions and was implemented to analysis the real sample. The synthesized CDs have also the potential to be applied in temperature sensing application. The cytotoxicity and biocompatibility were evaluated against prostate cancer cell line (PC3 cell) and a human lung fibroblast cell line (WI38 cell). Finally, Non-cytotoxic CDs were applied for live cell imaging and in vitro sensing of Au3+ ions.

A Co(II) compound [Co2(ip)2(4-phpy)4 center dot(H2O)2] (1); (H2ip = isophthalic acid and 4-phpy = 4-phenylpyridine) has been synthesized employing slow diffusion technique. Single crystal X-ray analysis reveals that compound 1 crystallizes in the triclinic system, space group P 1 with a = 10.7041(3) angstrom, b =14.2959(4) angstrom, c =18.3474(5) angstrom; alpha = 73.3930(10)degrees, beta = 76.0190(10)degrees, gamma = 88.4780(10)degrees with V = 2608.06(13) angstrom 3. The compound 1 forms based one-dimensional coordination polymer (1D CP) constructed by distorted octahedral Co(II) centres, which are interconnected via strands of isophthalate bridges resulting in a 1D chain polymer. The pyridine-based ligands are decorated as arms on both sides of Co(II) centers. The unique coordinating characteristics of isophthalate and pyridine ligands are accounted for the strong affinity towards DNA molecules for compound 1. The binding affinities of compound 1 with DNA have been investigated via docking studies. Hirshfeld surface analysis was performed in order to check out the nature of intermolecular interactions and packing modes of compound 1 in the crystalline state.

A Cu(II) compound [Cu2(5-nip)2(3-brpy)2 & sdot;(H2O)2 & sdot;(DMF)2] (1) was synthesized using 5-nitroisophthalic acid (H25-nip) and 3-bromopyridine (3-brpy) employing slow diffusion technique. Visibly distinct blue-colored crystals of compound 1 were obtained. Single crystal X-ray analysis discloses that compound 1 crystallizes in the triclinic system, having space group P1 with cell dimensions a = 12.4491(14) angstrom, b = 13.6238(15) angstrom, c = 14.3315(15) angstrom; alpha = 68.027(3)degrees, beta = 69.914(3)degrees, gamma = 87.173(3)degrees and V = 2108.3(4)angstrom 3. The compound contains core metal atom Cu(II) that is hexa-coordinated to 5-nip, 3-brpy, dimethylformamide (DMF), and aqua molecule resulting in one- dimensional coordination polymer (1D CP), propagated via strands of 5-nip bridges. The pyridine-based ligand and aqua ligands are decorated as arms on both sides of Cu(II) centers. The prominence of hydrogen bonding interactions in compound 1 was found which leads to the formation of 1D double-chain strand. The combination of 5-nip and 3-brpy ligands is responsible for the strong affinity towards DNA molecules for compound 1. Docking studies have been employed to examine DNA binding affinity. Hirshfeld surface analysis was carried out in order to check out the nature of intermolecular interactions and packing modes of compound 1 in the crystalline state.

Two phytochemicals, thymol and thymoquinone obtained from thymes (Thymus vulgaris L., Lamiaceae etc.) and Nagila Sativa seed, respectively. Both the phytochemicals show several biochemical activities like anticancer, antimicrobial etc. In this paper, we studied the affinities of thymol and thymoquinone towards calf thymus DNA (CT-DNA) and protein (bovine serum albumin). Spectroscopic and molecular modelling studies revealed that both compounds have a high affinity toward both the receptors; DNA and protein. Both phytochemicals binds to the minor grooves of DNA and suitable pockets of protein. Several free energy function and hydrogen bonding play significant role during the binding phenomenon.Communicated by Ramaswamy H. Sarma

Cancer has been regarded as one of the leading causes of mortality and has distressed people globally. There are many conventional treatments like chemotherapy, radiotherapy, surgery, hormone therapy etc. But these treatments have many harmful side effects, which have restricted conventional treatments efficacy. Many phytochemicals found in various plants have been studied largely for their anticancer properties. Many phytochemicals present in ayurvedic and homeopathic medicines have also been determined as good anticancer drugs. Hence, there are lots of opportunities for researchers to develop potent anticancer drugs from medicinal plants available in several countries. Researchers also need to acquire knowledge on the action of phytochemicals to develop more potent anticancer drugs. The present review discussed systematically the anticancer activities of different class of phytochemical compounds.

Investigation of one pendant acetate bearing a mononuclear Ni( ii ) complex (1) and bridging acetate bearing a dinuclear Cu( ii ) complex (2) with respect to their DNA/HSA binding efficacy along with their apoptotic induced anticancer properties.

Two binuclear copper (II) complexes ([Cu2(L1)2(Py)4] (1) and [Cu2(L2)2(Py)4] (2) where H2L1 (3-((2-hydroxybenzylidene)amino)benzoic acid and H2L2 (3-((2-hydroxy-5-nitrobenzylidene)amino)benzoic acid) have been synthesized and characterized by analytical and different spectroscopic technique. The X-ray diffraction analysis of both 1 and 2 complexes revealed that the geometry around the copper (II) centres are distorted square pyramidal. The crystal lattice in both 1 and 2 are stabilized by several types of intermolecular hydrogen bonds and & pi;...& pi; interactions. The intermolecular interactions on the crystal packing of 1 and 2 have been further studied by Hirshfeld surface analysis and corresponding 2D fingerprint plots. The interaction of 1 and 2 with calf thymus DNA (ct-DNA) have also been evaluated using absorption and fluorescence techniques and the result indicates that both 1 and 2 can bind to ct-DNA via an intercalative mode. The binding constant using absorption spectra between 1 with ct-DNA and 2 with ct-DNA have been found to be (10.3 & PLUSMN; 0.02) x 104 M-1 and (6.91 & PLUSMN; 0.01) x 104 M-1 respectively. Molecular docking studies also support the partial insertion of both 1 and 2 into the DNA backbone. Importantly, in Cu(II) complex 2, the Schiff base ligand possessing a significant electron withdrawing -NO2 group exhibits less interaction with ct-DNA compared to 1, containing less or no electron withdrawing character Schiff base.

A new quercetin-based iron(III) cationic complex [Fe(Qr)-Cl(H2O)(MeO)] (complex 1) is created in the current study by condensation of quercetin with ferric chloride in the presence of Et3N. Comprehensive spectroscopic analysis and conductometric measurement are used to pinpoint complex 1. The generated complex's +3-oxidation state has been verified by electron paramagnetic resonance (EPR) research. Density functional theory analysis was used to structurally optimize the structure of complex 1. Before biomedical use, a variety of biophysical studies are implemented to evaluate the binding capacity of complex 1 with DNA and human serum albumin (HSA) protein. The findings of the electronic titration between complex 1 and DNA, as well as the stunning fall in the fluorescence intensities of the HSA and EtBr-DNA/DAPI-DNA domain after complex 1 is gradually added, give us confidence that complex 1 has a strong affinity for both macromolecules. It is interesting to note that the displacement experiment confirms partial intercalation as well as the groove binding mechanism of the title complex with DNA. The time dependent fluorescence analysis indicates that after interaction with complex 1, HSA will exhibit static quenching. The thermodynamic parameter values in the HSA-complex 1 interaction provide evidence for the hydrophobicity-induced pathway leading to spontaneous protein-complex 1 interaction. The two macromolecules' configurations are verified to be preserved when they are associated with complex 1, and this is done via circular dichroism spectral titration. The molecular docking investigation, which is a theoretical experiment, provides complete support for the experimental findings. The potential of the investigated complex to be an anticancer drug has been examined by employing the MTT assay technique, which is carried out on HeLa cancer cell lines and HEK-293 normal cell lines. The MTT assay results validate the ability of complex 1 to display significant anticancer properties. Finally, by using the AO/PI staining approach, the apoptotic-induced cell-killing mechanism as well as the detection of cell morphological changes has been confirmed.

Here, a simple, one step, lucrative and green synthesis of Cassia fistula leaf extract inspired antibacterial silver nanoparticles (CF-SNPs) was provided. Characterization of these CF-SNPs were achieved by using various spectroscopic techniques for instance Ultraviolet Visible (UV-Vis) Spectroscopy, Fourier-Transform Infrared (FTIR) Spectroscopy, Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray (EDX). The effective antibacterial action of the CF-SNPs was checked against Escherichia coli (E. Coli) DH5-Alpha where MIC was 1.6 nM. Anticancer dynamism of the CF-SNPs was also tested in opposition to skin melanoma, A375 cell lines in which 4.4 nM was IC50. The binding proneness of HSA towards CF-SNPs was investigated by means of UV-Vis Spectroscopy, Fluorescence Spectroscopy, Time Resolved Fluorescence Spectroscopy, Circular Dichroism (CD) Spectroscopy, Dynamic Light Scattering, and Isothermal Titration Colorimetry (ITC). CD spectroscopy established minor secondary structural exchange of HSA in HSA-CF-SNPs complex. ITC and Time Resolved Fluorescence Spectroscopy verified the static type quenching mechanism involved in HSA-CF-SNPs complex. The binding constant was 3.45 × 108 M-1 at 298.15K from ITC study. The thermodynamic parameters showed that the interaction was occurred spontaneously by the hydrophilic forces and hydrogen bonding.Communicated by Ramaswamy H. Sarma.

A new muconate based Cu(II) metal complex [Cu2(muco)(5,5'-Me2bpy)4]·4ClO4¯ (1; H2muco = trans, trans-1,3-butadiene-1,4-dicarboxylic acid or trans, trans-muconic acid and 5,5'-Me2bpy = 5,5'-dimethyl-2,2'-bipyridine) has been synthesized and structurally characterized. X-ray structure analysis reveals that 1 forms a binuclear complex with five coordinated square pyramidal geometry of central Cu(II) ion attached to two bipyridine and a muco ligands. Docking studies has been carried out which reveals the successful binding of metal complex to the major groove of DNA and the planner aromatic bipyridyl ligand partially intercalates into the base pairs. The synthesized complex fits into the pocket of bovine serum albumin (BSA), while maximum fraction submerges into BSA binding pocket. An extra coordinate bond has been found forming through the oxygen of 158 asparagines amino acid which subsequently forms a new six coordinated octahedral complex. Experimental studies have been performed to validate all the data obtained from the docking studies. This study reveals highly diverse affinity and binding mode of synthesized complex towards DNA and protein. Therefore, the synthesized complex may pave the way to be used as a specific protein binder (low affinity to DNA or RNA) bioactive compound.