Shift Of Absorption Band Research Articles

A structural and optical modification of ZnO-Fe2O3 nanocomposite for enhancing catalytic activity

This study investigates the photocatalytic degradation of organic Methyl Blue (MB) using a ZnO-Fe2O3 composite prepared via the sol-gel technique. FTIR analysis elucidates the substantial impact of Fe2O3 addition, as evidenced by shifts in the ZnO absorption bands, notably observed at 631 cm-1 and 919.74 cm-1 peaks. X-ray diffraction (XRD) corroborates heightened crystallinity due to interactions between ZnO and Fe2O3. SEM analysis unveils a highly aggregated structure, showcasing promising capabilities for efficient dye degradation and environmental applications. Photoluminescence (PL) spectra exhibit an intensified peak at 377 nm, indicative of efficient charge separation and electron transfer, offering potential in optoelectronic applications. The composite's distinctive refractive index (n) of 2.33, extinction coefficient (k) of 2.12, optical electronegativity (∆X*) of 0.75, and dielectric constants (εr of 0.40 and εi of 9.92) underscore its versatile bonding and broad application prospects. Evaluating the photocatalytic activity (PCA) reveals that among all samples, the nanocomposite ZnO-Fe2O3 synthesized at 500°C exhibits superior performance, showcasing heightened degradation of MB dye under 90 minutes of sunlight irradiation.

Observation at radio frequencies of the hydroxyl (OH) absorption line in filaments and prominences above active regions of the Sun

When observing the Sun with RATAN-600 radio telescope using a spectropolarimetric complex in the range 1–3 GHz, as well as when observing coronal rain, absorption in the radio emission was discovered in the spectral region 1.5–1.65 GHz in active solar regions located under a cold filament or on the limb under a prominence. The observed line structure corresponds to the hyperfine splitting frequencies in the ground state of X2Π3/2 hydroxyl (OH) 1612–1720 MHz. When the observed active region passes through the knife-shaped beam pattern of the telescope antenna, the absorption band shifts in frequency due to a shift in the energy levels of the OH molecule in a magnetic field, which changes along the filament.

Наблюдение в радиодиапазоне линии поглощения гидроксила (ОН) в волокнах и протуберанцах над активными областями Солнца

When observing the Sun with RATAN-600 radio telescope using a spectropolarimetric complex in the range 1–3 GHz, as well as when observing coronal rain, absorption in the radio emission was discovered in the spectral region 1.5–1.65 GHz in active solar regions located under a cold filament or on the limb under a prominence. The observed line structure corresponds to the hyperfine splitting frequencies in the ground state of X2Π3/2 hydroxyl (OH) 1612–1720 MHz. When the observed active region passes through the knife-shaped beam pattern of the telescope antenna, the absorption band shifts in frequency due to a shift in the energy levels of the OH molecule in a magnetic field, which changes along the filament.

Sorption-spectrophotometric determination of bismuth ion (III) using immobilised xylenol orange on modified polyacrylonitrile

ABSTRACT This study presents a new sorption-spectrophotometric method for determining bismuth (III) ions using a new adsorbent for PPM-1 fibre immobilised with xylenol orange. The complex exhibited a maximum reflectance at 550 nm and absorption at 530 nm, indicating stable formation. The method demonstrated high sensitivity with a detection limit of 0.1 µg/mL and high selectivity, minimising interference from other metal ions. Optimal pH for complex formation was 1.37, with faster response and higher sensitivity in the immobilised state (detection limit 0.12 µg/mL, formation time 10 minutes). The complex adhered to the Bouguer-Lambert-Beer law within 3–42 µg/25 mL. Interferences from Cu2+, Ag+, Pd2+, and Fe3+ were reduced when the reagent was immobilised. Conductometric analysis confirmed the stable formation of the complex. Validation using model mixtures and pharmaceutical preparations showed accurate bismuth determination with an error margin of 0.005. For example, a mixture containing 25 µg of bismuth with zinc and cadmium yielded 25.20 µg, and De-nol had a found content of 49.50 µg for 50.00 µg added. IR spectroscopy confirmed complex formation with significant shifts in absorption bands. SEM and EDS analysis validated the reagent’s effective immobilisation and interaction with bismuth ions. The method provides a rapid, accurate, and environmentally friendly approach for bismuth analysis, demonstrating high reproducibility, sensitivity, and selectivity, suitable for environmental monitoring and pharmaceutical quality control.

Perylene-3,4,9,10-tetracarboxylic dianhydride dye intercalated liquid crystal molecules: Synthesis, spectroscopic characterizations and photoluminescence dynamics

The present research explores the interaction between perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA)-dye (PD) and 3b {(E)-1-[3-fluoro-4-(pentyloxy)phenyl]-2-(4-methylphenyl)diazene} liquid crystal (LC) mesophase, 3c{(E)-1-[3-fluoro-4-(hexyloxy)phenyl]-2-(4-methylphenyl)diazene} nematic liquid crystal (NLC) molecule. Spectroscopic characterizations of 3b@PD LC mesophase and 3c@PD NLC molecule were carried out using scanning electron microscopy (SEM), polarizing optical microscope (POM), Raman, Fourier transform infrared spectroscopy (FT-IR), and UV–visible analytical methods. The UV–visible studies revealed a red shift in absorption bands (348.0 nm to 374 nm) with a decrease in optical band gap from 2.43 eV to 2.25 eV. Room temperature photoluminescence (RTPL) spectra of 3b@PD LC mesophase exhibited blue light emission characteristics centred at 453.1 nm and 3c @PD NLC molecule showed broad emission peaks located at 400.7 nm and 324.8 nm. Steady-state photoluminescence (SSPL) spectra showcased indigo-purple emission bands corresponding to the wavelengths 303–353 nm, 420.5 nm, 418 nm, 418.3 nm, and 347.0 nm, however, for the 3c@PD NLC molecule, emission intensity peaks appeared at 429.6 nm, 418.0 nm and 329.0 nm. The stoke’s shift for 3b@PD LC mesophase varied between 0.01 eV to 0.613 eV while for 3c@PD NLC molecule it was found in between 0.317 eV to 0.453 eV. POM analysis unveiled distinct fan-like textures with varied colour interfaces. Time-resolved photoluminescence (TRPL) decay studies unveiled average lifetime of 3b@PD LC mesophase was 1.80 ns, 0.98 ns, 0.308 ns and for 3c@PD NLC molecule, the average lifetime was found to be 0.98 ns, 0.82 ns, and 0.306 ns at various excitation wavelengths. However, phosphorescence decay studies showed faster decay characteristics for 3c@PD NLC molecule (1.40 ns to 4.00 ns) compared with 3b@PD LC mesophase (1.65 to 5.42 ns) when excited at various wavelengths. The interaction between LC molecules and PTCDA demonstrated a significant enhancement in RTPL, TRPL, and SSPL properties, suggesting promising applications in photonics and optoelectronics.

Germanium Single Crystals for Photonics

Germanium (Ge) is a system-forming material of IR photonics for the atmospheric transparency window of 8–14 µm. For optics of the 3–5 µm range, more widespread silicon (Si), which has phonon absorption bands in the long-wave region, is predominantly used. A technology for growing Ge single crystals has been developed, allowing the production of precision optical parts up to 500 mm in diameter. Ge is used primarily for the production of transparent optical parts for thermal imaging devices in the 8–14 µm range. In addition, germanium components are widely used in a large number of optical devices where such properties as mechanical strength, good thermal properties, and climatic resistance are required. A very important area of application of germanium is nonlinear optics, primarily acousto-optics. The influence of doping impurities and temperature on the absorption of IR radiation in germanium is considered in detail. The properties of germanium photodetectors are reported, primarily on the effect of photon drag of holes. Optical properties in the THz range are considered. The features of optical properties for all five stable isotopes of germanium are studied. The isotopic shift of absorption bands in the IR region, caused by phonon phenomena, which was discovered by the authors for the first time, is considered.

Features of spectral characteristics of phenyl-containing vanadium (III) β-diketonates

Tris-dibenzoylmethanate ([V(dbm)3 ]) and tris-benzoylacetonate vanadium ([V(bac)3 ]) were obtained by electrochemical synthesis. The composition of chelates was determined using elemental analysis and IR spectral data. It was shown that the formation of a quasi-aromatic metallocycle, the main structural element of chelate, occurred as a result of electrolysis. At the same time, the batachromic shift of absorption bands of carbonyl groups was more than 100 cm–1. The overwhelming majority of absorption bands in the IR spectra of both compounds had mixed nature. For ([V(dbm)3 ] the characteristic of absorption bands did not exceed 13.5 %, and for [V(bac)3 ] – 10.3 %. The peripheral groups of ligands (phenyl and methyl) did not undergo transformation when influenced by electric current.

Structure-optical properties of CdO glass matrix with low levels of cobalt impurities

The impacted role of cadmium oxide (CdO) on the structure-optical properties of current borate glasses with low cobalt oxide impurities was studied. The study was performed on a glass system of the formula [x CdO – (80-x) B2O3 – 0.4 CoO – 19.6 Na2O]; x = 0, 6, 12, 18 and 24 mol%, and produced by melt quenching method. Structure and optical absorption spectroscopy were done to explore the electronic transitions of Co cations inside the glass matrix. The obtained data indicated that structure and optical properties were significantly changed following CdO additives. Bands of optical absorption within both visible and near-infrared ranges showed signatures from Co2+ cations in the tetrahedral and octahedral sites, while Co3+ cations in the octahedral sites within the glass network. Optical absorption also changed significantly for the CdO-doped glasses which exhibited red shifts in visible absorption bands and blue shifts in the NIR absorption bands. The obtained absorption bands in both visible and NIR were employed to obtain the crystal field splitting parameter (Δt) showing augmented records from 3364 cm−1 to 3377 cm−1 with more CdO addition. The Tauc gap energy values were then attained showing decreased values from 3.50 to 3.27 eV when further CdO is added. Further, the impacted role of CdO addition on the nonlinearity optical properties of the present glasses was finally estimated. Potential increases in the linear and nonlinear optical are discussed based on polarizability and basicity increments inside the glass matrix.

Impact of SnO2 doping on spectroscopic characteristics of the SnO2-Na2O-CoO-B2O3 borate glass matrix

The role of tin oxide (SnO2) on the structure-optical features of borate glasses containing low cobalt oxide impurities was studied. The study was carried out on a glass system [x SnO2 – (80-x) B2O3 – 19.5 Na2O – 0.5 CoO]; x = 0.0, 0.5, 1.0, 2.0 and 3.0 mol%. Glass synthesis was carried out by the melt-quench technique. Structure and optical absorption spectroscopy were carried out to explore the optical transitions of Co cations inside the present glass matrix. The obtained results indicate that, with the further addition of SnO2 content, the molar volume decreased from 31.675 cm3/mol to 29.147 cm3/mol. FTIR studies indicated the basic structural units of trigonal BO3 units and BO4 tetrahedra. Herein also, additional contents of tin oxide increased the nonbridging oxygen contents. The reason behind such increment is attributed to the existence of Sn4+ ions in octahedral coordination acting as network modifiers. Optical absorption spectra indicated the existence of Co ions in both Co2+ and Co3+ oxidation states. Moreover, the existence of significant SnO2 concurred with the significant blue shift in the visible absorption bands and red shift in near infrared absorption bands. The positions absorption bands of Co ions were analyzed in the context of ligand field parameters determinations. The obtained data of the crystal field splitting parameter (10Dqt) showed decreased values from 3451 cm−1 to 3364 cm−1 with more SnO2 addition. While Racah parameter B values were also, attained showing increased values from 967 cm−1 to 985 cm−1 when additional SnO2 is added. Further, the impacted role of SnO2 addition on the structural and optical properties of the present glasses was finally estimated.

Influence of subphase temperature on Langmuir layers and thin films of A3B-type porphyrine derivative

The influence of aqueous subphase temperature on the formation and stability of floating layers of 5-(4-hydroxyphenyl)-10,15,20-tris(4-hexadecyloxyphenyl)porphyrin (P-OH) was investigated using the Langmuir technology. It was found that the increase in the subphase temperature from 1 to 40 °C leads to a loosening of floating layers (an increase in the area per molecule in the floating layer by ∼15% and a decrease in the surface compression modulus by more than two times). The stability of floating layers (i.e., the ability of a floating layer to maintain its area under the action of a constant compressive force) decreases with increasing subphase temperature. It has been shown that the most stable floating layers are formed at subphase temperatures lower than 30 °C. Monolayer films on solid substrates were obtained using the Langmuir-Schafer technique at subphase temperatures of 1, 10, 20, 30, and 40 °C. The surface relief of these films was studied by atomic force microscopy (AFM). The AFM analysis revealed that the films transferred from the aqueous subphase at a temperature of 20 °C had the highest continuity and the lowest roughness. The absorption spectra of the floating layers were obtained, in which a bathochromic shift of the Soret band and Q-bands were registered (by 19 nm at 20 °C) in comparison with chloroform solution spectrum. This shift is a consequence of the strong intermolecular π–π* interaction, resulting in the formation of J-type aggregates. The Soret band in the spectra of the floating layers shifted from 436 to 441 nm with an increase in subphase temperature from 1 to 40 °C. In the absorption spectra of thin films (8 transfers), the indicated shifts of absorption bands as well as a broadening of the Soret band are preserved. The results of this work can be used in the targeted creation of film samples with specific structure and properties.

Porphyrin Photosensitizers into Polysaccharide-Based Biopolymer Hydrogels for Topical Photodynamic Therapy: Physicochemical and Pharmacotechnical Assessments.

Photodynamic therapy (PDT) is an emerging treatment modality that utilizes light-sensitive compounds, known as photosensitizers, to produce reactive oxygen species (ROS) that can selectively destroy malignant or diseased tissues upon light activation. This study investigates the incorporation of two porphyrin structures, 5-(4-hydroxy-3-methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.2.) and 5,10,15,20-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1.), into hydroxypropyl cellulose (HPC) hydrogels for potential use in topical photodynamic therapy (PDT). The structural and compositional properties of the resulting hydrogels were characterized using advanced techniques such as Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), atomic force microscopy (AFM), UV-Visible (UV-Vis) spectroscopy, and fluorescence spectroscopy. FTIR spectra revealed a slight shift of the main characteristic absorption bands corresponding to the porphyrins and their interactions with the HPC matrix, indicating successful incorporation and potential hydrogen bonding. XRD patterns revealed the presence of crystalline domains within the HPC matrix, indicating partial crystallization of the porphyrins dispersed within the amorphous polymer structure. TGA results indicated enhanced thermal stability of the HPC-porphyrin gels compared to 10% HPC gel, with additional weight loss stages corresponding to the thermal degradation of the porphyrins. Rheological analysis showed that the gels exhibited pseudoplastic behavior and thixotropic properties, with minimal impact on the flow properties of HPC by P2.1., but notable changes in viscosity and shear stress with P2.2. incorporation, indicating structural modifications. AFM imaging revealed a homogeneous distribution of porphyrins, and UV-Vis and fluorescence spectroscopy confirmed the retention of their photophysical properties. Pharmacotechnical evaluations showed that the hydrogels possessed suitable mechanical properties, optimal pH, high swelling ratios, and excellent spreadability, making them ideal for topical application. These findings suggest that the porphyrin-incorporated HPC hydrogels have significant potential as effective therapeutic agents for topical applications.

Effects of Planarization of the Triphenylamine Unit on the Electronic and Transport Properties of Triarylamine-Fluorene Copolymers in Both Doped and Undoped Forms.

Triarylamine-alt-fluorene (TAF) copolymers are widely used for hole injection and transport in organic electronics. Despite suggestions to planarize the triphenylamine moiety, little research has been conducted. Here, we report a comprehensive investigation of the effects of planarization on the electronic and transport properties of a model TAF polymer semiconductor core. We compared the conventional twisted-propeller N-4-methoxyphenyl-N,N-diphenylamine-4',4″-diyl (TA) unit and its planarized bridged analogue (bTA) where adjacent o,o'-positions are linked by 1,1-dimethylmethylene. We studied both polyelectrolyte and non-polyelectrolyte forms of this core in both doped and undoped states. We found that planarization leads to an unprecedented trap-free transport of holes, and a pronounced enhancement of their mobility in the undoped state though less so in the doped state. Planarization also induces a slight reduction in the ionization energy of the undoped polymer, consequently lowering the work function of the doped polymer. This is accompanied by small spectral shifts: a red shift in the first absorption band of the undoped polymer and a blue shift in the first absorption band of the polaron. Furthermore, this study unveils new fundamental features of TAF polymers: (i) Doping induces the formation of three polaron bands within the subgap. (ii) Absorption of both neutral and polaron segments exhibit a linear intensity relationship with doping level. (iii) Electrical conductivity reaches a maximum at the half-doped state, varying as σ ∼ (x (1 - x))3 for 0.1 ≲ x ≲ 0.9, where x is the doping level. Finally, we demonstrate the successful integration of these self-compensated hole-doped TAF polymers as efficient hole injection layers in organic semiconductor diodes.

Investigating extrusion impact on functional, textural properties, morphological structure, and molecular interactions in hulless barley-based extruded snacks supplemented with mung bean.

The effect of varying extrusion conditions on the functional properties of hulless barley-mung bean (70:30) extruded snacks was investigated using response surface methodology with feed moisture (FM), barrel temperature (BT), and screw speed (SS) as process variables. Results revealed significant impacts on functional characteristics with varying extrusion conditions. Bulk density (BD) of extruded snacks ranged from 0.24 to 0.42 g/cm3, showing that lower FM and higher BT results in lower BD while it increased with increasing FM, SS, and BT. The expansion ratio (ER) of extruded snacks ranged between 2.03 and 2.33, showing BT and SS had a desirable positive effect, whereas increasing FM led to decreased ER. Increasing BT and SS depicted a negative effect on water absorption index, whereas FM showed positive effect, which ranged between 4.21 and 4.82 g/g. A positive effect on water solubility index was depicted by BT and SS, which ranges between 9.01% and 13.45%, as higher SS and BT led to starch degradation and increased solubility suggesting better digestibility. The hardness of extruded snacks ranged from 32.56 to 66.88 Newton (N), showing increasing FM increased hardness, whereas higher SS and BT resulted in lowering the hardness. Scanning electronic microscope (SEM) analysis revealed structural changes in extrudates in comparison with nonextruded flour, indicating starch gelatinization and pore formation affected by varying processing parameters. Shifts in absorption bands were observed in Fourier transform infrared spectroscopy (FT-IR), suggesting structural changes in starch and protein. Understanding the effects of extrusion parameters on product properties can help tailored production to meet consumers' preferences and the development of functional snacks with improved nutritional quality.

Tunability of impedance spectroscopy, electrical conductivity and optical properties of Cu-doped TiO2 nanostructures for optoelectronic device application

This paper details the successful fabrication of Cu-doped TiO2 nanostructures using a co-precipitation method. A thorough analysis of the structural and electrical characteristics of the nanostructure samples was carried out. It was found that all synthesized samples exhibited an anatase TiO2 structure. The XRD pattern indicated an average crystalline size of 23.19 nm for Cu-doped TiO2 nanostructures, whereas TiO2 nanostructures showed a size of 11.78 nm. The UV-Visible spectrum indicated a noticeable absorption band shift towards longer wavelengths, coupled with an increased absorption rate of light. Analysis of electrical conductivity showcased temperature-dependent variations in conductivity at high frequencies. Impedance spectroscopy unveiled improved conductivity upon the integration of Cu into TiO2 nanostructures. Nonetheless, at 300 K, copper doping resulted in a decline in electrical conductivity, whereas at elevated temperatures, Cu doping showed a increase in conductivity for the nanostructures samples. These findings underscore the potential and applicability of the nanostructures, showcasing improved AC conductivity and electrical characteristics, making them promising for various electrical applications.

On the Solvatochromism of Fluorescein Sodium

Fluorescein sodium is a very important compound for a wide spectrum of applications, from which medical applications prevail. Despite this, there are very few studies in the literature related to the structure and fundamental properties of fluorescein sodium and its solutions, with most of the studies dealing with fluorescein. The purpose of the present article is to determine some parameters of the fluorescein sodium molecule approaching the quantum-mechanical modeling and experimental solvatochromism in both binary and ternary solutions. For data analysis, several theoretical models were applied. The results highlight the intermolecular interactions involved in the spectral shift of the electronic absorption band of fluorescein sodium when dissolved in different solvents or binary solvents and allowed the estimation of the difference between the interaction energy in molecular pairs of the type of fluorescein sodium − solvent 1 and fluorescein sodium − solvent 2. By applying a variational method, the dipole moment in the first excited state of the fluorescein sodium molecule and the angle between the dipole moments in the ground and excited states, respectively, were estimated. These results are useful for a better understanding of the behavior of fluorescein sodium when dissolved in different solvents or combinations of solvents, to develop new practical applications.

Methyl‐ and Methoxy‐substituted 2‐(Pyridin‐2‐yl)‐4‐(4‐aminophenyl)quinazolines: Synthesis and Photophysical Properties

AbstractA series of novel 2‐(2‐pyridyl)quinazoline luminophores containing a donor aryl fragment at position 4 and methyl or methoxy groups at benzene ring has been synthesized by efficient three‐step route. The linear optical properties have been studied by UV/Vis absorption and photoluminescence spectra in two solvents. We revealed that introduction of additional methyl group or the replacement of methyl substituents with methoxy ones lead to sequentially shift of absorption and emission maximum to blue region. 9H‐Carbazol‐9‐yl‐containing derivative is characterized by hypsochromically shifted absorption band compared to its NEt2 and NPh2 counterparts. Unlike 9H‐carbazol‐9‐yl‐derivative, Et2N‐ and Ph2N‐bearing quinazolines demonstrate considerable decrease in quantum yield values when going from toluene to MeCN. Solvatochromic properties have been explored, the pronounced bathochromic shift was observed in fluorescence spectra with the increase of solvents polarity. Moreover, the compounds show significant shift of emission band with the increase of water fraction in DMSO/H2O mixture. Two‐photon optical properties have been also studied, the two‐photon absorption cross‐sections in MeCN and toluene reached 120 GM and 210 GM, respectively. The presence of additional methyl group has little impact on δTPA value, while introduction of methoxy substituents dramatically decreases TPA cross sections. Additionally, a quantum‐chemical calculations of synthesized compounds were performed to support the experimental data.

Red Shift in the Absorption Spectrum of Phototropin LOV1 upon the Formation of a Semiquinone Radical: Reconstructing the Orbital Architecture.

Flavin mononucleotide (FMN) is a ubiquitous blue-light pigment due to its ability to drive one- and two-electron transfer reactions. In both light-oxygen-voltage (LOV) domains of phototropin from the green algae Chlamydomonas reinhardtii, FMN is noncovalently bound. In the LOV1 cysteine-to-serine mutant (C57S), light-induced electron transfer from a nearby tryptophan occurs, and a transient spin-correlated radical pair (SCRP) is formed. Within this photocycle, nuclear hyperpolarization is created by the solid-state photochemically induced dynamic nuclear polarization (photo-CIDNP) effect. In a side reaction, a stable protonated semiquinone radical (FMNH·) forms undergoing a significant bathochromic shift of the first electronic transition from 445 to 591 nm. The incorporation of phototropin LOV1-C57S into an amorphous trehalose matrix, stabilizing the radical, allows for application of various magnetic resonance experiments at ambient temperatures, which are combined with quantum-chemical calculations. As a result, the bathochromic shift of the first absorption band is explained by lifting the degeneracy of the molecular orbital energy levels for electrons with alpha and beta spins in FMNH· due to the additional electron.

Exploring copper (II) porphyrin complexes and their derivatives for electrochemical analysis and biological assessment in the study of breast cancer (MCF-7) cell lines

In this study, several derivatives of tetraphenylporphyrin were synthesized, each with unique meso-substituent groups including phenyl, methoxyphenyl, butyloxyphenyl, octyloxyphenyl, and dectyloxyphenyl. Additionally, their corresponding copper complexes were prepared and thoroughly characterized. The structural confirmation of all compounds was established through CHN elemental analysis, mass spectrometry, and FT-IR spectroscopy. As the number of carbon atoms in the alkyl long-chain increased, a slight red shift in the electronic absorption band was observed, which was attributed to the electronic influence of the alkyl group. DFT analysis indicated that electron density predominantly localized on the porphyrin ring of both the metal free porphyrins and copper (II) porphyrin complexes, with relatively low electron density in the p orbital of the meso-aryl long-chain substituent group. EPR spectroscopy of the Copper (II) ion complexes revealed signals, indicating their paramagnetic properties. Additionally, the Copper (II) tetraphenylporphyrin (CuTPP) complexes displayed two reversible oxidation peaks at +0.97 V and +1.35 V, whereas other derivatives exhibited lower oxidation potentials. The cytotoxicity of these compounds against MCF-7 cell lines was assessed using MTT assay, revealing cytotoxic effects in all cases. Among them, Copper (II) tetrakis (4-methyloxyphenyl)porphyrin (CuTOMPP) demonstrated the highest potential, with an IC50 value of 32.07 μg/mL.

Solvatochromic and Computational Study of Some Cycloimmonium Ylids

This article contains a comparative spectral analysis corroborated with the quantum mechanical computations of four cycloimmonium ylids. The spectral shift of the visible electronic absorption band of the studied molecules in 20 solvents with different empirical parameters is expressed by linear multi-parametric dependences that emphasize the intramolecular charge transfer (ICT) process. The nature of molecular interactions and their contribution to the spectral shift of the visible ICT band of solutes are also established in this manuscript. The results of the statistical analysis are used to estimate the cycloimmonium ylids’ excited dipole moment by the variational method, using the hypothesis of McRae. The importance of the structure of both the heterocycle and carbanion substituents to the stability and reactivity of the studied cycloimmonium ylids is underlined by the quantum mechanical computations of the molecular descriptors.

Iron oxide (Fe3O4) and ciprofloxacin loaded magnetic nanoparticles for magnetic drug targeting

Iron oxide (Fe3O4) pristine and ciprofloxacin loaded nanoparticles are synthesized successfully using co-precipitation method. X-ray diffraction analysis confirms the pure phase formation of the synthesized Fe3O4 particles. The grain size of the Fe3O4 calculated from the SEM images comes out to be 50 nm. UV-VIS spectrophotometric analysis indicates the accuracy of the results in which an absorption maximum of blank and ciprofloxacin containing iron oxide (Fe3O4) particle was observed at 260 and 265 nm respectively. The spectrum band shows the maximum absorption band shift of around 4-5 nm which may be explained by the drug conjugation to the Fe3O4 nanoparticles. The spectrum indicates the formation of Fe3O4 magnetic nanoparticles having black color and obtained material is found with energy band gap (E) of 2.12 eV and 2.19 eV. On the basis of the findings from dynamic light scattering (DLS) results, it can be concluded that overall particle size of magnetic iron oxide nanoparticles is observed as 765 nm. In the present study the polydispersity index (P.I.) of bare Fe3O4 magnetic nanoparticles is 0.221, which indicate the hydrodynamic property of the synthesized particles.