Lady Brabourne College

This study aims to assess the effects of salinity on the growth and survival of freshwater catfish Mystus gulio and to analyse the biochemical and hormonal alterations. The fish were exposed to increasing salt concentrations of upto 22.27 PSU in experimental tanks within a study period of 21 days with an aim to investigate into the effect of salinity stress on the total protein profile and, synthesis of the stress hormone cortisol and stress protein HSP70 as well as the sex steroid hormones estradiol and testosterone. This euryhaline fish showed tolerance with different salinities upto approximately 9 PSU beyond which, most fishes succumbed to higher salinities. 50% of mortality was noticed at salt concentrations between 8.14-8.19 PSU. There was a gradual decrease in the protein concentration with increasing salt concentrations. SDS-PAGE revealed the disappearance of a 91.5 kDa, 77.8 kDa and an 18.2 kDa protein band and the appearance of a 60.7 kDa, 21.4 kDa and a 15.5 kDa protein band at higher salt concentrations. The Cortisol and HSP70 concentration showed a gradual increase in muscle tissue with increasing salinities but in case of gills there was a gradual decline after an initial sharp rise. Low salinity stress upregulated estradiol synthesis but level of testosterone showed a decrease with increasing salt concentrations.

An eco-friendly and cost-effective ligand-free protocol has been developed for the direct hydroxylation of aryl halides in aqueous medium using easily accessible Al2O3-supported Ni nanoparticles as a stable heterogeneous catalyst in the presence of a strong base KOH (potassium hydroxide), where the aliphatic halides remained unaffected. A wide variety of aryl halides, such as iodides, bromides, and chlorides, were successfully hydroxylated and converted into their corresponding phenols with yields ranging from 80 % to 91 %. The crystalline nature of the synthesized nanocatalyst has been analysed by powder X-ray diffraction, which exhibited that the synthesized nanocatalyst consists of metallic Ni supported by Al2O3. The high-resolution XPS spectra of the Ni 2p region demonstrate the predominant presence of metallic nickel (Ni0) on the surface of the synthesized nanocatalysts. The TEM and SEM images distinctly showcased the crystalline nature of the synthesized nanocatalyst, revealing a well-defined architecture. Moreover, the catalyst was recyclable for up to 5 catalytic runs without reducing their catalytic performance. We have also performed the density functional theory to gain insights into the role of the Ni@Al2O3 hybrid catalyst in the hydroxylation reaction of haloarenes.

Accurate and selective recognition of ions and molecules is crucial in medical and diagnostic research. Cu(II)- and Zn(II)-based coordination polymers (CPs) have been designed in this work to detect trace levels of melatonin and tryptophan and evaluate their anticancer activity. The [Cu2(4-bph)2(adc)4]n (CP1) (4-bph = (1E,2E)-1,2-bis(pyridin-4-ylmethylene) hydrazine; Hadc = 1-adamantanecarboxylic acid) structure shows that 4-bph serves as a bridging pyridyl-N ligand and adc- is a chelating and binuclear bridging ligand, forming an eight-membered Cu(μ-COO)2Cu motif. In Zn(II)-CP, 4-bph is a bridging ligand, while adc- is monodentate, yielding [Zn(4-bph)(adc)2]n (CP2). In CP1, π-π stacking (∼3.875 Å) and hydrogen bonding generate a 3D supramolecular network while CP2 forms pyridyl-N bridging zigzag 1D CP. The BET analysis measures higher pore volume of CP1 (0.06 cm3 g-1) than CP2 (0.018 cm3 g-1). The CP1 is weakly emissive, and upon irradiation at 312 nm, it emits at 392 nm which has been enhanced by the addition of tryptophan (Trp) (LOD, 44.65 nM), in the presence of 19 other amino acids. The CP1 senses melatonin (MEL) (LOD, 38 nM) also in the presence of various proteins, enzymes, and neuroactive metal ions. Blood serum is used for the measurement of melatonin in blood serum (pH 7.4) and also tryptophan measurement in milk. The CP2 is inactive toward sensing performance. DFT computation using crystallographic parameters reveals a stronger binding of CP1 with Trp (-221 kcal mol-1) than that of CP2 (-38.22 kcal mol-1). Anticancer assays show that CP1 is more potent than CP2 against MCF-7 breast cancer cells, IC50 values are 196.8 ± 2.31 nM (CP1) and 258.2 ± 2.08 nM (CP2). Both CPs exhibit minimal toxicity toward normal PBMCs at these doses. Theoretical evaluation has also been used to explain the luminescence and selective sensing behavior to Trp and MEL.

Graphitic carbon nitride (g-C₃N₄) based materials have shown great potential for biomedical applications, including combination therapy, imaging, bioconjugation, and drug delivery due to their excellent biocompatibility, flexible surface modification, and tunable band-gap structure. These systems are widely employed for light driven water splitting and the generation of reactive oxygen species (ROS) for photodynamic therapy (PDT). Their utility has extended into photothermal therapy (PTT), sonodynamic therapy (SDT), targated drug delivery, bioimaging guided combination therapy, and bioconjugation with biomacromolecules. This review comprehensively explores recent advances in g-C₃N₄ based materials for biomedical applications, focusing on disease treatment, diagnostic imaging, bioconjugation strategies, and combination cancer therapies. We discuss theoretical insights into charge separation, ROS generation, and nanomaterial–biomolecule interactions provide a deeper understanding of the underlying mechanisms. Furthermore, we incorporate the concept of ROS mediated mechanisms in specific cancers, including liver, lung, and breast tumors. We also highlight density functional theory (DFT) and molecular dynamics (MD) simulations that elucidate the bioconjugation of biomacromolecules and drug delivery pathways, thereby guiding the rational design of future therapeutics. Overall, this review provides a critical framework for the development and clinical translation of g-C₃N₄ based nanoplatforms, aiming to enhance cancer diagnosis and treatment efficiency.

In the pursuit of sustainable and biocompatible alternatives to synthetic fibers, Calamus viminalis fibers (CVFs) have emerged as a promising natural resource with significant potential in biomedical and composite applications. This study investigates the chemical, structural, thermal, mechanical, and morphological properties of CVFs to assess their suitability as a reinforcement material and an alternative to a synthetic suture. Chemical analysis revealed that CVFs consist of multiple polysaccharides, including 43.55