Maximum Absorption Wavelength Research Articles

Simultaneous UV Spectrophotometric Method for Estimation of Berberine and Withanolide in Polyherbal Immunity Booster Dosage Form

The majority of commercial herbal preparations used to improve immunity lack standardization with regard to the active ingredients marker molecules. The objective of present study is the simultaneous estimation of berberine and withanolide in herbal immunity booster tablet using UV spectrophotometric method. The method was validated according to ICH guidelines. The results indicated that berberine and withanolide have maximal absorption wavelength i.e. λmax at 348 nm and 231 nm, respectively. Withanolide and berberine were found to behave linearly over the concentration range of 5–25μg/mL with R2 value of 0.9998 and 0.9999, respectively. Withanolide and berberine have shown % relative standard deviation (RSD) values of 0.07 and 0.09, respectively, in accuracy study. The intraday and interday precision was deemed adequate with a % RSD fewer than 2. Further, the limit of detection (LOD) and limit of quantization (LOQ) value for berberine and withanolide were found to be 0.12 mg/mL and 0.35mg/mL and 0.07, 0.20 mg/mL, respectively. In conclusion, the proposed method was validated in accordance with the International Conference on Harmonization (ICH) guidelines. The developed method can be employed to determine how much berberine and withanolide are present in pharmaceutical preparations.

Synthesis and properties of thieno[3,2-b]thiophene appended triarylamine radical cations: Near-infrared absorbing dye with absorption beyond 1400 nm

Two triphenylamines with thieno [3,2-b] thiophene units were designed and synthesized. The radical cations obtained by the one-electron oxidation of these amines show a significant absorption in the near-infrared region. In particular, the derivative with three hexyl groups has excellent solubility, and its radical cation has a maximum absorption wavelength above 1400 nm. DFT calculations support these experimental results. A novel design strategy for NIR-II dyes is described.

Theoretical studies of electronic and optical characteristics in donor-π-Acceptor (D-π-A) dyes: DFT and TD-DFT methods

Abstract This research focused on enhancing D-π-A organic dyes derived from coumarin and its derivatives, collectively referred to as D-CM-A dyes. The study aimed to improve these dyes by introducing various donors and acceptors to the coumarin structure. Six new coumarin dyes were evaluated, primarily for their potential application in dye-sensitized solar cells (DSSCs) to enhance energy efficiency. The analysis involved calculating the geometry, electronic properties, and optoelectronic characteristics of the dye molecules using DFT and TD-DFT methods with the B3LYP functional and the 6-311G basis set in both gas and solvent phases. The primary focus was to understand how modifications to the π-conjugated D-π-A organic dyes influenced their optoelectronic properties, including key factors such as maximum absorption wavelength (λmax), highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO), and energy gap (Egap). Additionally, the study explored the photovoltaic properties of these dyes. The findings highlighted D4-CM-A4 as a promising candidate with the narrowest energy gap, while D1-CM-A1 and D2-CM-A2 showed superior light-harvesting efficiencies (LHE) compared to other derivatives. In conclusion, this study suggests that D1-CM-A1 and D2-CM-A2 are favourable choices for enhancing the performance of DSSCs due to their promising optoelectronic properties.

Rapid colorimetric assay based on the oxidation of 2,2-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid-diammonium salt for nitrite detection in meat products

This work developed a rapid colorimetric method for nitrite detection in meat products. The detection was based on the reaction of nitrite with 60 mM HCl to produce radicals which further oxidized ABTS (50 µM) to form a water-soluble blue-green product (ABTS•+). The absorbance was measured at a maximum absorption wavelength of 412.5 nm. Parameters such as concentration of HCl, concentration of ABTS and reaction time were evaluated. The absorbance was linearly proportional to the concentration of nitrite (0.1–20 µM) with the limit of detection of 0.34 µM. The proposed method was a time-saving assay since it required only 2 min to complete one measurement. There was no effect of the interference produced by other ions. The assay was robust with 2.5%RSD (n = 50). In meat product samples, high accuracy was observed with the recoveries between 100 ± 2.2% and 105 ± 3.7%. The amount of nitrite in meat products detected by the ABTS method was found in the range of 5.41 − 7.62 mg/kg. The conventional Griess method was applied to determine nitrite in the same meat products. There was no statistically significant difference between the two methods (P = 0.05).

Theoretical and experimental studies on sulfasalazine interactions with poly (lactic acid): Impact of hydrogen bonding and charge transfer interactions on molecular structure, electronic and optical properties

The interaction between sulfasalazine (SSZ) through different functional groups and poly (lactic acid) (PLA) in the chloroform phase was investigated in this study using density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods. The binding energy and thermodynamic parameters show that the hydrogen double bond interaction between SSZ and PLA in state I (−0.71 eV) is stronger than in states II (−0.64 eV) and III (−0.51 eV). The SSZ and PLA interaction results in an enhanced dipole moment, greater solubility, and more negative values for Gibbs free energy (ΔGsolv) and energy gap (Eg). Considerable changes in absorption peaks of SSZ and PLA indicate surface adsorption of the drug (SSZ) into the carrier (PLA) in UV–Vis spectra. Theoretical UV–Vis analysis demonstrates SSZ interaction with PLA happens in the ultraviolet region with a maximum absorption peak at 380 nm, which is close to experimental UV–Vis analysis. The experimental spectra showed minimal variations in the maximum absorption wavelength, with respect to theoretical calculations. The presence of SSZ was found to cause a modification in the structure of PLA, as evidenced by both experimental and theoretical Infrared (IR) spectra.

Response of the FBX aqueous chemical dosimeter to high energy proton and electron beams used for radiotherapy research

The response of the FBX aqueous chemical dosimeter to 10 MeV electron and 100 MeV proton beams was investigated, and the results were compared with those obtained for cobalt-60 gamma rays over a dose range of 0–30 Gy. The sensitivities of the FBX dosimeter in which the absorbance values were measured at the wavelength of maximum absorption (λmax) and 548 nm are approximately the same and amount to 0.091, 0.088, and 0.081 Gy-1 for 10 MeV electrons, cobalt 60 γ-rays, and 100 MeV proton beams, respectively. The corresponding calibration coefficients are 10.99, 11.36, and 12.35 Gy, in their respective order. The molar absorption coefficients that were calculated for cobalt-60 gamma rays amount to 17824 ± 560, 16417 ± 248, and 17694 ± 437 M−1cm−1 at the wavelengths λmax, 540 nm, and 548 nm, respectively. The radiation chemical yield-G (Fe3+) at the wavelengths of λmax and 548 nm has approximately the same values and amounts to 51.1 × 10−7, 49.4 × 10−7, and 45.4 × 10−7 mol.J−1 for 10 MeV electrons, cobalt-60 γ-rays, and 100 MeV proton beams, respectively, and both of them are lower by ∼ 8% than that obtained at the wavelength of 540 nm. A linear response of the FBX dosimeters prepared in the current study was achieved up to 12 Gy, compared with the linear response up to 5 Gy reported in the previous literature. Furthermore, by measuring the absorbance values at the wavelength of the isobestic point, i.e., 555 nm, the linearity of the FBX dosimetric solution may be extended to cover the entire dose range used, i.e., 0.2–30 Gy. Consequently, with good reproducibility (less than 1%), the prepared FBX dosimeter can be utilized for radiotherapy research over the dose range of 0.2–30 Gy.

"Optimizing Pharmaceutical Formulations: Advancements in Nanosuspension Pre-Formulation to Enhance Solubility and Bioavailability of Active Agents"

This study aimed to enhance the bioavailability of a poorly water soluble drug by developing a nanosuspension through an innovative formulation method. The nanosuspension was produced with meticulous attention to the materials reliability and excellent quality. Nepafenac was characterised in the pre-formulation study by establishing its melting point, solubility in different solvents, organoleptic properties, and creating a calibration curve. We utilised UV spectroscopy to determine the maximum wavelength (?max) of Nepafenac and construct a standard calibration curve in ethanol. To ensure the compatibility of the medicine with the polymers (Pluronic F127 and HPMC E 5), Fourier Transform Infrared Spectroscopy (FTIR) was utilised for drug interaction analysis. The nanosuspension was produced using the solvent diffusion approach. The effect of different concentrations of Poloxamer 407 and HPMC E 5 on the formulation's effectiveness was investigated experimentally using a 32 complete factorial design. We used Response Surface Methodology (RSM) and statistical analysis to enhance the formulation concerning in vitro release, particle size, and viscosity. The pre-formulation characteristics of Nepafenac met the standards outlined in the Pharmacopoeial regulations. The maximum absorption wavelength (?max) of Nepafenac was confirmed by UV spectroscopy, and a reliable calibration curve was created. The FTIR analysis showed no chemical interaction between the medicine and polymers. RSM and experimental design indicated that Poloxamer 407 and HPMC E 5 had a substantial impact on the performance of the nanosuspension. Analysis of variance (ANOVA) confirmed the model and parameters that influence controlled drug release percentage, particle size, and viscosity. Optimal conditions for enhancing drug delivery and reducing particle size were determined by the analysis of contour and response surface plots. The optimal parameter values, as indicated in the desirability plots, closely matched the anticipated values. The experimentation confirmed the viability and effectiveness of the nanosuspension formulation generated based on the RSM findings.

Effect of electron donor groups on the performance of benzothiadiazole dyes with simple structures for dye-sensitized solar cells

Three structurally simple metal-free organic dyes (C1, C2 and C3) with D–A–π–A structure, having benzothiadiazole auxiliary acceptor, benzene π-bridge and cyanoacrylic acid anchoring group, were designed and synthesized for use in dye-sensitized solar cells (DSSCs). Diphenylamine, carbazole and phenothiazine were used as electron donor groups and their effects on the photovoltaic performance were investigated. It was found that C1 dye with diphenylamine donor has the longest maximum absorption wavelength and highest molar extinction coefficient, which is benefical for harvesting more photons and generating a higher photocurrent. Therefore, the DSSC based on C1 dye gives a power conversion efficiency (PCE) of 5.01 %, which is greater than those of C2 dye with carbazole donor (3.51 %) and C3 dye with phenothiazine donor (1.76 %). Finally, the co-sensitization of C1 and C2 exhibits a highest PCE of 5.49 % may be due to broader visible light absorption.

Evaluation of Avocado Peels Dye as Sensitizer in Dye-Sensitized Solar Cells by Experiment and Computational Intelligence

This work was designed to evaluate the unmodified and modified natural dye obtained from a sensitizer in dye-sensitized solar cells using experimental and computational approaches. Natural dye (APPE) was extracted from Avocado pear (Persea Americana) peels and chemically modified into nanocomposite by a one-pot reaction with silver nitrate. The modified dye was characterized by UV-Vis spectroscopy, X-ray diffraction (XRD) spectroscopy, Energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The APPE and APPE-AgNPs composite show maximum wavelength of light absorption at 542 nm and 493 nm respectively. Both APPE and APPE-AgNPs were evaluated as sensitizers for dye-sensitized solar cells (DSSC). The APPE-AgNPs dye afforded a higher power conversion efficiency of 0.93% compared to 0.44% for APPE. Current-voltage responses and photo-electrochemical properties were determined at one sun illumination. The electronic properties of the major phyto-compounds in the dye, namely perseorangin and cyanidin associated with light harvesting and sensitization were modeled using a quantum chemical computational approach. The power conversion efficiency of APPE-AgNPs obtained from this study compares with other plant-based dye sensitizers and hence could be deployed for practical application.

Establishment of simultaneous analysis validation for Perilla frutescens var. acuta extract

In this study, the UV spectra maximum absorption wavelengths and molecular weights of major compounds 1–3 were identified in Perilla frutescens var. acuta extract using high-performance liquid chromatography (HPLC)-DAD and HPLC-MS/MS. Luteolin-7-O-diglucuronide (1), scutellarin (2), and rosmarinic acid (3) were identified, and simultaneous analysis validation was performed for quantification using HPLC-DAD. All linearities showed R2 values of 0.9993 or higher, and the limits of detection and quantification were measured in the ranges of 4.4802–5.4133 and 13.5764–16.4038 µg/mL, respectively. The relative standard deviation (RSD) values for accuracy ranged from 0.09 to 0.89%, and the recovery rates were in the range of 99.36–101.96%. The precision RSD values within the laboratory were in the range of 0.05–1.04%, and the RSD values for repeatability evaluation were below the guideline criteria of 2%. The content change of the three marker compounds within 24 h was 0.36–0.69%, confirming the chemical stability of the extract within 24 h, which was below the guideline criteria of 2.0% established by the Ministry of Food and Drug Safety guidelines. The content analysis of the extract according to ethanol concentration showed that luteolin-7-O-diglucuronide had the highest content of 302.22 µg/mL in the 0% ethanol extract, while scutellarin and rosmarinic acid showed the highest contents of 103.61 and 118.77 µg/mL, respectively, in the 60% ethanol extract.

Development and Validation of Simultaneous Quantitative Dissolution Analysis for the Two Active Pharmaceutical Ingredients in Dapagliflozin Propanediol Monohydrate-sitagliptin Phosphate Monohydrate Multi-layered Tablets

Background: Recently, a combination prescription with the main ingredients sitagliptin and dapagliflozin as dipeptidyl peptidase-4 andsodium–glucose cotransporter-2 inhibitors, respectively, for the treatment of type 2 diabetes has widely been issued in hospitals. However, the development of double-layered tablets requires simultaneous quantitative dissolution tests that are significantly efficient and cost-effective. Objective: Individual analysis of the two active pharmaceutical ingredients (APIs) incurs more than twice the time and cost. Consequently, this study aimed to develop a dissolution analysis method that simultaneously quantifies the APIs dapagliflozin and sitagliptin in multi- layered tablets. This simultaneous quantitative dissolution analysis can dramatically reduce analysis time and cost. Methods: For reversed-phase high-performance liquid chromatography (RP-HPLC) analysis using ultraviolet detection, a Zorbax C18 column (4.6 × 150 mm, 5 μm) was used, and the flow rate was 1.5 mL/min, injection amount 20 μL, and maximum absorption wavelength set to 205 nm. Additionally, the analysis time was set to 1.5 times the retention time of dapagliflozin Results: The retention times of dapagliflozin and sitagliptin were 11.57 and 2.56 min, respectively. Further, their relative standard deviations were 0.11% and 0.05%, respectively. Quantitative analysis using RP-HPLC confirmed no peak interference between the APIs and excipients. Both APIs exhibited linearity at a 20–120% concentration. Conclusion: The dissolution method developed in this study can quantify both APIs simultaneously, thereby reducing analysis time and cost by more than 50% and increasing efficiency in the pharmaceutical industry.in the pharmaceutical industry.

Development and Validation of a UV Spectroscopic Method to Estimate Eltrombopag Olamine along with Bulk and In-house Formulation

The current UV Spectroscopic method developed involving ethanol as a solvent is simple, fast, specific, precise, and sensitive for the estimation of Eltrombopag Olamine in bulk in day-to-day analysis. As per the ICH Q2 (R1) guideline, the method was validated. Eltrombopag Olamine is a drug used to treat thrombocytopenia (a low blood platelet count) in adults and youngsters with chronic immune idiopathic thrombocytopenic purpura that didn't get well with different treatments. Eltrombopag Olamine is additionally accustomed to treating severe aplastic anemia. It’s conjointly being studied within the treatment of different conditions and kinds of cancer. Eltrombopag Olamine binds to the thrombopoietin receptor, which causes the bone marrow to create more platelets. It’s class of thrombopoietin receptor agonists, also known as Promacta. Eltrombopag is also recently approved (2012) for the treatment of thrombocytopenia in a patient with chronic hepatitis C to start and sustain interferon-based therapy. The solvent used in the entire method development and validation was ethanol. The maximum wavelength of absorption was found to be 423nm. Beer’s law was obeyed in the concentration range of 5 to 30ug/ml with a correlation coefficient of 0.9966. The method was precise with an RSD of less than 2%, the LOD, and LOQ were found to be 6.18ug/ml and 18.7ug/ml respectively, % recovery of the drug is 98 to 100%. The method was validated for linearity, precision, accuracy, and robustness and all parameters were found to be satisfactory which proves that this method can be used for routine analysis of Eltrombopag Olamine.

Novel bis-chalcone-based carbazole derivative photoinitiators for visible light polymerization with good photobleaching and biocompatibility

Four novel bis-chalcone-based carbazole derivative photoinitiators (2E,5E)-2,5-bis((9-phenyl-9H-carbazol-3-yl)methylene)cyclopentan-1-one (KZA), 2,5-bis((E)-4-(9H-carbazol-9-yl)benzylidene)cyclopentan-1-one (KZB), (2E,5E)-2,5-bis((9-ethyl-9H-carbazol-3-yl)methylene)cyclopentan-1-one (KZC) and (2E,5E)-2,5-bis((5-(9-ethyl-9H-carbazol-3-yl)thiophen-2-yl)methylene)cyclopentan-1-one (KZD) were successfully designed and synthesized. Their maximum absorption wavelengths were 440 nm, 405 nm, 446 nm and 500 nm, respectively, and they all had high molar extinction coefficients. Furthermore, three-component photoinitiation system including bis-chalcone/iodonium/amine could quickly and efficiently trigger the photopolymerization of acrylates. For example, PEGDA coatings could cure in 10 s and the CC bond conversion exceeded 90 % in the end. Then we also conducted photosteady-state degradation, fluorescence quenching, cyclic voltammetry and ESR experiments to investigate the mechanisms of photopolymerization. Besides, all four bis-chalcones showed good photobleaching and biocompatibility, which was suitable for use in 3D printing and deep coating curing. For instance, the LCD 3D printer successfully printed clear and photobleached objects with KZD/iodonium/amine system. All these excellent properties indicated the industrial application potential of the four carbazole derivatives in visible light curing.

Convenient and facile theoretical design strategy to amplify NLO response of N‐doped‐indolo[3,2,1‐jk]carbazole push–pullA‐π‐D‐π‐A switches

AbstractBACKGROUNDNonlinear optical (NLO) materials play a crucial role in various technological fields, making it important to develop strategies that enhance their properties. This research paper focuses on the design strategy to enhance the NLO response of indolo[3,2,1‐jk]carbazole‐based N‐doped fused‐ring electron acceptors as its five new A‐π‐D‐π‐A switches.RESULTSThe chromophores IC1–IC5 were studied for their electronic, NLO, charge transfer, UV–visible and natural bond orbital‐related features. Their energy levels were determined, with IC1 having the highest energy (3.12 eV) and IC5 the lowest energy (1.916 eV). Their corresponding maximum absorption wavelengths (λmax) were determined to range from 398 to 647 nm. Their electronegativity (x), chemical potential (μ), hardness (η), softness (σ) and electrophilicity of the chromophores were also analyzed, having values ranging from 3.00 to 3.47 eV, 47 to −3.0 eV, 0.25 to 1.39 eV, 0.36 to 2.04 eV and 3.23 to 23.81 eV, respectively. The η and σ values indicated the stability and reactivity of the chromophores, with IC1 having the lowest η and highest σ values. IC2 had the highest dipole moment (μtot) (9.23D) and hyperpolarizability (β0) of 10.323 × 10−11 esu, indicating its strong NLO response. Among all, chromophore IC1 demonstrated a robust stabilization energy by its (N1) → (C15–C17)π* transition.CONCLUSIONThe proposed theoretical design strategy successfully amplifies the NLO response of N‐doped‐indolo[3,2,1‐jk]carbazole switches to open up possibilities for the development of advanced NLO materials, paving the way for future applications in photonics, optoelectronics and other emerging technologies. © 2023 Society of Chemical Industry (SCI).

Synthesis, photophysical properties and nonlinear response of a bisquinoline A-D-A with aggregation-induced emission for potential application in optoelectronic devices

The present work reports the synthesis and characterization of a bisquinoline (BQT) with very attractive aggregation-induced emission (AIE) and optical nonlinear response. BQT was characterized by FTIR spectroscopy and mass spectrometry to confirm the product obtained. Linear optical characterization was performed using UV-Vis and fluorescence spectrophotometry. Maximum absorption and emission wavelengths of 408 nm and 539 nm, respectively, were determined in solution; the optical band gap on the film is 1.95 eV. BQT exhibits aggregation-induced emission (AIE), a property exhibited by some fluorescent molecules that broaden the range of applications in which they can be used. BQT exhibits two-photon absorption with a negative nonlinear refractive index. This response is associated with the charge transfer processes that favour the A-D-A architecture of the molecule. Their HOMO and LUMO energy levels (-5.39 eV and -3.67 eV, respectively) and electrochemical band gap (-1.72 eV) were determined by cyclic voltammetry; these values indicate that BQT is an attractive organic semiconductor which energy levels could match those required for photovoltaic applications. The results suggest that BQT is an attractive material for its application in optoelectronic devices such as OLEDs and nonlinear optical applications.

Modeling of a Broadband Microwave Composite Thin Film Absorber.

Composite thin film absorbers show superior performance and have a wide range of applications. Obtaining a broadband composite thin film absorber is a challenge. In this work, we proposed a modeling of a broadband microwave composite thin film absorber based on the impedance matching theory and equivalent circuit model of the square loop. The unit cell of the absorber was composed of metal square loops with high magnetic conductivity deposited on the polyethylene substrate, and an FR-4 (epoxy glass cloth) substrate was the spacer substrate layer. The simulation results show that the absorptivity of the absorber reached more than 90% in the frequency range of 8.7-18 GHz for TE and TM waves under normal incidence. The thickness of the designed absorber was 2.05 mm (0.059 λmax, λmax corresponds to the maximum absorption wavelength). The simulation results show that the energy distribution in the proposed absorber was mainly localized in the top metal FSS layer due to the ohmic loss of metal, and the dielectric loss played a small role in the absorption of the absorber. Our work provides a design approach to improve the efficiency of optoelectronic devices and thermal detectors and has application prospects in radar and aircraft stealth applications.

Novel strategy toward color-tunable and glow-in-the-dark colorless smart natural wooden window

Smart windows that use photochromic colorless wooden materials are an intriguing and urgent area of research. Herein, we create afterglow transparent woods with UV-induced photochromic capability. Infiltrating a lignin-modified wood (LMW) with a solution of methyl acrylate (MA) and rare-earth strontium aluminum oxide (SrAl2O4: Eu2+, Dy3+; SAOED) yielded afterglow and photochromic translucent wood. Preparing photoluminescent transparent wood effectively requires dispersing SAOED phosphor nanoparticles (NPs) in pre-polymerized MA without clumping. CIE (Commission Internationale de ĺEclairage) Lab colorimetric studies indicated that this transparent timber substrate changed color from colorless in daylight to greenish when exposed to ultraviolet rays. Micrographs taken using a transmission electron microscope (TEM) were analyzed to learn more about the morphology of the synthesized SAOED NPs. Different characterization techniques were applied on the photochromic translucent wood samples, including scanning electron microscopy (SEM), energy-dispersive X-ray analyzer (EDX), hardness properties, wavelength-dispersive X-ray fluorescent spectroscopy (WD-XRF), and absorption and emission spectroscopy. Absorption maximum wavelength was detected at 365 nm. Both 436 nm and 517 nm were observed as emission wavelengths in the developed photoluminescence wood. The results displayed that the manufactured transparent wood introduced superior protection from UV radiation and superhydrophobic activity. UV light triggered a rapid and reversible photochromic reaction in the transparent luminous wood.

Theoretical study of static and frequency-dependent nonlinear optical properties of 1-phenyl-2,5-di(thiophen-2-yl)-1H-pyrrole based D-π-A chromophores through π-linkers modifications: A gateway towards giant nonlinear optical compounds

Designing materials with proficient nonlinear optical (NLO) amplitudes is the frontier area of research. To address the briskly mounted demand for potentially useful NLO materials in optoelectronic and electrical applications, static and frequency-dependent NLO response properties of 1-phenyl-2,5-di(thiophen-2-yl)-1H-pyrrole (PDTP) based D-π-A chromophores were computed at 1907.21 nm, 532 nm, and 1064 nm laser wavelength for exploring SHG β (−2ω, ω, ω) and EOPE β (−ω, ω, 0). The PDTP-based organic dye (MC28) is selected to serve as a reference, and the quantum chemical models of its ten derivatives (SLN1-SLN10) are constructed by incorporating a variety of previously reported π-linkers into the reference. DFT and TD-DFT calculations reveal that π-linker modification tunes the NLO characteristics in SLN1-SLN10. The photophysical, electronic aspects, molecular electrostatic potential (MEP), frontier molecular orbital (FMO), density of state (DOS), transition density matrix (TDM), natural population analysis (NPA), and frequency-dependent NLO response properties of investigated dyes were evaluated. Giant NLO responses due to a much lower energy gap than the reference dye was found in SLN1-SLN10 confirmed by FMO analysis. UV–Vis analysis determined that the maximum absorption wavelength of the studied dyes was in the visible spectrum (383–413 nm). The proposed dye’s active NLO sensitivity and charge separation state was shown to have resulted from the migration of electrons from D to A via π-linkers using natural population analysis (NPA) analysis. In addition, molecular electrostatic potential (ESP), electron localization function (ELF), and localized orbital locator (LOL) topological assessments are carried out to evaluate the transfer of charge that takes place within SLN1-SLN10 as well as high NLO features. Maximum values of linear polarizability (αo) and first-hyperpolarizability (βo) were calculated to be 5.64 × 102 a.u. and 1.89 × 104 a.u., respectively in SLN3. At 1907.21 nm, SLN3 with terthiophene linker showed a remarkable SHG β(−2ω,ω,ω) and EOPE β (−ω,ω,0) response of 2.60 × 104 a.u. and 2.09 × 104 a.u. respectively. The theoretical structure provided conclusive evidence that the dyes under investigation possess excellent static and NLO potential at different laser wavelengths and should be considered for use in future NLO applications.

Methods Development and Validation for the Estimation of Pioglitazone HCl in Bulk and Formulations by UV Spectroscopy and FTIR

The use of spectroscopic analysis, particularly UV spectrophotometer, is a simple and essential technique for bulk drug estimation, formulation studies, and compatibility assessments of drugs with various excipients. In the pharmaceutical industry, various analytical instruments, including Fourier transform infrared spectroscopy (FTIR), are employed for investigating drug-excipient interactions that can impact the stability of active pharmaceutical ingredients. This study aimed to develop a UV spectrophotometric method for the analysis of Pioglitazone hydrochloride in phosphate buffer (pH 7.4) and methanolic solution, assessing its linearity and compliance with Beer's Law. Furthermore, we aimed to use FTIR to characterize potential interactions between Pioglitazone and common pharmaceutical excipients, such as Guar Gum, Chitosan, and Sodium Alginate. Standard solutions of Pioglitazone were prepared in phosphate buffer (pH 7.4) and methanol. UV spectrophotometer was conducted to determine the maximum absorption wavelength. Calibration curves were constructed to evaluate linearity and adherence to Beer's Law. FTIR analyses were performed to investigate drug-excipient interactions by examining the functional groups. In phosphate buffer (pH 7.4), the maximum absorption wavelength for Pioglitazone hydrochloride was 268 nm. The calibration curve for Pioglitazone in phosphate buffer (pH 7.4) demonstrated linearity in the concentration range of 1–20 µg/ml, with a correlation coefficient of 0.998. In methanol, the maximum absorption wavelength for Pioglitazone hydrochloride was found to be 272 nm. The calibration curve in methanol exhibited linearity in the range of 1–20 µg/ml, with a correlation coefficient of 0.999. FTIR analysis revealed potential drug-excipient interactions, particularly in the case of Guar Gum, Chitosan, and Sodium Alginate, suggesting the formation of stable hydrogen bonds. The developed UV spectrophotometric method for Pioglitazone analysis is a reliable, cost-effective, and reproducible approach, making it a valuable tool for drug development and quality control. Additionally, the FTIR characterization confirmed interactions between Pioglitazone and common pharmaceutical excipients, enhancing our understanding of formulation compatibility.

Role of extended end-capped acceptors in non-fullerene based compounds towards photovoltaic properties

Fullerene free organic solar cells (OSCs) have found at the forefront in the photovoltaic sector due to effective optical and electronic characteristics. The quantum chemical investigation focused on the designing of pentacyclic aromatic bislactam based chromophores for highly efficient OSCs. A series of eight molecules (PCLMD1–PCLMD8) was designed from reference compound (PCLMR), with A2–π–A1–π–D–π–A1–π–A2 configuration via end group redistribution with benzothiophene based acceptors. Through benchmark study of UV–Vis between simulated and experimental values of PCLMR, MPW1PW916-31G(d,p) functional was selected of DFT approach. Various analyses such as absorption properties (UV–Vis), frontier molecular orbitals analysis (FMOs), transition density matrix (TDM), open circuit voltage (Voc) and density of state (DOS) were performed in order to explore the photovoltaic properties of above-mentioned chromophores. Modification of peripheral acceptors brought about significant changes in their charge-transfer properties. These alterations resulted in reduced exciton binding energy (Eb) ranging from 2.277 to 2.087 eV, a narrower bandgap (Eg) ranging from 1.746 to 1.868 eV and an increased maximum absorption wavelength (λmax) ranging from 829 to 882 nm in the solvent phase. These values were observed in comparison to PCLMR, which had an Eb of 2.443 eV, an Eg of 1.895 eV and λmax at 813 nm. The FMO analysis indicated a significant charge distribution across HOMO-LUMO in the designed chromophores. Furthermore, the rates of electron and hole mobility as well as the open-circuit voltage (Voc) were higher for all the benzothiophene acceptor-based molecules (PCLMD1–PCLMD8) than that of PCLMR. The analysis showed that the integration of benzothiophene acceptors with electron-withdrawing groups amplifies charge transfer towards acceptor components, leading to heightened JSC and Voc values in organic solar cells (OSCs). This phenomenon is attributed to the decrease in the energy level of the lowest unoccupied molecular orbital (LUMO), while the highest occupied molecular orbital (HOMO) remains mostly unchanged, along with the effective broadening of the absorption spectrum. Hence, it can be concluded that by employing molecular engineering with benzothiophene acceptor moieties, the efficiency of photovoltaic materials based on NF compounds could be improved.