ZnO nanoparticles, as fabricated using
Ocimum tenuiflorum
leaf extract, have been investigated for their photocatalytic and antimicrobial activities. However, the ZnO nanoparticles were synthesized ...using precursor, Zn(CH
3
COO)
2
·2H
2
O at different concentrations (5, 10 and 50 mmol kg
−1
) at 70 °C and pH 11.5. The synthesized materials were characterized by employing Fourier transform infrared spectroscopy, UV–Visible, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy techniques. As recorded from UV–Visible studies, there was a drastic decrease in the energy band gap value (
E
g
) from 3.63 to 3.20 eV with the concentration of precursor, Zn(CH
3
COO)
2
·2H
2
O. The synthesized materials were examined for their photocatalytic activity towards the degradation of methyl orange dye and also for antibacterial action against
Bacillus subtilis
,
Staphylococcus aureus
and
Escherichia coli
pathogenic bacteria.
In this study, a microwave-assisted method was used to encapsulate dual doped nickel-copper titanium dioxide (TiO2) nanoparticles (Ni-Cu TNPs) with polymer polyvinylpyrrolidone (PVP) and plant ...Tinospora Cordifolia (TC). The catalytic efficiency of encapsulated TNPs was performed through photocatalytic activity against Methyl Orange (MO) and Methylene Blue (MB) dyes as considered as water pollutants released by textiles industries. Also, these encapsulated TNPs were incubated in scavenging activity to eliminate the free radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The physicochemical properties of the encapsulated TNPs were analyzed using different characterization techniques. X-Ray Diffraction (XRD revealed that the encapsulated dual doped Ni-Cu TNPs had a tetragonal crystal lattice structure. The scanning electron microscopy (SEM) confirms the spherical morphology of encapsulated dual doped Ni-Cu TNPs with an average particle size ranging from 33 to 41 nm. The bandgap of the encapsulated dual doped Ni-Cu TNPs was found to be between 3.47 and 3.54 eV. Under UV radiation, the photocatalytic activity was performed with using control experiment and using encapsulated dual doped Ni-Cu TNPs against MO and MB dyes. The rate of degradation reached up to 99% for both dyes on increasing with an increase in TNPs catalyst dosage. Also, the encapsulated dual doped Ni-Cu TNPs demonstrated antioxidant activity of up to 93% against the DPPH assay.
This research paper is devoted to measure the activity contents of natural radionuclide, like, radium (
226
Ra), thorium (
232
Th) and potassium (
40
K) in the soil gathered along the Jwalamukhi ...thrust of Himachal Pradesh, North Western Himalayas, India. NaI(Tl) Scintillator detector was utilized for the estimation of activity content. The activity concentration of
226
Ra,
232
Th and
40
K for some of the soil samples have been observed to be above the global normal mean values. The outcomes acquired for indoor and outdoor effective dosage are well below the normal international and national proposed results. The determined values of external hazard (H
ex
) for studied locations are less than unity, therefore; samples assembled from these regions are safe from a health hazard point of view and can be utilized as a construction purposes without producing any radio-logical hazard to human beings. The average estimations of radium equivalent activity were found to be within the limits suggested by Organization for Economic Cooperation and Development (OECD). Radon (
222
Rn) and thoron (
220
Rn) exhalation rates have also been calculated and discussed.
In the realm of biomedical applications, the inclusion of plant-derived components stands out as a critical consideration due to their non-toxic nature and antioxidant properties. In our research, we ...opt for Colocasia esculenta plant extract, utilizing microwave technology to create dually doped ZnO nanopowder with copper (Cu) and cerium (Ce). Authors employ XRD analysis to explore the structural attributes and crystallite size of the nanoparticles, which are found to be within the range of 16–19 nm. The surface and internal characteristics of these nanoparticles are precisely scrutinized using SEM-EDS and TEM characterization techniques. Additionally, ultraviolet-visible spectroscopy is utilized to determine the forbidden energy gap of the samples, providing insights into their potential applications in UV-protected devices. The synthesized nanoparticles exhibit significant antibacterial and antioxidant properties, highlighting their adaptability for various biomedical uses.
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Aggregation behavior of conventional surfactants; SDS (anionic) and CTAB (cationic) in aqueous medium has been investigated in the presence of anti-HIV drugs; Emtricitabine (ECT) and Lamivudine (LMV) ...using conductometry, UV–Visible spectroscopy, and fluoroscence measurements over a temperature range of T = (298.15–313.15) K. The CMC values calculated from the conventional study i.e. conductance measurements corroborate very well with those obtained from spectroscopic techniques i.e. UV–Visible spectroscopy and fluorometry. The calculated CMC values have been used to determine thermodynamic parameters such as standard changes in enthalpy of micellization (ΔHmo), entropy of micellization (ΔSmo) and free energy of micellization (ΔGmo) using pseudo-phase separation model. These parameters have been analyzed in terms of the hydrophobic-hydrophilic interactions present in the surfactant-water-drug ternary system. It has been observed from the thermodynamic analysis that both the drugs favor micellization of studied ionic surfactants (SDS and CTAB) in aqueous medium, with Lamivudine exhibiting a more pronounced effect. Further, the micellar stability of studied systems has been analyzed in terms of enthalpy-entropy compensation graphs. This in-depth exploration of anti-HIV drug-surfactant interactions holds promising implications for enhancing pharmaceutical formulations in the context of HIV infection diseases.
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G protein-coupled receptors (GPCRs) are embedded in phospholipids that strongly influence drug-stimulated signaling. Anionic lipids are particularly important for GPCR signaling complex formation, ...but a mechanism for this role is not understood. Using NMR spectroscopy, we explore the impact of anionic lipids on the function-related conformational equilibria of the human A
adenosine receptor (A
AR) in bilayers containing defined mixtures of zwitterionic and anionic phospholipids. Anionic lipids prime the receptor to form complexes with G proteins through a conformational selection process. Without anionic lipids, signaling complex formation proceeds through a less favorable induced fit mechanism. In computational models, anionic lipids mimic interactions between a G protein and positively charged residues in A
AR at the receptor intracellular surface, stabilizing a pre-activated receptor conformation. Replacing these residues strikingly alters the receptor response to anionic lipids in experiments. High sequence conservation of the same residues among all GPCRs supports a general role for lipid-receptor charge complementarity in signaling.
In this current investigation, we elucidated the microwave-assisted green synthesis of 90:10, 80:20, and 70:30 CuO–Co3O4 nanocomposites (NCs) from Ipomoea carnea leaf extract, manifesting their ...remarkable antibacterial, photocatalytic, and antioxidant capabilities. The spectroscopic techniques of XRD, SEM, EDX, TEM, FTIR, and UV–visible spectroscopy were employed to validate the formation of the synthesized NCs. SEM and TEM images revealed distinctive snowball-rod and distorted spherical structures in the synthesized nanocomposites, with average particle sizes of 33.36, 26.17, and 29.10 nm. The estimated energy band gap values were 1.20, 1.40, and 1.50 eV for the respective nanocomposites. The well diffusion method was utilized to explore the zone of inhibition (ZOI) against bacteria, namely Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. The nanocomposites, specifically the 90:10 and 80:20 CuO–Co3O4 blends, exhibited a noteworthy Zone of Inhibition (ZOI) during testing against B. subtilis, with approximate values of 34.76 ± 0.23 and 33.33 ± 0.32 mm, respectively. Furthermore, the photocatalytic potential has been investigated against the dyes Malachite green (MG) and Congo red (CR). Notably, the 90:10 NCs displayed an exceptional photodegradation rate of 97.69 % for MG and 95 % for CR within a mere 45 min. Moreover, the 70:30 NCs exhibited a commendable radical scavenging activity of approximately 97.53 % at a concentration of 800 μg/mL, while ascorbic acid, used as a standard, displayed a scavenging activity of 98.63 %. These investigations unveil the environmentally friendly, innovative, and cost-effective attributes of CuO–Co3O4 NCs derived from Ipomoea carnea leaf extract, which demonstrated excellent antibacterial, photocatalytic, and antioxidant properties.
This research intends to formulate Ocimum sanctum mediated pure and transition metal (Co2+/Cu2+/Zn2+) doped magnesium oxide nanoparticles (MgO NPs). The cubic structure of so synthesized MgO NPs was ...confirmed by XRD analysis. As per UV–visible spectral analysis, band gap (Eg) is tuned upon doping; doping with Co, Cu and Zn, their respective Eg are 1.65 eV, 1.96 eV and 3.66 eV in relation to MgO, Eg = 3.50 eV. The average particle size decreased from 17 nm for MgO NPs to 8–13 nm for doped MgO NPs, based on TEM analysis. EDX and XPS analysis verified the presence of Mg, O and dopants, Co, Cu and Zn in synthesized NPs. SEM investigations showed that NPs are agglomerated and spherical. Zn–MgO NPs outperform Co/Cu doped MgO NPs in their photocatalytic efficacy and comparative degradation of methyl orange (MO) and malachite green (MG) dyes confirmed that they are more efficient in degrading MG. Antibacterial investigation revealed that Cu and Zn doped MgO NPs are efficient antibacterial agents against B. subtilis and E. coli than MgO NPs. In this study, Co–MgO NPs were ineffective as antibacterial agents. S. aureus was found resistant to all NPs. Using the DPPH radical scavenging technique, these biosynthesized nanoparticles displayed 62–69 % antioxidant activity.
Although the human pathogen,
(
), is strictly aerobic and requires efficient supply of oxygen, it can survive long stretches of severe hypoxia. The mechanism responsible for this metabolic ...flexibility is unknown. We have investigated a novel mechanism by which hemoglobin O (HbO), operates and supports its host under oxygen stress.
We discovered that the HbO exists in a phospho-bound state in
and remains associated with the cell membrane under hypoxia. Deoxy-HbO carries an autokinase activity that disrupts its dimeric assembly into monomer and facilitates its association with the cell membrane, supporting survival and adaptation of
under low oxygen conditions. Consistent with these observations, deletion of the
O gene in
bacillus Calmette-Guerin, which is identical to the
O gene of
, attenuated its survival under hypoxia and complementation of the
O gene of
rescued this inhibition, but phosphorylation-deficient mutant did not. These results demonstrated that autokinase activity of the HbO modulates its physiological function and plays a vital role in supporting the survival of its host under hypoxia.
Our study demonstrates that the redox-dependent autokinase activity regulates oligomeric state and membrane association of HbO that generates a reservoir of oxygen in the proximity of respiratory membranes to sustain viability of
under hypoxia. These results thus provide a novel insight into the physiological function of the HbO and demonstrate its pivotal role in supporting the survival and adaptation of
under hypoxia.
SARS-CoV-2 claimed numerous lives and put nations on high alert. The lack of antiviral medications and the small number of approved vaccines, as well as the recurrence of adverse effects, ...necessitates the development of novel treatment ways to combat COVID-19. In this context, using databases such as PubMed, Google Scholar, and Science Direct, we gathered information about nanotechnology’s involvement in the prevention, diagnosis and virus-like particle vaccine development. This review revealed that various nanomaterials like gold, polymeric, graphene and poly amino ester with carboxyl group coated magnetic nanoparticles have been explored for the fast detection of SARS-CoV-2. Personal protective equipment fabricated with nanoparticles, such as gloves, masks, clothes, surfactants, and Ag, TiO2 based disinfectants played an essential role in halting COVID-19 transmission. Nanoparticles are used not only in vaccine delivery, such as lipid nanoparticles mediated transport of mRNA-based Pfizer and Moderna vaccines, but also in the development of vaccine as the virus-like particles elicit an immune response. There are now 18 virus-like particle vaccines in pre-clinical development, with one of them, developed by Novavax, reported being in phase 3 trials. Due to the probability of upcoming COVID-19 waves, and the rise of new diseases, the future relevance of virus-like particles is imperative. Furthermore, psychosocial variables linked to vaccine reluctance constitute a critical problem that must be addressed immediately to avert pandemic.
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