Fluorescence Spectral Analysis Research Articles

Chromite ore: X-ray fluorescence spectral analysis of Kβ and L-lines by WD-XRF

Chromite ore: X-ray fluorescence spectral analysis of Kβ and L-lines by WD-XRF

Structure, spectral properties and antioxidant activity of melanoidins extracted from high temperature sterilized lotus rhizome juice

Melanoidins are complex macromolecular compounds closely associated with the browning phenomenon in high-temperature sterilized lotus rhizome juice (HTSL). This study aimed to preliminarily investigate the structural properties of melanoidins extracted from HTSL. Results showed that the average molecular weight of HTSL melanoidins ranged from 1.48 to 41.40 kDa. Medium and high molecular weight melanoidins were the main contributors to the brown color of HTSL. Sugars, proteins, and phenolics were present in HTSL, among which sugar was the most abundant, with glucose being the predominant monosaccharide in acid degradation products of melanoidins. Through fluorescence and ultraviolet spectral analysis, we found that the melanoidins contained carboxyl and carbonyl compounds, as well as furan and pyran heterocyclic compounds. The infrared spectra and nuclear magnetic resonance spectra revealed a prominent sugar absorption peak, indicating that sugar was the main component of the melanoidins of HTSL. Furthermore, in vitro antioxidant experiments showed that the antioxidant activity of melanoidins was significantly positively correlated with phenolic compounds. Our results indicated that there were differences in the structural properties of melanoidins fractions with different molecular weights. MW-H fraction significantly impacted the color and antioxidant activity of HTSL.

Wavelet scattering transform and entropy features in fluorescence spectral signal analysis for cervical cancer diagnosis

Cervical cancer is a prevalent malignant tumor within the female reproductive system and is regarded as a prominent cause of female mortality on a global scale. Timely and precise detection of various phases of cervical cancer holds the potential to substantially enhance both the rate of successful treatment and the duration of patient survival. Fluorescence spectroscopy is a highly sensitive method for detecting the biochemical changes that arise during cancer progression. In our study, fluorescence spectral data is collected from a diverse group of 110 subjects. The potential of the scattering transform technique for the purpose of cancer detection is explored. The processed signal undergoes an initial decomposition into scattering coefficients using the wavelet scattering transform (WST). Subsequently, the scattering coefficients are subjected to computation for fuzzy entropy, dispersion entropy, phase entropy, and spectral entropy, for effectively characterizing the fluorescence spectral signals. These combined features generated through the proposed approach are then fed to 1D convolutional neural network (CNN) classifier to classify them into normal, pre-cancerous, and cancerous categories, thereby evaluating the effectiveness of the proposed methodology. We obtained mean classification accuracy of 97% using 5-fold cross-validation. This demonstrates the potential of combining WST and entropic features for analyzing fluorescence spectroscopy signals using 1D CNN classifier that enables early cancer detection in contrast to prevailing diagnostic methods.

Effect of 5-aminolevulinic acid-mediated photodynamic therapy against Fusobacterium nucleatum in periodontitis prevention

Periodontitis, a chronic infectious disease leading to gingival atrophy and potential tooth loss through alveolar bone resorption, is closely linked to the oral microbiome. Fusobacterium nucleatum, known to facilitate late-stage bacterial colonization in the oral microbiome, plays a crucial role in the onset of periodontitis. Controlling F. nucleatum abundance is vital for preventing and treating periodontal disease. Photodynamic therapy combined with 5-aminolevulinic acid (ALA-PDT) has been reported to be bactericidal against Pseudomonas aeruginosa and Staphylococcus aureus. We aimed to investigate the bactericidal potential of ALA-PDT against F. nucleatum, which was evaluated by examining the impact of varying 5-ALA concentrations, culture time, and light intensity. After ALA-PDT treatment, DNA was extracted from interdental plaque samples collected from 10 volunteers and sequenced using the Illumina MiSeq platform. To further elucidate the bactericidal mechanism of ALA-PDT, porphyrins were extracted from F. nucleatum following cultivation with 5-ALA and subsequently analyzed using fluorescence spectra. ALA-PDT showed a significant bactericidal effect against F. nucleatum. Its bactericidal activity demonstrated a positive correlation with culture time and light intensity. Microbiota analysis revealed no significant alteration in α-diversity within the ALA-PDT group, although there was a noteworthy reduction in the proportion of the genus Fusobacterium. Furthermore, fluorescence spectral analysis indicated that F. nucleatum produced an excitable photosensitive substance following the addition of 5-ALA. Overall, if further studies confirm these results, this combined therapy could be an effective strategy for reducing the prevalence of periodontitis.

The impact of pressure-shift freezing on the three-dimensional network structure and properties of myofibrillar proteins in surimi gel derived from freshwater fish

Freezing treatment can prolong the shelf life of surimi products, but it will lead to deterioration of surimi gel quality. This study compared the effects of three different processing methods — non-freezing processing (control), conventional air freezing (CAF), and pressure-shift freezing (PSF) — on the three-dimensional (3D) network structure of grass carp surimi gel. After PSF treatment, the pores in the 3D gel network structure were denser compared to the control group which facilitates interaction of water and network structure. Furthermore, the ultraviolet and fluorescence spectral analysis indicated that PSF treatment mitigates the decline in stability of the tertiary structure of myofibrillar protein (MP) during freezing. The microstructure of MP showed that PSF treatment promotes the cross-linking of MP to form protein aggregates and then promotes the gelation of MP. Industrial relevancePSF can increase the commodity value of low-value freshwater fish products and has potential in the development of new products of surimi gels. This study reported a novel idea and theoretical basis for the application of PSF technology in the frozen food and aquatic product processing industry.

Potential application of body fluids autofluorescence in the non-invasive diagnosis of endometrial cancer.

Endometrial carcinoma (EC) is the most common cancer of the female reproductive tract in developed countries. The prognosis and 5-year survival rates are closely tied to the stage diagnosis. Current routine diagnostic methods of EC are either lacking specificity or are uncomfortable, invasive and painful for the patient. As of now, the gold diagnostic standard is endometrial biopsy. Early and non-invasive diagnosis of EC requires the identification of new biomarkers of disease and a screening test applicable to routine laboratory diagnostics. The application of untargeted metabolomics combined with artificial intelligence and biostatistics tools has the potential to qualitatively and quantitatively represent the metabolome, but its introduction into routine diagnostics is currently unrealistic due to the financial, time and interpretation challenges. Fluorescence spectral analysis of body fluids utilizes autofluorescence of certain metabolites to define the composition of the metabolome under physiological conditions. This review highlights the potential of fluorescence spectroscopy in the early detection of EC. Data obtained by three-dimensional fluorescence spectroscopy define the quantitative and qualitative composition of the complex fluorescent metabolome and are useful for identifying biochemical metabolic changes associated with endometrial carcinogenesis. Autofluorescence of biological fluids has the prospect of providing new molecular markers of EC. By integrating machine learning and artificial intelligence algorithms in the data analysis of the fluorescent metabolome, this technique has great potential to be implemented in routine laboratory diagnostics.

2D Copper–Porphyrin Metal–Organic Framework Nanosheet‐Photosensitized TiO2 for Efficiently Broadband Light‐Driven Conversion of CO2 to CH4

The effective utilization of light is crucial in the use of the solar energy for CO2 conversion into valuable fuels and chemicals, in which improving the photocatalytic materials’ capacity to absorb light is a key. Herein, a 2D copper–porphyrin metal−organic framework (MOF)‐photosensitized titania, TiO2/Zn–CuTCPP, is reported, which can absorb wide range of light and photoreduce CO2 with high efficiency under full spectrum irradiation. Fluorescence spectral analysis elucidates the relationship between the photocatalytic activity and the electron–hole separation efficiency. In addition, mechanistic information obtained from electron paramagnetic resonance and in situ infrared analyses demonstrates that the presence of Cu–N4 site in the MOF structure is conducive to the generation of hydrogen free radicals (•H), which plays a key role in the formation of intermediates, thus facilitating the hydrogenation in the reaction process. Consequently, TiO2/Zn–CuTCPP significantly enhances the photocatalytic conversion of CO2 into CH4 with a yield 14 times higher than that of P25.

ИССЛЕДОВАНИЕ ФИЗИКО-ХИМИЧЕСКИХ И ПРОТИВОИЗНОСНЫХ СВОЙСТВ МОТОРНЫХ МАСЕЛ ПО ЗАВЕРШЕНИИ ПРОЦЕССА ЭКСПЛУАТАЦИИ

There is given the study of viscous properties of engine oil, depending on the temperature before and after change on modern domestic gasoline and diesel cars, the determination of spectral characteristics and X-ray fluorescence analysis of wear particles after mileage. The degree of viscosity of semi-synthetic oils of two types is estimated. The oils were cooled and heated up to 150 °C. A digital viscometer was used, the dynamic viscosity of all oils decreased with increasing temperature, which is associated with oxidation in waste oil. To assess the effect of motor oil on engine operation, IR spectrometric analysis is performed and the thickness of the lubricating film is determined. The test results showed a qualitative and quantitative change in the characteristic frequencies of the new engine oil and the spent one after 10,000 km. X-ray fluorescence analysis makes it possible to analyze wear products and determine which mechanism in the engine is most susceptible to wear. Lines have characteristic absorption frequencies and indicate a change in physico-chemical properties of oil in the engine. An increase in contamination and in the viscosity of used oils is associated with the presence of impurities formed during the oxidation and polymerization of the base oil. It is necessary to increase the number of samples and sampling during different periods of operation so that you can verify the same effect throughout the entire engine operation. The results obtained indicate that these methods can be used to analyze and control the mode of operation of oils in the engine, allowing to determine the wear and further apply appropriate additives to the oil to improve performance properties.

Fluorescence spectral analysis and logistic regression modeling for diagnosing basal cell carcinoma on head and neck

The optical fluorescence method is distinguished by key features such as non-invasiveness, high sensitivity, and resolution, which are superior to traditional diagnostic approaches. Unlike histopathological examinations and biochemical analyses, optical diagnostic methods obviate the need for tissue sampling, enabling the analysis of virtually unlimited material.The research aims to examine the effectiveness of emission spectra analysis in the diagnosis of basal cell carcinoma (BCC) of the scalp and neck. The analysis was based on data provided by Specialized Hospital No. 2 in Bytom comprising a study sample of 10 patients. For each patient, fluorescence emission spectra were recorded from each of 512 points along a 5 mm line.The results obtained from the histopathological examination, the analysis and morphological evaluation of the tissue, and the diagnosis through microscopic observation were used to define a dichotomous variable (presence or absence of a cancerous lesion), adopted in the study as the modeled variable. The next step of the presented study involved constructing a logistic regression model for identifying cancerous lesions depending on the biochemical indicator's relative fluorescence value (RFV) and emission wavelength (ELW) within the 620 nm to 730 nm range. This wavelength range is often used in fluorescence diagnostics to detect various pathologies, including cancerous lesions.The resulting binary logistic regression model, logit(p)=−33.17+0.04ELW+0.01RFV, indicates a statistically significant relationship between wavelength and relative fluorescence values with the probability of detecting cancer. The estimated model exhibits a good fit and high predictive accuracy. The overall model accuracy is 84.8 %, with the correct classification rates at approximately 96 % for healthy individuals and 74 % for individuals with cancer. These findings underscore the potential of photodynamic diagnostics in cancer detection and monitoring.

Development of a technique for X-ray fluorescence analysis of zinc-aluminum-magnesium alloys

A technique for X-ray fluorescence spectral analysis of zinc-aluminum- magnesium alloys has been developed, which allows the determination of Mg, Al, Pb, Si, Cu, Mn, Fe, Ni content in the alloy. The effect of the sample preparation method on the linearity of calibration graphs is revealed. The conditions for determining the main alloying (Al, Mg) and impurity (Pb, Fe, Cu, Si, Mn, Ni) elements by X-ray fluorescence spectrometry were studied. It is proposed to use the correction of the matrix effect by selecting alpha coefficients for the intensity of X- ray radiation with subsequent automatic conversion of the function into a linear form. Calibration graphs for determination of the elements in the corresponding ranges, i.e., Mg (0.00019 – 5.04%), Al (0.0002 – 12.4%), Pb (0.0012 – 2.07%), Si (0.0005 – 0.12%), Cu (0.0006 – 5.95%), Mn (0.0004 – 0.00524%), Fe (0.0009 – 0.41%), Ni (0.0009 – 0.27%), were obtained using standard reference samples and production samples of the alloys, the chemical composition of which was previously determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The correctness of the developed methodology was confirmed by analysis of standard samples and comparative analysis of the obtained results using the Student’s t-test.

METHODS FOR STUDYING THE CHEMICAL COMPOSITION OF PRODUCTS FROM NON-FERROUS METALS OF THE X–XVIII CENTURIES FROM THE TERRITORY OF NORTH AND CENTRAL BELARUS

The article provides an overview of modern methods for studying the chemical composition of products made of non-ferrous metals of the X–XVIII centuries. It has been established that the main methods for studying the elemental composition of archaeological non-ferrous metals are laser emission spectral analysis, optical emission spectral analysis and X-ray fluorescence spectral analysis. It is noted that the most suitable for studying products made of non-ferrous metals are the X–XVIII centuries should be considered standard-free X-ray fluorescence spectral analysis, which allows obtaining quantitative and qualitative data in real time, does not require preliminary sample preparation and does not leave traces on the surface of artifacts. As a result of the author’s analysis of the statistical error in determining the main components of copper-based alloys using the Student’s t-test, it was established that the data obtained during research in different laboratories using different methods are comparable and can be used to study the characteristics of non-ferrous metalworking in the Northern and Central Belarus in the X–XVIII centuries.

Dissolved organic matter promoted hydroxyl radical formation and phenanthrene attenuation during oxygenation of iron-pillared montmorillonites

The oxygenation of Fe(II)-bearing minerals for hydroxyl radicals (HO•) formation and contaminant attenuation receives increasing attentions. However, information on dissolved organic matter (DOM) with different types, concentrations, and molecular weights (MWs) in manipulating HO• formation and contaminant attenuation during mineral oxygenation remain unclear. In this study, four iron-pillared montmorillonites (IPMs) and two DOM samples [e.g., humic acids (HA) and fulvic acids (FA)] were prepared to explore the HO• formation and phenanthrene attenuation during the oxygenation of IPMs in the presence or absence of DOMs. Results showed that iron-pillared and high-temperature calcination procedures extended the interlayer domain of IPMs, which provided favorable conditions for a high HO• production from 1293 to 14537 μmol kg−1. The surface-absorbed/low crystalline Fe(Ⅱ) was the predominant Fe(Ⅱ) fractionations for HO• production, and presence of DOMs significantly enhanced the HO• production and phenanthrene attenuation. Moreover, regardless of the types and concentrations, the low MW (LMW, <1 kDa) fraction within DOM pool contributed highest to HO• production and phenanthrene attenuation, followed by the bulk and high MW (HMW-, 1 kDa∼0.45 μm) fractions, and FA exhibited more efficient effects in promoting HO• production and phenanthrene attenuation than HA. The fluorescent spectral analysis further revealed that phenolic-like fluorophores in LMW-fraction were the main substances responsible for the enhanced HO• production and phenanthrene attenuation. The results deepen our understandings toward the behaviors and fate of aquatic HO• and contaminants, and also provide technical guidance for the remediation of contaminated environments.

Crystal growth and vibrational spectroscopic studies on the novel NLO active 2-amino-4-methylpyridinium fluoroborate single crystal by experimental and computational technique

A semi-organic non-linear optical (NLO) single crystal of 2-amino-4-methylpyridinum fluoroborate(2AFB) to be synthesized and characterized via single crystal X-ray diffraction technique (SXRD), UV–Vis, FTIR and FT-Raman spectra. The quantum chemical calculations were carried out using density functional method (DFT) with B3LYP/6–31+G(D) basis set. The intermolecular interaction and stability of the title molecule have been obtained by NBO analysis. The molecular electrostatic potential and frontier molecular orbital analysis give a visual representation of charge distribution of the title molecule. The N-H…F interaction within 2AFB molecule was investigated via AIM and RDG analysis. The optical quality and energy band gap of 2AFB single crystal were found out using UV–visible spectral analysis. The emission spectra of the grown 2AFB single crystal has been examined by fluorescence spectral analysis. 2D fingerprint plot confirms the H…F and H…H interactions that exhibit the most significant contribution in crystal packing. The outcome of SXRD, UV-visible, HOMO-LUMO, NLO and Z-scan values were compared with earlier reported compounds and amongst which the analysed compound 2AFB shows good NLO activity. The NLO activity of the title molecule was confirmed theoretically and experimentally by DFT method and Z-scan technique.

Fluorescent Eu-MOF@nanocellulose-based nanopaper for rapid and sensitive detection of uranium (Ⅵ)

Radioactive uranium leaks into natural water bodies mainly in the form of uranyl ions (UO22+), posing ecological and human health risks. Fluorescent europium-based metal-organic frameworks (Eu-MOFs) have been demonstrated to be effective fluorescent sensors for UO22+, but the large size, powder state and poor dispersity limit their further application. In this work, fluorescent Eu-MOFs were in-situ grown on TEMPO-oxidized cellulose nanofibers (TOCNFs), which is the first time that spherical Eu-MOF crystals with sizes below 10 nm were prepared. Fluorescence spectral analysis revealed a nine-fold increase in the fluorescence intensity of TOCNF@Eu-MOF compared to Eu-MOF. The nanocomposites achieved rapid and sensitive fluorescence quenching to UO22+ through the “antenna effect” and unsaturated Lewis basic sites on the ligands binding with UO22+. Moreover, TOCNF@Eu-MOF demonstrated excellent selectivity and anti-interference for UO22+ detection. For the nanopaper-based sensor made from TOCNF@Eu-MOF, the Stern-Volmer quenching constant (KSV) was calculated as 8.21 × 104 M−1, and the lowest limit of detection (LOD) was 6.6 × 10−7 M, significantly lower than the 1.32 × 10−6 M of Eu-MOFs. In addition, the nanopaper exhibited good fluorescence stability and cyclic detection performance, enabling the rapid and convenient detection of UO22+ in the aqueous phase within 30 s by simple dipping.

Targeted spectroscopy in the eye fundus.

The assessment of biomarkers in the eye is rapidly gaining traction for the screening, diagnosis, and monitoring of ocular and neurological diseases. Targeted ocular spectroscopy is a technology that enables concurrent imaging of the eye fundus and analysis of high-quality spectra from a targeted region within the imaged area. This provides structural, compositional, and functional information of specific regions of the eye fundus from a non-invasive approach to ocular biomarker detection. The aim of our study was to demonstrate the multimodal functionality and validation of targeted ocular spectroscopy. This was done in vitro, using a reference target and a model eye, and in vivo. Images and spectra from different regions of a reference target and a model eye were acquired and analyzed to validate the system. Targeted ocular fluorescence spectroscopy was also demonstrated with the same model. Subsequently, in vivo imaging and diffuse reflectance spectra were acquired to assess blood oxygen saturation in the optic nerve head and the parafovea of healthy subjects. Tests conducted with the reference target showed accurate spectral analysis within specific areas of the imaging space. In the model eye, distinct spectral signatures were observed for the optic disc, blood vessels, the retina, and the macula, consistent with the variations in tissue composition and functions between these regions. An ocular oximetry algorithm was applied to in vivo spectra from the optic nerve head and parafovea of healthy patients, showing significant differences in blood oxygen saturation. Finally, targeted fluorescence spectral analysis was performed in vitro. Diffuse reflectance and fluorescence spectroscopy in specific regions of the eye fundus open the door to a whole new range of monitoring and diagnostic capabilities, from assessment of oxygenation in glaucoma and diabetic retinopathy to photo-oxidation and photodegradation in age-related macular degeneration.

Integrated Broadband Filter with Sharp Transition Edges Based on SiN and SiON Composite Waveguide Coupler

Broadband filters with sharp transition edges are important elements in diverse applications, including Raman and fluorescence spectral analysis, wideband wavelength-division multiplexing (WDM), and multi-octave interferometry. While the multi-layer thin-film interference broadband filter has been widely applied in various free-space optical systems, its integrated counterpart is still far from mature, which is also highly desired for constructing chip-scale miniature optical modules. In this article, we design, fabricate, and characterize an integrated broadband filter with sharp transition edges. An adiabatic coupler based on silicon nitride (SiN) and silicon oxynitride (SiON) composite waveguide is employed here. Long-pass, short-pass, band-pass, and band-stop filters can be realized in a single design of the composite waveguide coupler for a specific wavelength range, with only a difference in the SiN taper waveguide width. Experimental results with a roll-off value of larger than 0.7 dB nm−1 and a 15 dB extinction ratio (ER) are presented.

High-performance luminescence of europium ion-activated Na2O-CaO-SiO2 system glass-ceramics through component regulation and crystallization process optimization strategies

Luminescent glass-ceramics has garnered significant attention within the research community owing to its exceptional characteristics, including robust chemical stability, outstanding thermal stability, and efficient thermal conductivity. However, persistent challenges include issues related to suboptimal luminous efficiency and color rendering index. In the context of this research endeavor, we have achieved a noteworthy achievement by successfully fabricating a novel variant of glass-ceramics doped with both Eu2+ and Eu3+ ions within the Na2O-CaO-SiO2 system glass. This innovative glass-ceramics composition encompassed Na4Ca4Si6O18 crystals, characterized by grain sizes <110 nm. Our investigations, featuring comprehensive optical spectra analysis and detailed morphological examinations, have provided substantial evidence indicating the preferential occupation of Eu3+ ions in the Ca2+ sites residing within the Na4Ca4Si6O18 crystal lattice, conversely, it is possible that the distribution of Eu2+ ions occurred within the glass matrix. Additionally, it is worth noting that this glass-ceramic material demonstrated a heightened excitation efficiency when subjected to 464 nm blue light, surpassing its performance with 393 nm violet light. Detailed fluorescence spectral analysis unveiled the impressive internal quantum efficiency of the glass-ceramics, reaching an impressive 80.27%, and this glass-ceramics exhibited remarkable fluorescence thermal stability at 150 °C, preserving approximately ∼75% of its luminescent intensity at room temperature. Furthermore, we have encapsulated the white light-emitting diode (W-LED) device, integrated with a 460 nm LED chip, optimized glass-ceramics, and YAG: Ce3+ phosphor. The outcomes were characterized by the warm white-light emission, suitable chromaticity coordinates, a high color rendering index (approximately 85.4), and impressive luminous efficiency (up to 112.47 lm/W). In summary, these findings unequivocally underscore the substantial potential of glass-ceramics in the realm of high-power W-LED lighting applications.

Exploring linear and nonlinear optical behaviour of morpholine p-nitrophenol crystal: Computational and experimental analysis

Optically good quality morpholine p-nitrophenol (MPN) crystal was effectively grown from a slow evaporation technique. Unit cell parameters of MPN were estimated by single crystal X-ray diffraction and it crystallizes in the P21/c space group. The existence of several functional groups in MPN is established by FTIR analysis. UV–vis-NIR spectroscopy inspected the lower cut-off wavelength and band gap energy of MPN. A fluorescence spectral analysis of MPN was carried out. Experimental and computational calculations of nonlinear optical activity have been studied. The second harmonic generation of MPN is 1.9 times greater than the reference KDP material. Using the Z-scan approach, the grown crystal's third-order NLO susceptibility (χ3) was determined. The laser damage threshold of MPN crystal is studied and it is estimated as 5.12 GW/cm2. The highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) and molecular tying-up explorations were executed. Ground state enhanced geometry and molecular electrostatic potential (MEP) were analysed.

Photo and spectral fluorescence analysis of the spinal cord injury area in animal models

The purpose of the work is to follow the dynamics of changes in fluorescent signals in the near-surface layers of tissue of injured areas of the back of laboratory animals, which will allow, by indirect evidence, to evaluate the information content of fluorescence diagnosis for subsequent possible diagnostic monitoring of photodynamic therapy of the spinal cord. The model animals were Wistar rats. Two types of contusions were modeled: pneumo-contusion and contusion by a falling load. Methylene blue and indocyanine green were used as photosensitizers. Fluorescence measurements were carried out by imaging and spectrometric methods. A stroboscopic fluorescence imager with an excitation wavelength of 630 nm was used to acquire fluorescence images. The LESA-01-BIOSPEC spectrometer with a He-Ne laser excitation allowed to obtain spectra. It was shown that both methods make it possible to estimate the fluorescence value of methylene blue and indocyanine green in the tissues under study. Moreover, the photographic method also allows to obtain the spatial distribution of fluorescence. The general trend found in the data is a more intense and uniform fluorescence of the dorsal region of rats with methylene blue and a less intense, but more contrasting distribution of indocyanine green. The presented methods are non-invasive, which makes them attractive for diagnostic use. However, due to the shallow depth of signal reception, the condition of the spine can be determined only indirectly, by the condition of the near-surface layers of tissue that accumulate the photosensitizer.

Synthesis, characterization, DFT, vibrational analysis (FT-IR and FT-Raman), topology and molecular docking studies of 3,3′-((1E,1′E)-((sulfonylbis(4,1-phenylene)) bis (azaneylylidene)) bis (methaneylylidene)) diphenol

The 3,3′-((1E,1′E)-((sulfonylbis(4,1-phenylene)) bis (azaneylylidene)) bis (methaneylylidene)) diphenol (D3H) was characterized by experimental and theoretical approaches. Titled compound FT-IR, FT-Raman, NMR (1H), UV–vis and fluorescence spectral analysis were developed in experimentally. After that, theoretical computations at the DFT/WB97XD/cc-pVDZ basis set level were carried out. The experimental geometrical parameters and the theoretical geometrical parameters were compared and well matched. The frequencies calculated using FT-Raman and FT-IR matched those obtained from experiments. The potential energy distributions analysis was calculated. Comparisons were made between the theoretical and experimental NMR chemical shifts. Absorption wavelengths in the UV–Vis spectrum were measured experimentally and compared to those predicted by TD-DFT. It is optical material, because its showed good fluorescence spectrum. The frontier molecular orbital, natural bond orbital analysis, molecular electrostatic potential, electron localized function, reduced density gradient and localized orbital locator, were carried out and thoroughly explained. According on the results of docking tests, the greatest possible binding energy score is -7.52 kcal/mol.