Design, fabrication, and evaluation of keratin and pectin incorporated supramolecular structured zero-oxidation state selenium nanogel blended 3D printed transdermal patch

This study investigates the synthesis of selenium nanoparticles (SeNPs), owing to the low cost and abundance of selenium. However, the toxicity of SeNP prompts the development of a selenium nanocomposite (SeNC) containing pectin, keratin, and ferulic acid to improve the bioactivity of Se[0]. Further, incorporating the SeNC in a suitable formulation for drug delivery as a transdermal patch was worth studying. Accordingly, various analytical techniques were used to characterize the SeNPs and the SeNC, confirming successful synthesis and encapsulation. The SeNC exhibited notable particle size of 448.2 ± 50.2 nm, high encapsulation efficiency (98.90 % ± 2.4 %), 28.1 ± 0.45 drug loading, and sustained drug release at pH 5.5. Zeta potential and XPS confirmed the zero-oxidation state. The supramolecular structure was evident from spectral analysis endorsing the semi-crystalline nature of the SeNC and SEM images showcasing flower-shaped structures. Further, the SeNC demonstrated sustained drug release (approx. 22 % at 48 h) and wound-healing potential in L929 fibroblast cells. Subsequently, the SeNC loaded into a gelling agent exhibited shear thinning properties and improved drug release by nearly 58 %. A 3D printed reservoir-type transdermal patch was developed utilizing the SeNC-loaded gel, surpassing commercially available patches in characteristics such as % moisture uptake, tensile strength, and hydrophobicity. The patch, evaluated through permeation studies and CAM assay, exhibited controlled drug release and angiogenic properties for enhanced wound healing. The study concludes that this patch can serve as a smart dressing with tailored functionality for different wound stages, offering a promising novel drug delivery system for wound healing.

A Minor Groove Binder with Significant Cytotoxicity on Human Lung Cancer Cells: The Potential of Hesperetin Functionalised Silver Nanoparticles

Natural drug functionalised silver (Ag) nanoparticles (NPs) have gained significant interest in pharmacology related applications due to their therapeutic efficiency. We have synthesised silver nanoparticle using hesperetin as a reducing and capping agent. This work aims to discuss the relevance of the hesperetin functionalised silver nanoparticles (H-AgNPs) in the field of nano-medicine. The article primarily investigates the anticancer activity of H-AgNPs and then their interactions with calf thymus DNA (ctDNA) through spectroscopic and thermodynamic techniques. The green synthesised H-AgNPs are stable, spherical in shape and size of 10 ± 3 nm average diameter. The complex formation of H-AgNPs with ctDNA was established by UV-Visible absorption, fluorescent dye displacement assay, isothermal calorimetry and viscosity measurements. The binding constants obtained from these experiments were consistently in the order of 104 Mol-1. The melting temperature analysis and FTIR measurements confirmed that the structural alterations of ctDNA by the presence of H-AgNPs are minimal. All the thermodynamic variables and the endothermic binding nature were acquired from ITC experiments. All these experimental outcomes reveal the formation of H-AgNPs-ctDNA complex, and the results consistently verify the minor groove binding mode of H-AgNPs. The binding constant and limit of detection of 1.8 μM found from the interaction studies imply the DNA detection efficiency of H-AgNPs. The cytotoxicity of H-AgNPs against A549 and L929 cell lines were determined by in vitro MTT cell viability assay and lactate dehydrogenase (LDH) assay. The cell viability and LDH enzyme release are confirmed that the H-AgNPs has high anticancer activity. Moreover, the calculated LD50 value for H-AgNPs against lung cancer cells is 118.49 µl/ml, which is a low value comparing with the value for fibroblast cells (269.35 µl/ml). In short, the results of in vitro cytotoxicity assays revealed that the synthesised nanoparticles can be considered in applications related to cancer treatments. Also, we have found that, H-AgNPs is a minor groove binder, and having high DNA detection efficiency.

Exploring the cytotoxicity on human lung cancer cells and DNA binding stratagem of camptothecin functionalised silver nanoparticles through multi-spectroscopic, and calorimetric approach

The influence of nanoparticles inside the human body and their interactions with biological macromolecules need to be explored/studied prior to specific applications. The objective of this study is to find the potential of camptothecin functionalised silver nanoparticles (CMT-AgNPs) in biomedical applications. This article primarily investigates the binding stratagem of CMT-AgNPs with calf thymus DNA (ctDNA) through a series of spectroscopic and calorimetric methods and then analyses the anticancer activity and cytotoxicity of CMT-AgNPs. The nanoparticles were synthesized using a simple one pot method and characterized using UV-Visible, fourier transform infrared (FTIR) spectroscopy, X-ray diffraction and high-resolution transmission electron microscopy (HRTEM). The average size of CMT-AgNPs is 10 ± 2 nm. A group of experimental techniques such as UV-Visible spectrophotometry, fluorescence dye displacement assay, circular dichroism (CD) and viscosity analysis unravelled the typical groove binding mode of CMT-AgNPs with ctDNA. The CD measurement evidenced the minor conformational alterations of double helical structure of ctDNA in the presence of CMT-AgNPs. The information deduced from the isothermal titration calorimetry (ITC) experiment is that the binding was exothermic and spontaneous in nature. Moreover, all the thermodynamic binding parameters were extracted from the ITC data. The binding constants obtained from UV absorption experiments, fluorescence dye displacement studies and ITC were consistently in the order of 10⁴ Mol^-1. All these results validated the formation of CMT-AgNPs-ctDNA complex and the results unambiguously confirm the typical groove binding mode of CMT-AgNPs. An exhaustive in vitro MTT assay by CMT-AgNPs and CMT against A549, HT29, HeLa and L929 cell lines revealed the capability of CMT-AgNPs as a potential anticancer agent.

Unveiling the binding details and esterase-like activity effect of methyl yellow on human serum albumin: spectroscopic and simulation study

The food sector uses methyl yellow (MY) extensively as a colorant. The primary transporter in vivo that influences MY absorption, metabolism, distribution, and excretion is human serum albumin (HSA). Exploring the binding process and looking at how HSA and MY work physiologically at the molecular level is therefore very important. Experiments using steady-state fluorescence and fluorescence lifetimes proved that HSA and MY's quenching mechanisms were static. The HSA-MY complex's binding constant was estimated using thermodynamic parameters to be around 10⁴ M^-1. The hydrophobic forces were a major factor in the binding process, as evidenced by the negative ΔG, positive ΔH, and ΔS, which suggested that this contact was spontaneous. Site tests showed that MY linked to HSA's site I. Circular dichroism and three-dimensional fluorescence analysis revealed that the 1.33% α-helix content dropped and the amino acid microenvironment altered. While HSA's protein surface hydrophobicity decreased when engaging MY, the binding of MY to HSA reduced in the presence of urea. The stability of the system was assessed using molecular modeling. Additionally, HSA's esterase-like activity decreased when MY was present, and Ibf/Phz affected the inhibition mechanism of MY on HSA. These findings offer a distinctive perspective for comprehending the structure and functioning of HSA and evaluating the safety of MY.

Electroanalysis of Ibuprofen and Its Interaction with Bovine Serum Albumin

The current work presents a sensitive, selective, cost-effective, and environmentally benign protocol for the detection of ibuprofen (IBP) by an electrochemical probe made of a glassy carbon electrode modified with Ag-ZnO and MWCNTs. Under optimized conditions, the designed sensing platform was found to sense IBP up to a 28 nM limit of detection. The interaction of IBP with bovine serum albumin (BSA) was investigated by differential pulse voltammetry. IBP-BSA binding parameters such as the binding constant and the stoichiometry of complexation were calculated. The results revealed that IBP and BSA form a single strong complex with a binding constant value of 8.7 × 10¹³. To the best of our knowledge, this is the first example that reports not only IBP detection but also its BSA complexation.

Mycosynthesis of highly fluorescent selenium nanoparticles from Fusarium oxysporum, their antifungal activity against black fungus Aspergillus niger, and in-vivo biodistribution studies

In the past few years, photo-luminescent inorganic materials have been studied extensively as fluorescent sensors, and diagnostic and bioimaging tools. The assessment of photoluminescence (PL) properties of selenium nanoparticles (Se NPs), especially mycosynthesized Se NPs, is still in its infancy. Herein, we have biosynthesized highly dispersed fluorescent Se NPs (42 nm) using endophytic fungus Fusarium oxysporum, and fully characterized them using sophisticated instruments like TEM, XRD, UV–Vis spectrophotometer, FTIR, and PL spectrometer. To determine the therapeutic efficacy and side effect profiles, these crystalline Se NPs were radiolabeled with technetium-99m (^99mTc) and their biodistribution and renal clearance times were investigated in the normal Wister rat. The results showed that these Se NPs may be useful for targeting the lungs and liver dysfunction as significant accumulation of these NPs was observed in the liver (approx. 19.47 ± 4%) and lungs (at 6 ± 1%) after 10 min of post-injection. Quick circulation and the presence of Se NPs in kidney (3.8 ± 2%) also suggested the easy excretion of these NPs from the body through urinary tract. Furthermore, the antioxidant activity of Se NPs (IC₅₀, 159.5 μg/mL) has been investigated using DPPH free radical scavenging assay with scavenging efficacy of 80.4% where ascorbic acid (IC₅₀, 5.6 μg/mL) was used as a positive control. Additionally, the microscopic study of the inhibition zone encircled around Se NPs confirmed their strong antifungal and antisporulant activity against the black fungus Aspergillus niger.

Development, characterization and in vitro bile salts binding capacity of selenium nanoparticles stabilized by soybean polypeptides

The paper presents the positive effect of soybean polypeptides (SP) on the stability and the potential hypolipidemic effect of selenium nanoparticles (SeNPs). After preparing SeNPs, SP with different molecular weight were introduced to stabilize SeNPs. We found that the SP with molecular weight >10 kDa (SP5) had the best stabilizing effect on SeNPs. We inferred that the steric resistance resulting from the long chains of SP5 protected SeNPs from collision-mediated aggregation, and the electrostatic repulsions between SP5 and SeNPs also played a positive role in stabilizing SeNPs. The as-prepared SP5-SeNPs were spherical, amorphous and zero valent. It was proved that SeNPs were bound with SP5 through O- and N- groups in SP5, and the main forces were hydrogen bonds and van der Waals forces. The bile salts binding assay showed that the SP5-SeNPs exhibited a high binding capacity to bile salts, which indicated their potential in hypolipidemic application.

Selenium Nanoparticles Biosynthesized by Pantoea agglomerans and Their Effects on Cellular and Physiological Parameters in the Rainbow Trout Oncorhynchus mykiss

Simple Summary

Nanoparticles (Nps), new biotechnological tools, possess unique physical and chemical properties and are increasingly being used in several fields, such as manufacture, medicine and veterinary medicine. In this work, we evaluated the effects of selenium (Se) nanoparticles stabilized with L-Cysteine (Se⁰Nps/L-Cys) as a nutritional supplement, to modulate immunological, oxidative status, and productive parameters in O. mykiss. The results demonstrated that Se⁰Nps/L-Cys showed less toxicity and higher antioxidant activity than Se⁰Nps and Na₂SeO₃. The Se⁰Nps/L-Cys, as a dietary supplement, had a significantly better effect on both immunological and physiological parameters, causing improvements at the productive level of O. mykiss when compared with Se⁰Nps and Na₂SeO₃. We concluded that Se⁰Nps sythetised by P. agglomerans, used as dietary supplement, is an environmentally friendly and promising alternative for nutritional supplementation for O. mykiss.

Abstract

The applications of nanoparticles (Nps) as food additives, health enhancers, and antimicrobials in animal production are increasing. The aim of this study was to evaluate the effect of selenium (Se) nanoparticles (Se⁰Nps) stabilized with L-cysteine (Se⁰Nps/L-Cys), as a nutritional supplement, on immunological, oxidative status, and productive parameters in O. mykiss. TEM and SEM-EDS showed the accumulation of spherical Se⁰Nps entirely composed by elemental selenium (Se⁰) as intracellular and extracellular deposits in Pantoea agglomerans UC-32 strain. The in vitro antioxidant capacity of Se⁰Nps/L-Cys was significant more efficient ROS scavengers than Se⁰Nps and Na₂SeO₃. We also evaluate the effect of Se⁰Nps/L-Cys on cell viability and oxidative stress in RTgill-W1, RTS-11, or T-PHKM Oncorhynchus mykiss cell lines. Se⁰Nps/L-Cys showed less toxic and high antioxidant activity than Se⁰Nps and Na₂SeO₃. Finally, the dietary Se⁰Nps/L-Cys had a significant better effect on both plasma lysozyme and respiratory burst activity (innate immune response), on tissular Gpx activity (oxidative status), and on well-being (productive parameter) of O. mykiss when it is compared to Se⁰Nps and Na₂SeO₃. Se⁰Nps/L-Cys is a promising alternative for nutritional supplement for O. mykiss with better performance than Na₂SeO₃ and Se⁰Nps, ease to implementation, and reduced environmental impact.

Selenium-Functionalized Corn Starch as a Biodegradable GPx Mimic with High Catalytic Performance

Selenium-functionalized starch (Se-starch80) is one of the main functional foods used for selenium supplementation. In traditional agriculture, Se-starch has some deficiencies such as long growth cycle and unstable selenium content that prevent its antioxidant performance. In this study, Se-starch was prepared by the nucleophilic addition between NaSeH and carbon-carbon double bond of octenyl succinic anhydride waxy corn starch ester (OSA starch). Some techniques such as ¹HNMR, XPS, SEM-EDS, XRD and FT-IR were used to characterize the relevant samples and the results showed that the modification did not destroy the starch framework significantly and the catalytic center (negative divalent selenium) was anchored on the starch framework. The intensive distribution of catalytic center on the starch surface and the hydrophobic microenvironments derived from the OSA chains furnished the Se-starch80 with a high GPx-like catalytic activity (initial reaction rate = 3.64 μM/min). This value was about 1.5 × 10⁵ times higher than that of a typical small-molecule GPx mimic (PhSeSePh). In addition, the Se-starch80, without any cytotoxicity, showed a saturated kinetic catalytic behavior that is similar to a typical enzyme. This work exemplifies a biodegradable selenium-functionalized polymer platform for the high-performing GPx mimic.

Discussions of Fluorescence in Selenium Chemistry: Recently Reported Probes, Particles, and a Clearer Biological Knowledge

In this review from literature appearing over about the past 5 years, we focus on selected selenide reports and related chemistry; we aimed for a digestible, relevant, review intended to be usefully interconnected within the realm of fluorescence and selenium chemistry. Tellurium is mentioned where relevant. Topics include selenium in physics and surfaces, nanoscience, sensing and fluorescence, quantum dots and nanoparticles, Au and oxide nanoparticles quantum dot based, coatings and catalyst poisons, thin film, and aspects of solar energy conversion. Chemosensing is covered, whether small molecule or nanoparticle based, relating to metal ion analytes, H2S, as well as analyte sulfane (biothiols-including glutathione). We cover recent reports of probing and fluorescence when they deal with redox biology aspects. Selenium in therapeutics, medicinal chemistry and skeleton cores is covered. Selenium serves as a constituent for some small molecule sensors and probes. Typically, the selenium is part of the reactive, or active site of the probe; in other cases, it is featured as the analyte, either as a reduced or oxidized form of selenium. Free radicals and ROS are also mentioned; aggregation strategies are treated in some places. Also, the relationship between reduced selenium and oxidized selenium is developed.

Investigation of interaction between biogenic selenium nanoparticles and human serum albumin using microwave plasma optical emission spectrometry operating in a single-particle mode

Abstract

Characterization of selenium nanoparticles and selenium nanoparticle–human serum albumin conjugates prepared in nanopowder form, their elemental composition, and particle size distribution were investigated with a microwave plasma optical emission spectrometry operating in a single-particle mode. This new analytical technique was used for the first time to examine the molecular interaction between selenium nanoparticles and human serum albumin regarding potential biomedical applications of selenium nanoparticles. Nanopowder sample was introduced to a helium plasma by pneumatic nebulization based on fluidized bed approach and measured with a time resolution of 20 ms. Both selenium nanoparticles and selenium nanoparticle–human serum albumin conjugates were characterized by observation of synchronous signals from different particle components. Plots of the time correlation between Se and C signals for all particles in selenium nanoparticles and selenium nanoparticle–human serum albumin conjugates samples differed from each other in degree of correlation and synchronicity of recorded signals. The interaction between selenium nanoparticles and human serum albumin was confirmed using Bradford assay. For selenium nanoparticles synthesized using yeast cells, the percentage of bound protein was only of 4%, whereas for selenium nanoparticles synthesized using yeast extract as a stabilizing agent it was 16%.

Graphic abstract

Investigating the interaction between DNA-templated gold nanoclusters and HSA via spectroscopy

Gold nanoclusters (AuNCs) have attracted great attention in bioimaging and drug transportation due to their biocompatibility, but a few studies have shown their potential toxicity.

Computational and spectroscopic analysis of interaction between food colorant citrus red 2 and human serum albumin

The main aim of this work was to gain insight into the binding properties between a food colorant, citrus red 2 (CR), and human serum albumin (HSA), which is the predominant protein in blood plasma. Here, computer simulations and multiple spectroscopies were applied to predict and characterize the interaction between CR and HSA. Docking and molecular dynamics presented a stable binding configuration with low fluctuations. Fluorescence spectroscopy and lifetime results suggested that the CR–HSA combination undergoes static quenching mechanism with binding constant of 10⁵ L/mol. Displacement analysis showed the binding of CR at site I of HSA, which agrees with the docking results. The binding process occured spontaneously and was mainly driven by electrostatic interactions. Synchronous fluorescence and circular dichroism measurements demonstrate the changes in the microenvironment residues and α-helix contents of HSA induced by CR. The computational and experimental techniques are complementary to clearly understand the food colorant transportation and bioaccumulative toxicity in the human body.

Photophysical and thermodynamic evaluation on the in vitro and in silico binding profile of Camptothecin with DNA

Camptothecin (CMT) is an anti-tumour alkaloid drug exhibiting selective topoisomerase-I inhibitory activity by eventually hindering dynamic functions of DNA duplex via initiating apoptosis. Unravelling the binding mechanism of CMT with bio macromolecular systems can offer fundamental information regarding the mechanism of actions which can lead to the design of rational proactive drugs. This study endeavoured the binding interactions of CMT with calf thymus DNA (ct-DNA) along with the structural alterations attained by the DNA duplex owing to CMT interactions through multi-spectroscopic, calorimetric and molecular docking studies. The UV-visible absorbance and fluorescence quenching studies revealed the binding strength of CMT with ct-DNA, evident from the binding constants K₁ = 3.79 × 10³ M^-1 and Kq = 2 × 10³ M^-1. The time-resolved lifetime measurements inferred that the quenching was static due to the non-fluorescent ground state complex formation. The dye displacement study, temperature melting and viscosity measurements established a typical non-intercalative binding mode of CMT with ct-DNA. The binding isotherm deduced from ITC was found to be spontaneous and exothermic exerting a promising ΔG value of -6.2 kcal mol^-1. The thermal kinetic parameters implied that the forces primarily involved in the CMT-ct-DNA complexation are hydrogen bonding and van der Waals interactions. Moreover, the structural alterations of DNA duplex reflected in the CD and FTIR spectra could undeniably confirm the groove binding manner of CMT. The in silico extra precision docking study explored more accurate molecular illustrations of sequence specific minor groove binding mechanism evolved between CMT and DNA corroborating well with the experimental results. These innovative findings may shorten the path towards the development of novel and more effective CMT drug derivatives.

Determination of interactions between human serum albumin and niraparib through multi-spectroscopic and computational methods

The interactions between 2-{4-[(3S)-piperidin-3-yl] phenyl}-2H-indazole-7-carboxamide (niraparib) and human serum albumin (HSA) were investigated through fluorescence and computational studies. Fluorescence experiments showed that the static quenching mechanism and the binding constant of the HSA-niraparib system at a single binding site was approximately 4 × 10⁴ L mol^-1. Thermodynamic constants indicated that the binding of niraparib to HSA was mainly driven by electrostatic interactions. Competition experiments and molecular docking simulations revealed that niraparib bound to site III of HSA. Synchronous fluorescence and Fourier transform infrared spectroscopy (FT-IR) results suggested that interactions between niraparib and HSA could affect the conformation and microenvironment of HSA. Circular dichroism (CD) measurements revealed that the α-helix contents of HSA negligibly increased after binding with niraparib. Molecular dynamics simulations demonstrated the stability of the binary HSA-niraparib system and confirmed that electrostatic forces accounted for the dominant contribution to system energy between HSA and niraparib.

Differences between the binding modes of enantiomers S/R-nicotine to acetylcholinesterase

Nicotine causes neurotoxic effects because it quickly penetrates the blood–brain barrier after entering the human body. Acetylcholinesterase (AChE) is a key enzyme in the central and peripheral nervous system associated with neurotoxicity. In this study, a spectroscopic method and computer simulation were applied to explore the mode of interaction between AChE and enantiomers of nicotine (S/R-nicotine). Fluorescence spectroscopy showed that the quenching mechanism of endogenous fluorescence of AChE by S/R-nicotine was static, as confirmed by the time-resolved steady-state fluorescence. The binding strength of both nicotine to AChE was weak (S-AChE: K_a = 80.06 L mol⁻¹, R-AChE: K_a = 173.75 L mol⁻¹). The main driving forces of S-AChE system interaction process were van der Waals force and hydrogen bonding, whereas that of R-AChE system was electrostatic force. Computer simulations showed that there were other important forces involved. S/R-Nicotine had a major binding site on AChE, and molecular docking showed that they bound mainly to the cavities enclosed by the active sites (ES, PAS, OH, AACS, and AP) in the protein. UV-vis spectroscopy and 3D spectroscopy indicated that nicotine significantly affected the microenvironment of Trp amino acids in AChE. The CD spectra indicated that S-nicotine increased the α-helical structure of AChE, but the overall conformation did not change significantly. By contrast, R-nicotine significantly changed the secondary structure of AChE. 5,5′-Dithiobis-2-nitrobenzoic acid (DTNB) method indicated that S and R nicotine produced different degrees of inhibition on the catalytic activity of AChE. Both experimental methods and computer simulations showed that R-nicotine had a significantly higher effect on AChE than S-nicotine. This research comprehensively and systematically analyzed the mode of interaction between nicotine and AChE for neurotoxicity assessment.

Study on the binding modes of AChE to S/R-nicotine.

Interactions between the antiviral drug telaprevir and human serum albumin: a combined study with spectroscopic methods and molecular modeling

The binding mechanism between telaprevir and human serum albumin was explored by combining spectroscopic methods and molecular dynamics simulations.