FTIR Spectroscopy Research Articles

Synthesis and characterization of polyaniline/TiO2 nanocomposite based ammonia gas sensor

Pure TiO2 nanoparticles were synthesized using the sol-gel method and polyaniline (PANI), while PANI/TiO2 (content TiO2:25 % and 50 %) nanocomposites were synthesized by using in-situ chemical oxidative polymerization method. X-RD, FTIR spectroscopy, and scanning electron microscopy (SEM) were used for the structural analysis, elemental composition, and surface morphology. The XRD patterns of PANI/TiO2(25 %,50 %) composites reveals that the relative intensity of diffracted peaks increases with increasing the content of TiO2 indicating an increase of crystallinity in such case. FTIR confirmed the presence of functional groups in the nanocomposite. In SEM surface morphology observed that highly porous nanograins are formed. The average particle sizes of PANI/TiO2(25 %) 339 nm and PANI/TiO2(50 %) 196 nm were obtained. The resistance change response of nanocomposite material were done by using a static two-probe unit by exposure to ammonia (NH3) gas. The maximum sensitivity of PANI/TiO2(50 %) nanocomposite was achieved on 500 ppm (parts per million) of ammonia gas at 40 °C. The fast response time (20 s.), and recovery time (28 s.) has obtained.

Gamma-ray shielding effectiveness, optical, mechanical, dielectric properties of nanofiller-reinforced PVA/PVP polymeric blend nanocomposites

The aqueous solution cast method was used to create the biodegradable polymer nanocomposite (PNC) films from a blend of poly (vinyl alcohol) PVA and poly (vinyl pyrrolidone) PVP (70/30 wt %) and Fe2O3 nanoparticles (NPs). These PNC films were characterized using X-ray diffraction, scanning electron microscopy SEM, Fourier transform infrared spectroscopy FTIR, and ultraviolet-visible spectroscopy. XRD and FTIR results indicate that Fe+ 3 NPs interact with the host polymer. Optical, electrical, mechanical, and radiation shielding measurements were performed on the PNC films. From the optical measurements, the indirect optical band gap drops from 4.86 eV for the pure blend to 4.26 eV at the greatest NPs concentration. Optical limiting characterization shows that the output power of He-Ne and solid-state green laser beams is reduced from 22.98 to 3.6 mW and 6.59 to 1.4 mW, respectively, when the Fe2O3 NPs content in the blend matrix is increased to 6 wt %. The NGCal software was utilized to calculate nuclear radiation shielding properties. The findings demonstrated that when the concentration of Fe2O3 rose, the PNC films half-value layer and mean free path decreased. Mechanical measurements demonstrate that increasing the Fe2O3 content significantly improves nanocomposite films’ yield and tensile strength. Tensile strength is measured at 27.03 MPa for the composite film containing 6 wt % Fe2O3, which is significantly higher than the 8.66 MPa of the pure (PVA-PVP) film. Compared to the other samples under examination, the 6 wt % Fe2O3 sample yielded the best results (based on the analyzed optical, electrical, mechanical, and radiation shielding properties).

Innovative biopolymers composite based thin film for wound healing applications

Efficient wound and burn healing is crucial for minimising complications, preventing infections, and enhancing overall well-being, necessitating the development of innovative strategies. This study aimed to formulate a novel thin film combining chitosan, carboxymethyl cellulose, tannic acid, and beeswax for improved wound healing applications. Several formulations, incorporating chitosan, carboxymethyl cellulose, tannic acid, and beeswax in various percentages, were utilized to deposit thin films via the solvent evaporation technique, Mechanical properties, morphology, antioxidant activity, antibacterial efficacy, and wound healing potential were evaluated. The optimized thin film (M4), composed of 2% chitosan, 2% carboxymethyl cellulose, and 1% tannic acid, along with 0.2% glycerol and 0.2% tween80, exhibited a thickness of 39.0 ± 1.14 μm and a tensile strength of 0.275 ± 0.003 MPa. It demonstrated a swelling degree of 283.0 ± 2.0% and a drug release capacity of 89.4% within 24 h. The film also showed a low contact angle of 40.5° and a water vapour transmission rate of 1912.25 ± 13.10 g m−2 0.24 h−1. FT-IR spectroscopy indicated that chitosan and carboxymethyl cellulose were cross-linked through amide linkages, with tannic acid occupying the interstitial spaces and hydrogen bonding stabilizing the structure. Microscopy of M4 revealed a uniform morphology. The film exhibited strong antioxidant activity of (95.17 ± 0.02%) and antibacterial efficiency (80.8%) against S. aureus. In a rabbit model, the film significantly enhanced burn and excision wound recovery, with 90.0 ± 3.3% healing for burns and 88.85 ± 1.7% for infected wounds by day 7. Complete skin regeneration was observed within 10–12 days. The M4 thin film demonstrated exceptional mechanical properties and bioactivity, offering protection against pathogens and promoting efficient wound healing. These findings suggest its potential for further investigation in treating various infections and its role in developing novel therapeutic interventions.

Influence of Y2O3 Concentration on the Optical Properties of Multicomponent Glasses and Glass–Ceramics

The optical properties and structural characterization of multicomponent silicate glasses of low Al2O3 and different Y2O3 concentrations have been studied. These glasses have also been crystallized to obtain glass–ceramic materials, and their properties have been characterized. The obtained glasses were transparent and their refractive indexes increased with Y2O3 concentration. After a heat treatment at 930 °C for 10 min, these glasses maintained their transparency, but a brown color appeared, and after 30 min, those glasses with high Y2O3 concentrations turned opaque or white in color. These processes of crystallization for obtaining the new glass–ceramics have been studied by means of FTIR and Raman spectroscopies, and the crystallized materials were characterized with XRD and FE-SEM techniques. These glasses and glass–ceramics have also been characterized by means of UV–vis spectroscopy, and the corresponding optical properties (reflectance, color, band-gap) have been determined as a function of the Y2O3 concentrations and the structural properties.

Water-Soluble Intracellular Polysaccharides (IPSW-2 to 4) from Phellinus igniarius Mycelia: Fractionation, Structural Elucidation, and Antioxidant Activity.

Phellinus igniarius is a medicinal fungus. Nonetheless, research on its water-soluble intracellular polysaccharides (IPSW-2 to 4) fractionation, structural elucidation, and antioxidant activity is limited. In this study, water-soluble intracellular polysaccharides (IPSW-2 to 4) were extracted and fractionated from P. igniarius mycelia, and their antioxidant and structural properties were assessed using GC-FID, GC-MS, FTIR, and NMR spectroscopy (1H and 13C). In the water-eluted P. igniarius polysaccharide fractions (IPS30W, IPS60W, and IPS80W) of anion-exchange chromatography, the polysaccharide content was 79.05%, 68.25%, and 62.06%, with higher yields of 25.07%, 21.38%, and 20.34%, respectively. In contrast, the salt (NaCl) elution fractions (IPS30S1, IPS60S1, IPS60S2, and IPS80S1) of anion-exchange chromatography had lower polysaccharide content and yield. Hence, water elution fractions (IPS30W, IPS60W, and IPS80W) were selected for further purification. After repeated purification using size-exclusion chromatography, IPSW-2 to 4 were obtained with a yield of 8% to 15.83%. The IPSW-2 to IPSW-4 structures were elucidated, and they showed no triple helical conformation. Based on periodate oxidation, Smith degradation, methylation analysis, and 1H and 13C NMR spectroscopy, the primary structures of IPSW-2, IPSW-3, and IPSW-4 were all glucan, with the main chain consisting of (1→6)-α-D-Glcp, (1→3,4)-α-D-Glcp, and (1→3, 6)-α-D-Glcp, with α-D-Glcp as a side chain. Finally, antioxidant analysis showed that IPS30W, IPS60W, and IPS80W were all more capable of scavenging superoxide anions than the polysaccharides of Phyllostachys (13.8%) and floribunda (15.1%) at the same concentration (0.40 mg/mL). This will serve as a guide for the development of functional foods.

Elaboration of newly synthesized tetrahydrobenzo[b]thiophene derivatives and exploring their antioxidant evaluation, molecular docking, and DFT studies

Herein, 2-amino-6-(tert-butyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (1) was synthesized in excellent yield through gewald reaction in multi components one pot reaction. Compound 1 was utilized as a building block to synthesize a new group of tetrahydro benzo[b] thiophene congeners. The chemical structure of all the novel tetrahydro benzo[b]thiophene derivatives were elucidated through the melting point, elemental analysis, FT-IR, 1H-NMR, and mass spectroscopy. Furthermore, the total antioxidant capacity (TAC) of all the newly synthesized heterocyclic derivatives was evaluated according to the phosphomolybdenum method using ascorbic acid as standard. The findings revealed that compounds 1, 16, and 17 demonstrated significant antioxidant potency comparable to that of ascorbic acid. This suggests the potential of these heterocycles as promising candidates for antioxidant drugs in the treatment of oxidative stress-related diseases. Finally, molecular docking was conducted to study the binding affinity for the most potent antioxidant compounds 1, 16, 17 and ascorbic acid inside the interactions of compounds 1, 16, and 17 with the Keap1 (Kelch-like ECH-associated protein 1) protein (PDB: 7C5E), compared to the co-crystallized ligand triethylene glycol (PGE) and ascorbic acid as a reference drug for antioxidants. DFT calculations and global descriptors were calculated for the most potent compounds to correlate the relation between chemical structure and reactivity.

Characterization of PbMo0.3W0.7O4 Crystal: A Potential Material for Photocatalysis and Optoelectronic Applications

AbstractPbMo0.3W0.7O4 semiconductor crystal, which contains the balanced ratios of Mo and W, is grown for the first time by Czochralski method. The structural and optical properties of the crystal are investigated in detail in the present study. Structural analysis shows that crystal has tetragonal structure like PbMoO4 and PbWO4 compounds. The optical characteristics are studied by transmission, Raman, FTIR and photoluminescence methods. The bandgap energy is found to be 3.18 eV, and the positions of the conduction and valence bands are determined. The vibrational characteristics are studied by means of Raman and FTIR spectroscopy techniques. Photoluminescence spectrum presents three peaks around 486, 529, and 544 nm which fall into the green emission spectral range. Taking into account the properties of the compound, it is stated that PbMo0.3W0.7O4 (or Pb(MoO4)0.3(WO4)0.7) has the potential to be used in water splitting applications and optoelectronic devices that emit green light.

Differentiation and quantification of bovine and pork gelatin using UPLC-QTOF and ATR-FTIR spectroscopy: Addressing challenges in mixed gelatin analysis and detection

The amino acid sequence dictates protein folding and spatial structure, essential for understanding their behavior. Gelatin, important in industry and biomedicine, demands accurate source authentication due to ethical and dietary concerns. This study explores differentiating and quantifying bovine and pork gelatin using UPLC-QTOF and ATR-FTIR spectroscopy. UPLC-QTOF identified distinct ions for pure bovine (m/z + 962.1471, NRLHFFK) and pork gelatin (m/z + 653.0289, YNEVK) but struggled with mixed gelatins due to protein-protein interactions altering peptide ion profiles. ATR-FTIR was employed to leverage ethanol's differential effects on gelatin's amide bands for quantifying pork gelatin contamination in bovine gelatin. The method showed a strong linear correlation (R2 = 0.9994) with contamination levels and amide band transmission, with detection and quantification limits of 0.85 and 2.85 mg/100 mg, respectively. It effectively identified pork gelatin in halal candy, with recovery rates from 50.05 % to 103.69 %, highlighting ATR-FTIR's potential for accurate gelatin analysis.

Effect of the heat treatment on the physicochemical characteristics of rubberwood: Results of thermal analysis and FTIR spectroscopy

Heat treatment is an environmentally friendly method used to improve properties of rubberwood. In this work, the changes in the chemical composition, thermal behavior and thermal degradation kinetics of heat-treated Hevea brasiliensis (rubber tree) were evaluated using thermogravimetry, differential scanning calorimetry, and Fourier transform infrared spectroscopy. The rubberwood samples were exposed to temperatures of 180 °C and 220 °C in air under atmospheric pressure for durations of 15 25 and 35 h. Thermal analysis revealed degradation of hemicelluloses, an increase in the relative proportions of cellulose and lignin in heat-treated rubberwood. The thermal decomposition of rubberwood heat-treated at 220 °C started at a higher temperature compared to untreated wood. A shift in the position of peaks on differential thermogravimetry and differential scanning calorimetry curves of heat-treated samples was observed, indicating changes in the structure of wood polymers. The temperature of heat treatment had a stronger effect on the chemical composition of rubberwood than duration. Significant changes in the chemical composition of rubberwood occurred after the treatment duration of 15 h at both 180 °C and 220 °C. The duration of 25 h and 35 h had no further substantial effect. The isoconversional method of Flynn-Wall-Ozawa was used to determine the kinetics of thermal degradation of untreated and heat-treated rubberwood. It is found that the average values of activation energy in the conversion degree range of 0,05 - 0,65 (the thermal degradation of polysaccharides) increased with increasing treatment temperature and duration. Fourier transform infrared spectra demonstrated alterations in wood polymers.

Theoretical and experimental study on efficient thorium removal from aquatic environment using phosphate-modified graphene oxide polymeric beads

AbstractThorium is an element of immense importance in nuclear industry due to lower environmental impact compared to fossil fuels and conventional nuclear power. In the present study, highly selective adsorption of Th4+ on phosphate modified graphene oxide polymeric beads was investigated. The interaction of –PO4, –OH and –O– functional groups of graphene oxide with thorium ion was thoroughly investigated using Density Functional Theory. The adsorption induced density difference was utilized to investigate the bonding characteristics. The affinity of the Th4+ ions was obtained as –PO4 > –OH > –O– group of the phosphate modified graphene oxide. Phosphate modified Graphene oxide embedded in Calcium alginate matrix was characterized using ATR-FTIR, XRD, SEM and Raman spectroscopy. Highly efficient (> 93%) uptake of thorium at pH 5 with fast rate of sorption (< 5 min) was observed in the batch sorption studies.

Preparation of phosphorous ionic liquids and its effect on the properties of ABS

AbstractTo improve the thermal conductivity and mechanical properties of graphene‐acrylonitrile butadiene‐styrene plastic (ABS) composite, sub‐phosphite‐based ionic liquid (IL) was synthesized, and its structure was characterized by FTIR, NMR, and mass spectrometry. IL was as a modifier, and graphite powder (G powder) was modified by the ball milling method to obtain functional graphene thermal conductive filler (G‐IL). The structure and morphology of G‐IL were characterized by FTIR, X‐ray photoelectron spectroscopy (XPS), XRD, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results of the Molau test showed that the presence of IL improved the interfacial interaction of G‐IL and ABS, enhanced the dispersion of G‐IL in the ABS matrix, made G‐IL contact with each other, and it was easier to establish a thermal conduction network and promote phonon transfer. The thermal conductivity of 9 wt% G‐IL/ABS composite was 0.392 W·m−1·k−1, which was 96% and 14% higher than that of pure ABS and G/ABS composite, respectively. The tensile strength and bending modulus of 9 wt% G‐IL/ABS composite were 44.89 and 2124.37 MPa, which were 13% and 11% higher than those of pure ABS, respectively. The impact strength of 9 wt% G‐IL/ABS composite was 34.17 kJ/m2. It was 18% and 7% higher than that of pure ABS and 9 wt% G‐IL/ABS, respectively.Highlights Phosphorus imidazole ionic liquids were prepared. Graphene was modified by ionic liquids through non‐covalent. Enhanced mechanical properties and thermal conductivity of G‐IL/ABS composites.

Study of Pr doped nanocrystalline LiCoO2 cathode material for spintronic and energy storage applications: A theoretical and experimental analysis

In this study, Pr3+ substituted LiCoO2 lithium-rich cathode materials were prepared using the sol-gel auto-combustion technique to enhance cycling performance. LiCo1-xPrxO2 samples having Pr concentrations x = 0.00–0.10 were synthesized. X-ray diffraction (XRD) showed a rhombohedral structure with space group R-3m, further verified by the Rietveld refinement. Field emission scanning electron microscopy (FESEM) revealed the presence of distinct and well-defined submicron-scale grains. FTIR spectroscopy confirmed Co–O stretching bonds within 590–560 cm−1 and revealed peaks at around 560–590, 830–860, and 1320-1480 cm−1, which could be attributed to the electrochemical performance of Pr-doped species. Moreover, EDX spectroscopy confirmed the typical elemental peaks of only Co, Pr, and O, confirming the required phase presence. The cyclic voltammetry showed improved reversibility and stability due to Pr doping. The first-principles computations were performed using the lattice constant extracted from XRD measurements. The pure LiCoO2 with a semiconducting nature became half-metallic due to Pr doping (LiCo0.84Pr0.16O2). The magnetic properties indicate that LiCoO2 and LiCo0.84Pr0.16O2 exhibit positive magnetic order, which shows that these are suitable candidates for spintronic applications. The pure LiCoO2 revealed intercalation voltages of 4.10–2.73V and a theoretical capacity 40–203 mAh/g. Meanwhile, for LiCo0.84Pr0.16O2, the intercalation voltages and theoretical capacity improved to 4.42–2.85 V and 42 to 211 mAh/g, respectively. The combined experimental and theoretical study suggests that Pr-doped LiCoO2 is suitable for spintronic applications and energy applications such as composite cathodes.

Uncovering novel polyhydroxyalkanoate biosynthesis genes and unique pathway in yeast hanseniaspora valbyensis for sustainable bioplastic production

This study delves into the exploration of polyhydroxyalkanoate (PHA) biosynthesis genes within wild-type yeast strains, spotlighting the exceptional capabilities of isolate DMG-2. Through meticulous screening, DMG-2 emerged as a standout candidate, showcasing vivid red fluorescence indicative of prolific intracellular PHA granules. Characterization via FTIR spectroscopy unveiled a diverse biopolymer composition within DMG-2, featuring distinct functional groups associated with PHA and polyphosphate. Phylogenetic analysis placed DMG-2 within the Hanseniaspora valbyensis NRRL Y-1626 group, highlighting its distinct taxonomic classification. Subsequent investigation into DMG-2’s PHA biosynthesis genes yielded promising outcomes, with successful cloning and efficient PHA accumulation confirmed in transgenic E. coli cells. Protein analysis of ORF1 revealed its involvement in sugar metabolism, supported by its cellular localization and identification of functional motifs. Genomic analysis revealed regulatory elements within ORF1, shedding light on potential splice junctions and transcriptional networks influencing PHA synthesis pathways. Spectroscopic analysis of the biopolymer extracted from transgenic E. coli DMG2-1 provided insights into its co-polymer nature, comprising segments of PHB, PHV, and polyphosphate. GC-MS analysis further elucidated the intricate molecular architecture of the polymer. In conclusion, this study represents a pioneering endeavor in exploring PHA biosynthesis genes within yeast cells, with isolate DMG-2 demonstrating remarkable potential. The findings offer valuable insights for advancing sustainable bioplastic production and hold significant implications for biotechnological applications.

PMMA-Au@YAG:Ce phosphor deposited on flexible substrate for white light emitting devices

This paper investigates the possibility to obtain yttrium aluminum garnet doped with cerium ions (YAG:Ce) phosphor, improve the emissive properties by modification with metal nanoparticles, followed by embedding into the polymer matrix, and deposition of nanocomposite on a flexible substrate to produce the white light by excitation with a blue chip. YAG:Ce yellow phosphor was obtained by a modified solid-state process, followed by in-situ anchoring of gold nanoparticles (Au@YAG). To deposit the phosphor on the flexible substrate, the Au@YAG nanocomposite was embedded in a poly(methyl methacrylate) (PMMA) matrix using the ex-situ method. The quality of the phosphor particles and composites was studied using FTIR spectroscopy, X-ray diffraction, and fluorescence spectroscopy. The applicability of the developed materials and the efficiency of methods were confirmed by the photometric studies performed on the composite film to determine the chromaticity coordinates, leading to the parameters of the semiconductor device that generates cold white light.

Microwave-induced enhancements in the structural, optical, dielectric, and magnetic properties of Er2O3/MgO nanocomposites

Erbium-trioxide (Er2O3) and magnesium oxide (MgO) nanocomposite were effectively synthesized in the form of crystalline powder using a microwave irradiation approach. Various techniques were employed for identifying crystalline structure, FTIR fingerprint region, fluorescence emission behaviors, and surface morphology, dielectric, and magnetic properties using PXRD, FTIR spectroscopy technique, fluorescence spectroscopic technique, SEM analysis, frequency vs. dielectric constant, and MH curve analysis, respectively. Confirmation of the metal-oxygen bond such as Er2O3, and MgO was established through the analysis of stretching frequencies in the FTIR spectrum. The PXRD results using Rietveld refinement confirmed the crystalline nature of the synthesized nanoparticles, consisting of Er2O3, and MgO with unit cell compositions ~ 94.12 and ~ 5.88%, respectively. SEM imaging provided insights into the morphology of the particles, revealing a spherical shape with noticeable agglomeration. The elemental compositions such as Erbium (Er) and Oxygen (O), were validated by the EDS spectrum, confirming the successful achievement of Er2O3, and MgO nanoparticle in the synthesized composite. In addition, the vibrating sample magnetometer (VSM) graph illustrated the paramagnetic behavior of the doped Er2O3/MgO composite at room temperature. The thorough examination of the synthesized Er-MgO NPs, covering structural, morphological, and magnetic characteristics, contributes to a comprehensive understanding of their properties.

Supramolecular Structure of Sulfonamide-Substituted Silatranes: Quantum Chemical DFT Calculations.

The supramolecular structure of the crystal products-N-[2-chloro-2-(silatranyl)ethyl]-4-nitro-benzenesulfonamide 4d and N-chloro-N-[2-chloro-1-(silatran-1-yl-methyl)ethyl]benzene-sulfonamide 5a was established by X-ray diffraction analysis data, FTIR spectroscopy and DFT quantum chemical calculations. Their crystal lattice is formed by cyclic dimers with intermolecular hydrogen NH∙∙∙O-Si bonds and CH∙∙∙O=S short contacts. The distribution of electron density in the monomers was determined using quantum chemical calculations of their molecular electrostatic potential (MESP) in an isolated state (in gas) and in a polar medium. The transition from covalent N-Si bonds in crystal compounds and polar medium to non-covalent N∙∙∙Si bonds happened while performing the calculations on the monomer molecules and their dimers in gas. The effect of intermolecular interactions on the strength of the N-Si and N∙∙∙Si bonds in molecules was evaluated through calculations of their complexes with H2O and DMSO.

Exploring the influence of yttrium on the structural, physical, and optical properties of sol-gel synthesized silicophosphate glasses for photonics applications

Yttrium-incorporated silicophosphate glasses hold significant appeal in key sectors such as photonics, optoelectronics, lasers, biomedical applications, and light-emitting diodes (LEDs). In this study, the sol-gel method has been used to prepare the pure and yttrium-doped silicophosphate glasses. The aim of this study is to discover the effect of yttrium doping on the structural, physical, and optical properties of silicophosphate glasses. Various techniques such as X-ray diffraction (XRD), FTIR spectroscopy, and UV–visible analysis have been employed to examine the structural and optical properties of the prepared samples. The XRD analysis confirmed that all the prepared samples exhibited an amorphous nature. Optical measurements conducted indicated that the incorporation of trivalent yttrium ions led to an increase in the refractive index of the prepared samples. Furthermore, a decrease in the energy band-gap values of the samples was observed. The FTIR spectral analysis unveiled the presence of diverse vibration modes in the synthesized samples. These encompassed symmetrical and asymmetrical stretching vibrations of P-O-P linkages, bending vibrations of P-O in PO4 groups, elongation and flexure vibrations of OH groups, and water absorption vibrations of P-O-H in the glasses. The acquired spectra robustly substantiate the function of yttrium oxide as a network modifier within the silicophosphate glass system. The theoretical values of optical basicity (Λth) demonstrated an increase from 0.465 to 0.472, while the values of the interaction parameter (A) exhibited a decrease from 0.218 Å−3 to 0.215 Å−3. Silicophosphate glasses doped with trivalent yttrium ions exhibit significant potential as materials for optoelectronic devices and optical filter systems.

Anticancer and acute toxicity studies of cellulose-coated Vanadium oxide nanomaterials

In the present research work, a facile hydrothermal method has been used for the preparation of pristine and cellulose-coated Vanadium oxide (V2O5) nanoparticles (NPs). The as-synthesized nanostructures were characterized using XRD, SEM, UV–Vis, PL, DLS, Raman, and FTIR spectroscopy. The crystallite size of the bare V2O5 NPs calculated using XRD analysis was ∼19 nm, which was reduced to ∼16 nm after cellulose functionalization. TEM micrographs revealed the formation of spherical shape NPs with sizes 21 ± 4.9 nm and 16.5 ± 4.4 nm for V2O5 and cellulose – V2O5 respectively. Cellulose-coated Vanadium oxide NPs have shown anticancer potential against the liver cancer cell line (HuH-7.0). Cell viability of V2O5 displayed the IC50 value of 102.182 μg/mL, compared to the coated Vanadium oxide, which was 49.402 μg/mL. In vivo toxicity studies were conducted using healthy albino rats. Pathological parameters indicate acute toxicity due to cellulose-coated Vanadium oxide NPs. The histopathology of cellulose-V2O5 NPs treated livers indicates the swelling in hepatocytes and compressed sinusoidal spaces.

Valorizing sardine scales: a circular approach to sustainable collagen for cosmetics and nutrition applications.

In recent years, the consumption of fish products has led to a worrying trend where approximately two-thirds of the total amount of fish is discarded as waste. At the same time, scientific interest in exploring natural collagen sources for cosmetics and dietary supplements has increased. This study explores the potential of valorizing sardine scales (Sardina pilchardus), a by-product of the canning industry, through the extraction of collagen for potential use in dermocosmetic formulations and food supplements. Collagen from sardine scales was obtained though acid and enzymatic extraction. The collagen extracts were characterized by UV-Vis, FTIR spectroscopy, SDS-PAGE, powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The collagen was hydrolysed with papain to small peptides. Subsequently, the biological activities of acid-soluble collagen as well as the collagen peptides in terms of antioxidant and antimicrobial activity were evaluated. Furthermore, the capacity of collagen peptides to permeate the intestinal barrier, simulated with caco-2 cells, was evaluated. Purified collagen extracts were obtained from sardine scales, with enzymatic extraction method having a yield three times higher than the acid method. The SDS-PAGE analysis confirmed the extraction of type I collagen as well as its hydrolysis into small fragments (25-12kDa). In terms of biological activities, collagen and collagen peptides have not demonstrated antimicrobial activity. However, regarding antioxidant activity, collagen peptides showed three times more capacity compared to non-hydrolyzed collagen. Meanwhile, in 6h, about 6.37% of collagen peptides could permeate the intestinal barrier. This work represents a continuous effort to advance our understanding and utilization of Portuguese marine waste resources, with focus on the valorization of sardine co-products for the development of food supplement or cosmetic formulations, contributing to the sustainable evolution of the circular blue economy.

Determination of antioxidant capacity of glutathione encapsulated in alginate microcapsules using spectrophotometric and electrochemical methods

This paper includes the preparation and physicochemical characterization of sodium alginate microcapsules intended for the oral administration of glutathione (GSH), a vital endogenous antioxidant in combating oxidative stress. Using various methods such as optical microscopy, FTIR spectrometry, and cyclic voltammetry, the morphology, chemical structure, release mechanism, and antioxidant capacity of the released glutathione in simulated digestive fluids (gastric medium with pH=2 and intestinal medium with pH=7.4, without enzymes) were analyzed. The results showed the stability of the alginate microcapsules in digestive fluids and highlighted an increase in encapsulation efficiency with higher concentrations of encapsulated glutathione. Additionally, it was shown that sodium alginate-based microcapsules exhibit different swelling capacities depending on the pH and glutathione concentration, showing remarkable potential for controlled delivery of the active compound. The in vitro release study demonstrated more efficient release of glutathione in simulated intestinal fluid (SIF) than in simulated gastric fluid (SGF). The calculation of the electrochemical index using cyclic voltammetry demonstrated superior antioxidant activity of encapsulated glutathione compared to free glutathione. Correlating the DPPH inhibition percentage with the electrochemical index showed high Pearson coefficients both in SGF and in SIF, indicating a good correlation between DPPH or ABTS free radical species inhibition and electrochemical measurements. Therefore, sodium alginate and glutathione microcapsules show potential for developing efficient delivery systems for glutathione or other pharmaceutical compounds.