FTIR Spectroscopy Research Articles

Investigation of pivalic acid-derived organotin(IV) carboxylates: Synthesis, structural insights, interaction with biomolecules, and computational studies

Herein, six homoleptic and heteroleptic tri-organotin(IV) complexes (1–6) of pivalic acid (HL) were synthesized using 2,2′-bipyridine (bipy) and organotin(IV) chlorides, with a general formula of R3SnL/R3SnLbipy, where R = CH3, C4H9, and C6H5. The structure of the complexes was established in the solid phase via FT-IR spectroscopy and in solution through multinuclear NMR spectroscopy. The variety of coordination modes was implemented by the carboxylate group of pivalic acid, which is reflected in the FT-IR data and also supported by the single crystal XRD analysis for complex 5. The single crystal data revealed the presence of a five-coordinated distorted trigonal bipyramidal geometry for complex 5. The structural and electronic details of the complexes were also evaluated by the application of density functional theory through the Lanl2DZ basis set. The ability of complexes to inhibit the AChE and BChE was assessed in vitro as well as theoretically through molecular docking studies and the results were promising. The complexes 4 and 5 showed high inhibitory potency and could be a potential drug candidate. The DNA binding mode of the complexes was studied using UV–Vis spectroscopy and cyclic voltammetry. The findings revealed that these complexes readily intercalate into DNA via a spontaneous process. Additionally, an effective binding of the complexes with surfactant cetyl trimethyl ammonium bromide (CTAB) through a spontaneous process also proved them valuable in pharmacology.

Synthesis, biological evaluation, molecular docking analyses, and ADMET study of azo derivatives containing 1-naphthol against MβL-producing S. maltophilia

Stenotrophomonas maltophilia is a model organism exhibiting intrinsic antibiotic resistance, primarily due to its production of Mβ-lactamase enzymes that inactivate β-lactam antibiotics. This study aims to synthesize an azo derivative containing an oxazepine ring as a potential inhibitor of Mβ-lactamase. The molecular docking results revealed that the binding energies of the Mβ-lactamases ranged from − 5.95 to − 6.09 kcal/mol, indicating favourable interactions with the synthesized compounds. Two compounds were prepared: the first via aldol condensation of (A1) with p-hydroxybenzaldehyde to form (K1) and the second through Azo-Schiff base formation from 3,5-dimethylaniline, resulting in (L2) and (L18). Characterization of these compounds was conducted via FT-IR, CHN, 1H NMR, and 13C NMR spectroscopy. Antimicrobial activity was assessed through minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) tests, which yielded values ranging from 1.19 ± 1 to 0.02 µg/mL and from 1.12 ± 1 to > 0.04 µg/mL, respectively. Notably, the MBC/MIC ratios indicated that L2 and L18 exhibited significant bactericidal activity. In silico analysis via MOE 2015 software allowed us to determine the binding poses and energies of the synthesized inhibitors against Mβ-lactamase (PDB ID: 6UAF). The most stable conformation from the docking results was selected for further evaluation. Compared with standard ceftazidime, the synthesized compounds significantly inhibited Mβ-lactamase activity. Additionally, ADMET analysis indicated favourable pharmacokinetic profiles and low toxicity, suggesting promising oral drug-like properties for the synthesized molecules.

A novel copper(II) complex with a salicylidene carbohydrazide ligand that promotes oxidative stress and apoptosis in triple negative breast cancer cells.

We report the synthesis, characterization, anti-cancer activity and mechanism of action of a novel water-soluble Cu(II) complex with salicylidene carbohydrazide as the ligand and o-phenanthroline as the co-ligand. The synthesized complex (1) was characterized by FT-IR, EPR, and electronic spectroscopy, as well as single crystal X-ray diffraction. This compound was found to be paramagnetic from EPR spectra and X-ray crystallography revealed that the molecule crystallized in an orthorhombic crystal system. The crystal lattice was asymmetric containing two distinct binuclear copper complexes containing the Schiff base as the major ligand, o-phenanthroline as a co-ligand, two nitrate anions, and two water molecules. The Cu(II) in the first site coordinated with the enolised ligand comprising enolate O-, phenolate O-, and the imine N and N,N from o-phen. The major part of this complex exists as Cu(II) coordinated with two H2O molecules at the second site with nitrate acting as the counter anion. However, a smaller portion of the complex exists where Cu(II) is coordinated with NO3- and H2O, and the remaining water molecule acts as lattice water. It was tested for DNA binding and cleavage properties which revealed that it binds in an intercalative mode to CT-DNA with Kb value of 1.25 × 104 M-1. Furthermore, cleavage studies reveal that the complex has potential for efficient DNA cleavage under both oxidative and hydrolytic conditions. It was able to enhance the rate of cleavage by 2.8 × 108 times. The complex shows good cytotoxicity to breast cancer monolayer (2D) as well as spheroid (3D) systems. The IC50 values for MDA-MB-231 and MCF-7 monolayer culture was calculated as 1.86 ± 0.17 μM and 2.22 ± 0.08 μM, respectively, and in (3D) spheroids of MDA-MB-231 cells, the IC50 value was calculated to be 1.51 ± 0.29 μM. It was observed that the complex outperformed cisplatin in both breast cancer cell lines. The cells treated with complex 1 underwent severe DNA damage, increased oxidative stress and cell cycle arrest which finally led to programmed cell death or apoptosis in triple negative breast cancer cells through an intrinsic pathway.

Electrolyte-Salts Regulated Hydrogen-Bonding Configuration and Interphase Formation Achieving Highly Stable Anode for Rechargeable Aqueous Sodium-Ion Batteries.

Hydrogen evolution reactions that cause the alkalization of aqueous electrolytes generally frustrate the structural stability and cycling performance of NaTi2(PO4)3/C anode material for rechargeable aqueous sodium-ion batteries (ASIBs). Herein, a novel highly concentrated electrolyte with a large hydrogen-evolution overpotential and hydroxide-capture ability is rationally established by incorporating a bifunctional Mg(Ac)2 additive into a concentrated NaAc aqueous solution. The highly concentrated electrolyte salts (4m NaAc+3m Mg(Ac)2) favor regulation on hydrogen-bonding configurations and kinetically shift the hydrogen evolution potential to a lower value of -1.37 V (vs Ag/AgCl). The Mg(Ac)2 additive plays particular roles in spontaneously capturing hydroxide ions generated during hydrogen evolution reactions on anode surfaces and simultaneously forming a protective Mg(OH)2-like interphase. As a result, the unique electrolyte significantly improves the structural stability and cycling performance of NaTi2(PO4)3/C anode (94.8% capacity retention after 100 cycles at 100 mA·g-1). The effect of salt concentration on hydrogen bonding configurations of aqueous electrolytes is investigated with Raman spectroscopy and FTIR spectroscopy. The interphase is identified by coupling EDS mapping, X-ray photoelectron spectroscopy, and X-ray diffraction. This work provides a new strategy for improving the cycling stability of aqueous sodium-ion batteries.

Biomimetic Cooling: Functionalizing Biodegradable Chitosan Films with Saharan Silver Ant Microstructures.

The increasing occurrence of hot summer days causes stress to both humans and animals, particularly in urban areas where temperatures can remain high, even at night. Living nature offers potential solutions that require minimal energy and material costs. For instance, the Saharan silver ant (Cataglyphis bombycina) can endure the desert heat by means of passive radiative cooling induced by its triangular hairs. The objective of this study is to transfer the passive radiative cooling properties of the micro- and nanostructured chitin hairs of the silver ant body to technically usable, biodegradable and bio-based materials. The potential large-scale transfer of radiative cooling properties, for example, onto building exteriors such as house facades, could decrease the need for conventional cooling and, therefore, lower the energy demand. Chitosan, a chemically altered form of chitin, has a range of medical uses but can also be processed into a paper-like film. The procedure consists of dissolving chitosan in diluted acetic acid and uniformly distributing it on a flat surface. A functional structure can then be imprinted onto this film while it is drying. This study reports the successful transfer of the microstructure-based structural colors of a compact disc (CD) onto the film. Similarly, a polyvinyl siloxane imprint of the silver ant body shall make it possible to transfer cooling functionality to technically relevant surfaces. FTIR spectroscopy measurements of the reflectance of flat and structured chitosan films allow for a qualitative assessment of the infrared emissivity. A minor decrease in reflectance in a relevant wavelength range gives an indication that it is feasible to increase the emissivity and, therefore, decrease the surface temperature purely through surface-induced functionalities.

Hybrid composite beads of chitosan/graphene oxide for dye adsorption: characterizations, kinetic modeling and toxicity study

The current study aimed to the preparation of graphene oxide impregnated chitosan– polyvinyl alcohol hybrid beads (GO/CS-PVA) for the removal of Reactive Black 5 (RB5) dye from wastewater solutions, presenting them as a cost-effective alternative for wastewater treatment. These hybrid beads were fabricated using a dripping technique in an aqueous solution. The surface and structure of the material before and after adsorption process were studied by analyzing FTIR spectroscopy and Scanning electron microscope (SEM) as well as adsorption capacity was also evaluated. The results proved the successful synthesis of GO/CS-PVA beads and elucidated the physical adsorption mechanism of RB5. SEM images revealed uniform spherical beads with a rough surface, approximately 752 μm in diameter. Additionally, the evaluation of adsorption capacity showed that the optimum condition for RB5 adsorption is at pH = 3 while the kinetic investigations revealed that the adsorption process adhered to the pseudo-second-order model, indicating a chemisorption reaction. Furthermore, an increase in temperature from 25 to 65 °C enhanced the maximum adsorption capacity of GO/CS-PVA beads by 34%. The cytotoxic effect of the hybrid as measured on adipose derived stem cells via the MTT assay was negligible. In conclusion, it was proved that the eco-friendly GO/CS-PVA beads adsorbents can efficiently remove RB5 from wastewater in practical applications.

Advanced Nuclear Magnetic Resonance, Fourier Transform–Infrared, Visible-NearInfrared and X-ray Diffraction Methods Used for Characterization of Organo-Mineral Fertilizers Based on Biosolids

Biosolids from stabilized sludge present a high fertilization potential, due to their rich content of nutrients and organic matter. The intrinsic and subtle properties of such fertilizers may greatly influence the fertilization efficiency. In this sense, the utility, advantages and limitations of advanced characterization methods, for the investigation of structural and dynamic properties at the microscopic scale of slightly different formulations of fertilizers were assessed. For that, three formulas of organo-mineral fertilizers based on biosolids (V1, V2 and V3), having at least 2% N, 2% P2O5, and 2% K2O, were characterized by advanced methods, such as 1H NMR relaxometry, 1H MAS and 13C CP-MAS NMR spectroscopy, 1H double-quantum NMR and FT-IR spectroscopy. Advanced structural characterization was performed using SEM, EDX and X-ray diffraction. Four dynamical components were identified in the NMR T2 distribution showing that the rigid component has a percentage larger than 90%, which explains the broad band of NMR spectra confirmed by the distributions of many components in residual dipolar coupling as were revealed by 1H DQ-NMR measurements. SEM and EDX measurements helped the identification of components from crystalline-like X-ray diffraction patterns. To evaluate the release properties of organo-mineral fertilizers, dynamic measurements of classical electric conductivity and pH were performed by placing 0.25 g of the formulas (V1, V2 and V3) in 200 mL of distilled water. The content of N and P were quantified using specific reactants, combined with VIS-nearIR spectroscopy. Two release mechanisms were observed and characterized. It was found that V3 presents the smallest release velocity but releases the largest number of fertilizers.

Exploring the potential of SnSe/PANi composite counter electrodes for improved efficiency in dye-sensitized solar cells

This paper investigates the synthesis and characterization of novel counter electrodes (CEs) for dye-sensitized solar cells (DSSCs), focusing on composite polyaniline (PANi) nanofibers integrated with tin selenide (SnSe). Three CEs, namely SnSe, PANi, and their composite, were prepared via facile hydrothermal and cyclic voltammetry methods and compared with a standard platinum (Pt) CE. The efficiencies obtained were 4.20 %, 5.63 %, 8.39 %, and 7.72 % for SnSe, PANi, SnSe/PANi, and Pt CEs, respectively. The improved efficiencies, particularly in the case of the SnSe/PANi composite, were attributed to increased short-circuit density of the composite sample. The materials and devices prepared in this study are characterized using various methods including FESEM, TEM, XRD, Raman and FTIR spectroscopies, EIS, Tafel, OCVD, IPCE and etc to support our proposed CE structure. Our findings demonstrate the promising potential of SnSe/PANi composite CEs in enhancing the performance and affordability of DSSCs.

Polyacrylonitrile Ultrafiltration Membrane for Separation of Used Engine Oil

The separation of used engine oil (UEO) with an ultrafiltration (UF) membrane made of commercial copolymer of poly(acrylonitrile-co-methyl acrylate) (P(AN-co-MA)) has been investigated. The P(AN-co-MA) sample was characterized by using FTIR spectroscopy, 13C NMR spectroscopy, and XRD. The UF membrane with a mean pore size of 23 nm was fabricated by using of non-solvent-induced phase separation method—the casting solution of 13 wt.% P(AN-co-MA) in dimethylsulfoxide (DMSO) was precipitated in the water bath. Before the experiment, the used engine oil was diluted with toluene, and the resulting UEO solution in toluene (100 g/L) was filtered through the UF membrane in the dead-end filtration mode. Special attention was given to the evaluation of membrane fouling; for instance, the permeability of UEO solution was dropped from its initial value of 2.90 L/(m2·h·bar) and then leveled off at 0.75 L/(m2·h·bar). However, the membrane cleaning (washing with toluene) allowed a recovery of 79% of the initial pure toluene flux (flux recovery ratio), indicating quite attractive membrane resistance toward irreversible fouling with engine oil components. The analysis of the feed, retentate, and permeate by various analytical methods showed that the filtration through the UF membrane made of P(AN-co-MA) provided the removal of major contaminants of used engine oil including polymerization products and metals (rejection—96.3%).

Ferrocenyl Dithiophosphonate Ag(I) Complexes: Synthesis, Structures, Luminescence, and Electrocatalytic Water Splitting Tuned by Nuclearity and Ligands.

The heterometallic [Ag(I)/Fe(II)] molecular electrocatalysts for hydrogen production were introduced here to recognize the mutual role of metallic nuclearity and ligand engineering. A series of ferrocenyl dithiophosphonate stabilized mononuclear [Ag(PPh3)2{S2PFc(OR)}] {where R=Me (1), Et (2), nPr (3), iPr (4), iAmyl (5); Fc=Fe (ɳ5-C5H4) (ɳ5-C5H5)} and dinuclear [Ag(PPh3){S2PFc(OR}]2 {where R=Et (2 a), and nPr (3 a)} complexes were synthesized and characterized by SCXRD, NMR (31P and 1H), ESI-MS, UV-Vis, and FT-IR spectroscopy. The comparative electrocatalytic HER behavior of 1-5 and 2 a-3 a showed effective current density of 1 mA/cm2 with overpotentials ranging from 772 to 991 mV, demonstrating the influence of extended and branched carbon chains in dithiophosphonates and metallic (mono-/di-) nuclearity, which correlates with documented tetra-nuclear [Ag4(S2PFc(OnPr)4], 6. DFT study suggests the coordinated (μ1-S) site of ligands is the reactivity center and the adsorption energy of intermediate [H*-SM] varies with the engineering of ligand and nuclearity. A catalytic mechanism using mononuclear (1) and di-nuclear (2 a) was proposed with the assistance of DFT. Each complex, being the first example of Ag(I) dithiophosphonates, exhibits intense photoluminescence with high quantum yields ranging from 33 % to 67 %. These results link the lower nuclearity structures to their physical and catalytic properties.

Chemical Synthesis and Characterization of Fatty Acid-Capped ZnO Nanoparticles

In the current study, ZnO nanoparticles were obtained using a chemical process employing zinc acetate as the precursor, followed by thermal processing in air. To prevent agglomeration and increase the stability of ZnO nanoparticles, two unsaturated acids (e.g., elaidic acid and linoleic acid) and two saturated acids (e.g., stearic acid and lauric acid) were selected as capping agents. ZnO nanoparticles were investigated before and after surface modification with different fatty acids. Structural and morphological analyses of the samples were performed using FTIR and RAMAN spectroscopy, X-ray diffraction, SEM microscopy, and wetting capacity. Characterization studies revealed that the synthesized ZnO nanoparticles present well-defined crystalline structures, with crystallite sizes varying between 26 and 28 nm, and the average particle size was in the range of 10–55 nm (depending on the type of fatty acids used). The goniometric analysis followed the wetting capacity of the sample surface. The study results reveal that the capping agents have a considerable impact on the surface modification of the nanoparticles by increasing the contact angle. By producing nanoparticles with hydrophobic behavior, there is the possibility of opening up future research for their use in various applications across many industrial fields.

Influence of Pyridine Entangled Novel Hybrid Quinoxaline Spirane on the Fluorescence and Absorption Spectra of Biomolecules: Molecular Docking, Pharmacokinetic, and In-Vitro Biological Investigations.

Spectroanalytical techniques are extensively employed in contemporary research to characterize compounds and assess their biological activity. The β-lactam ring containing twenty novel spiro quinoxaline-pyridine heterocyclic compounds (A - T) were synthesized and characterized using 1H NMR, 13C NMR, FT-IR, and mass spectrometry. The compounds must interact with DNA to adequately assess their potential anticancer action. Thus, their binding affinities with calf-thymus (CT) DNA and bovine serum albumin (BSA) were evaluated using a UV-visible spectrophotometer. The Kb value of compound-DNA and compound-BSA was found in the order of 0.51-2.53 M- 1 and 0.11-2.03 M- 1, respectively. Furthermore, a fluorescence quenching study was also carried out using a fluorescence spectrometer to explore DNA/BSA binding, and a partial intercalation type of binding was suggested. MTT assay was performed to evaluate the anticancer activity of the compounds. A docking study of all the compounds was performed with DNA (1 BNA), BSA (4F5S), and topoisomerase II (3QX3) using autodock vina software. SwissADME and admetSAR, two online platforms, were used to assess the pharmacokinetic profile and determine the drug-likeness of the synthesized compounds.

The Trifluorooxygenate Anion [OF3]-: Spectroscopic Evidence for a Binary, Hypervalent Oxygen Species.

Experimental evidence for hypervalent compounds of second-row elements is still scarce in literature. Here, we present the first report of the long-sought binary hypervalent trifluorooxygenate anion [OF3]-. It was isolated in solid Ne matrices under cryogenic conditions after reacting oxygen difluoride with free fluoride ions from laser ablation of alkali metal fluorides MF (M = Li-Cs). As predicted by VSEPR theory and calculations at the CCSD(T) level, and confirmed by FTIR spectroscopy as well as isotopic labeling, [OF3]- exhibits a C2v-symmetric T-shaped structure with one short and two long O-F bond distances. Analysis of the natural local molecular orbitals shows the presence of 2c-2e bond and one 3c-4e bond. Natural resonance theory indicates the importance of the stability of [OF2]•- for the stability of [OF3]-. Although free [OF2]•- was not detected, the species MOF2 (M = Na-Cs) could be observed in the same experiments, which are best described as contact ion pairs of M+[OF2]•-.

Thermal Decomposition of 2-Cyclopentenone.

The thermal decomposition of 2-cyclopentenone, a cyclic oxygenated hydrocarbon that occurs in the pyrolysis of biomass, has been studied in a combined experimental and theoretical approach. Gas-phase pyrolysis was performed at temperatures ranging from 1000 to 1400 K in a pulsed, microtubular reactor. Products were identified by FTIR spectroscopy following their isolation in a low-temperature argon matrix. The following products were identified: carbon monoxide, ketene, propenylketene, vinylacetylene, ethylene, propene, acrolein, acetylene, propyne, and propargyl radical. Computational results identify three different decomposition channels involving a H atom migration, and producing prop-2-enylketene (Pathway 1), prop-1-enylketene (Pathway 2), and a second conformation of prop-2-enylketene (Pathway 3). A fourth decomposition pathway involves simultaneous rupture of two C-C bonds forming a high energy cyclopropenone intermediate that further reacts to form ethylene, acetylene, and carbon monoxide. Finally, a fifth pathway to the formation of acrolein and acetylene was identified that proceeds via a multistep mechanism, and an interconversion from 2-cyclopentenone to 3-cyclopentenone was identified computationally, but not observed experimentally.

Enhancing Herbal Efficacy: Synthesis and Evaluation of Nanosuspension from Withania somnifera Root Extract

Background: Ayurveda emphasizes the balance of mind, body, and spirit, drawing on ancient texts that highlight the medicinal properties of herbs like Withania somnifera, known for its wide range of therapeutic applications and pharmacological benefits. Commonly referred to as Indian ginseng or Ashwagandha, Withania somnifera, demonstrates a variety of therapeutic effect , including anti-inflammatory, antitumor, sedative, hypnotic, deobstruent effects, narcotic, antioxidant, tonic, antistress, diuretic, aphrodisiac, immunomodulatory, and rejuvenating properties. Nanotechnology, particularly through the development of nanosuspensions, offers a significant advancement in medicine, addressing challenges like poor solubility and low bioavailability of lipophilic drugs. Nanosuspensions can enhance drug safety and efficacy by improving solubility and altering pharmacokinetics. Methods: This study focuses on formulating and characterizing a nanosuspension using an ethanolic extract of Withania somnifera roots. The nanosuspension (NSWS) underwent comprehensive characterization, utilizing techniques such as FT-IR spectroscopy, particle size analysis, zeta potential measurement, polydispersity index (PDI) assessment, Field emission scanning electron microscopy (FESEM), X-ray diffraction analysis, pH measurement, and stability testing. This study seeks to explore the potential of nanosuspensions, aiming to integrate nanotechnology with herbal medicine to improve the safety and efficacy of herbal formulations. Results: The nanosuspension (NSWS) shown particle size about 133.09 nm, and its uniform particle distribution was indicated by a Polydispersity Index (PDI) about 0.27. Stability and uniformity were further supported by the zeta potential, particle size, and PDI values. Conclusion: Nanosuspension formulations represents a versatile strategy to improve the therapeutic efficacy of hydrophobic drugs across various routes of administration. Keywords: Withania somnifera, Nanosuspension, Characterization, FT-IR, PDI, FESEM

Robust Self-Healing Adhesives Based on Dynamic Urethane Exchange Reactions.

Thermoset polyurethanes (PUs) have been successfully reprocessed as covalent adaptable networks (CANs) by catalyzing carbamate exchange. Here we extend bond exchange beyond the internal network cross-links to create a dynamic urethane adhesive. Interfacing PU CANs to substrates with nucleophilic functional groups creates adhesives capable of reversible transcarbamoylation with the substrate, which has not been demonstrated previously by CAN adhesives. Two types of thermoset PU films were synthesized, one containing the green carbamate exchange catalyst Zr(tmhd)4 and the other containing no catalyst. Although otherwise identical in chemical and network properties, as indicated by FT-IR spectroscopy and dynamic mechanical thermal analysis (DMTA), the film containing catalyst showed dynamic bond exchange behavior through stress relaxation analysis. When evaluated as an adhesive, the CAN film exhibited self-healing properties and retained its adhesive strength for five cycles, which is attributed to reversible covalent bonding to the glass substrate. This work expands industrially relevant CANs to structural adhesives and demonstrates their potential value in an application that presently employs PUs as single-use materials.

The Trifluorooxygenate Anion [OF3]−: Spectroscopic Evidence for a Binary, Hypervalent Oxygen Species

Experimental evidence for hypervalent compounds of second‐row elements is still scarce in literature. Here, we present the first report of the long‐sought binary hypervalent trifluorooxygenate anion [OF3]−. It was isolated in solid Ne matrices under cryogenic conditions after reacting oxygen difluoride with free fluoride ions from laser ablation of alkali metal fluorides MF (M = Li–Cs). As predicted by VSEPR theory and calculations at the CCSD(T) level, and confirmed by FTIR spectroscopy as well as isotopic labeling, [OF3]− exhibits a C2v‐symmetric T‐shaped structure with one short and two long O‐F bond distances. Analysis of the natural local molecular orbitals shows the presence of 2c‐2e bond and one 3c‐4e bond. Natural resonance theory indicates the importance of the stability of [OF2]•− for the stability of [OF3]−. Although free [OF2]•− was not detected, the species MOF2 (M = Na–Cs) could be observed in the same experiments, which are best described as contact ion pairs of M+[OF2]•−.

Gold Nanoparticle-Embedded Thiol-Functionalized Ti3C2Tx MXene for Sensitive Electrochemical Sensing of Ciprofloxacin.

The unregulated use of ciprofloxacin (CIPF) has led to increased resistance in patients and has threatened human health with issues such as digestive disorders, kidney disorders, and liver complications. In order to overcome these concerns, this work introduces a portable electrochemical sensor based on a disposable integrated screen-printed carbon electrode (SPCE) coated with gold nanoparticle-embedded thiol-functionalized Ti3C2Tx MXene (AuNPs-S-Ti3C2Tx MXene) for simple, rapid, precise, and sensitive quantification of CIPF in milk and water samples. The high surface area and electrical conductivity of AuNPs are maximized thanks to the strong interaction between AuNPs and SH-Ti3C2Tx MXene, which can prevent the aggregation of AuNPs and endow larger electroactive areas. Ti3C2Tx MXene was synthesized from Ti3AlC2 MAX phases, and its thiol functionalization was achieved using 3-mercaptopropyl trimethoxysilane. The prepared AuNPs-S-Ti3C2Tx MXene nanocomposite was characterized using FESEM, EDS, XRD, XPS, FTIR, and UV-visible spectroscopy. The electrochemical behavior of the nanocomposite was examined using CV, EIS, DPV, and LSV. The AuNPs-S-Ti3C2Tx MXene/SPCE showed higher electrochemical performances towards CIPF oxidation than a conventional AuNPs-Ti3C2Tx MXene/SPCE. Under the optimized DPV and LSV conditions, the developed nonenzymatic CIPF sensor displayed a wide range of detection concentrations from 0.50 to 143 μM (DPV) and from 0.99 to 206 μM (LSV) with low detection limits of 0.124 μM (DPV) and 0.171 μM (LSV), and high sensitivities of 0.0863 μA/μM (DPV) and 0.2182 μA/μM (LSV).

Removal of the nalidixic acid antibiotic from aqueous solutions using bovine serum albumin nanoparticles

The presence of antibiotic pollutants in water and wastewater can cause significant risks to the environment in different aspects. Therefore, antibiotics need to be removed from water. This study investigates the adsorption of nalidixic acid (NA), a common antibiotic, using bovine serum albumin nanoparticles (BSA NPs). These NPs were synthesized via desolvation technique and characterized using SEM, DLS, FT-IR, and UV-Vis spectroscopy. The effects of adsorbent dosage (0.02–0.9 mg), initial NA concentration (30–80 mg L− 1) and contact time (0.5–24 h) on adsorption efficiency were considered. Adsorption isotherms and kinetics were determined experimentally. The Freundlich isotherm best described the adsorption equilibrium, while the pseudo-second-order kinetic model accurately represented the adsorption process. Thermodynamic parameters confirmed the spontaneous and exothermic nature of NA adsorption onto BSA NPs. Under optimal conditions, BSA NPs achieved a removal efficiency of 75% for NA with a maximum adsorption capacity of 240 mg g− 1. These results demonstrate the potential of BSA NPs as an effective adsorbent for removing NA from aqueous solutions.

Novel Zn(II), Co(II) and Cu(II) diflunisalato complexes with neocuproine and their exceptional antiproliferative activity against cancer cell lines.

Three novel complexes of deprotonated diflunisal (dif) with neocuproine (neo) were synthesized and characterized via elemental, spectral (UV-vis, FTIR, fluorescence, and mass spectrometry), and single-crystal X-ray diffraction analyses. Although the compounds shared a similar composition of [MCl(dif)(neo)], where M represents Zn(II) (1), Co(II) (2) and Cu(II) (3), only 1 and 2 were isostructural, while 3 differed in both the molecular and supramolecular structures. In all three complex molecules, the central atom is coordinated by two nitrogen atoms of neo in a bidentate chelate mode, and one chlorido ligand and dif is bonded in either a monodentate mode via one oxygen atom of the carboxylate in 1 and 2 or in a bidentate chelate mode via both carboxylate oxygen atoms in 3. All three compounds demonstrated remarkable antiproliferative activity against human prostate (PC-3), colon (HCT116) and breast (MDA-MB-468) cancer cell lines with IC50 values in the nanomolar range, with the lowest values observed in the case of PC-3 and MDA-MB-468 with 2 (20.0 nM) and 3 (31.1 nM), respectively. Moreover, complex 2, as the most active, was further investigated for its potential to induce perturbations in the cell cycle of PC-3 cells. The results indicated an induction of caspase-independent apoptosis. The interaction of the complexes with genomic DNA isolated from the respective cancer cell lines was evaluated for the intercalative mode, with binding strength correlated with the antiproliferative activity against PC-3 and MDA-MB-468 cancer cell lines.