Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy最新文献

{"title":"Observation of reversible conformational interconversion accompanied by 3p internal conversions in Rydberg-excited N,N-dimethylethylamine","authors":"","doi":"10.1016/j.saa.2024.125279","DOIUrl":"10.1016/j.saa.2024.125279","url":null,"abstract":"<div><div>Conformational dynamics has been well observed in the 3s Rydberg state of amines, whereas its observation in higher-energy, non-equilibrium 3p Rydberg states is very rare, especially for a reversible conformational transition that could compete with other non-adiabatic transitions. Herein, we report the observation of a reversible conformational interconversion phenomenon in the 3p Rydberg excited-state dynamics of N,N-dimethylethylamine (DMEA). Upon electronic excitation, a forward and backward interconversion between the initially prepared 3p_l and 3p_h conformers accompanied by 3p internal conversions occurs, resulting in a 3p_l/3p_h equilibrium ratio of 61 %/39 % within ∼1.5 ps. The ensuing parallel internal conversions from the 3p_l to 3s_l and 3p_h to 3s_h deposit about 1.80 eV of vibrational energy into the 3s state, enabling a fast conformational interconversion between the 3s_h and 3s_l conformers to proceed within ∼2.0 ps. The final 3s_l/3s_h equilibrium ratio was determined to be 76 %/24 %. This work presents a real-time observation of the entire conformational interconversion process initiating from the higher-energy 3p states and finally reaching an equilibrium on the lower-energy 3s state.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of chlorine in potassium chloride and potassium sulfate using chemical imaging and artificial neural network","authors":"","doi":"10.1016/j.saa.2024.125253","DOIUrl":"10.1016/j.saa.2024.125253","url":null,"abstract":"<div><div>Chlorine in potassium chloride and potassium sulfate must be detected due to its negative effect on soil. Although the laboratory-based chlorine measurement tests are reliable, they are time-consuming, expensive, and requires chemical agents and highly skilled operators. Therefore, the novelty of the present research is developing a fast, accurate, and cheap machine-based method to measure the amount of chlorine. The purpose of this research was to apply hyperspectral imaging and machine learning techniques to detect chlorine content in potassium chloride and potassium sulfate. Different percentages of chlorine in potassium chloride and potassium sulfate products were prepared with ranges of 53.1–50.05 and 1.47–2.13 %, respectively. Hyperspectral images were captured from the sample at the range of 400–950 nm. Mean, minimum, maximum, median, variance, and standard deviation features were extracted from the image channels corresponding to the effective wavelengths. The extracted features were classified using artificial neural network method and highest accuracy of the best models for potassium chloride and potassium sulfate were 95.6 and 94.4, respectively. The combination of hyperspectral imaging and machine learning promises reliable detection of chlorine content in potassium chloride and potassium sulfate in industrial systems with high speed and low cost.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cydonia oblonga extract mediated biosynthesis of gold nanoparticles: Analysis of its anti-oral cancer and antioxidant properties","authors":"","doi":"10.1016/j.saa.2024.125268","DOIUrl":"10.1016/j.saa.2024.125268","url":null,"abstract":"<div><div>Here, using natural and biological macromolecules derived from <em>Cydonia oblonga</em> extract, we have developed a green protocol for the biogenic made Au NPs. Under ultrasonic activated conditions, the <em>Cydonia oblonga</em> phytomolecules were employed as an efficient green reducing agent for the Au³⁺ ions to the Au⁰ NPs. Additionally, by encapsulating or capping, they allowed the Au NPs to stabilize on their own. Several physicochemical techniques, such as elemental mapping, TEM, FE-SEM, UV–Vis spectroscopy, EDS, and ICP-OES, were used to analyze the structure of the Au NPs/<em>Cydonia oblonga</em> bio-nanocomposite. The field of medicinal therapeutics pertaining to human health includes cancer treatment as a major component. Subsequently, the as prepared Au NPs/<em>Cydonia oblonga</em> bio-nanocomposite was investigated for antioxidant and human anti-oral cancer assays. In such studies a number of cell lines, viz., HSC-3, HSC-2, and Ca9-22 were used in determining the cytotoxicity. Notably, Au NPs/<em>Cydonia oblonga</em> exhibit significant anti-oral cancer properties against HSC-3, HSC-2, and Ca9-22 cancer cell lines following time and dose-dependent manner. The corresponding IC₅₀ values were determined as 201, 192, and 246 µg/mL respectively. DPPH radical scavenging method was used to determine the antioxidant activity of Au NPs/<em>Cydonia oblonga</em> bio-nanocomposite. The significant IC₅₀ value suggested the material having very good antioxidant potential. The anti-human oral cancer effect of our material is believed to be due to its antioxidant effects.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluorescence detection of adenosine triphosphate based on dimeric G-quadruplex","authors":"","doi":"10.1016/j.saa.2024.125267","DOIUrl":"10.1016/j.saa.2024.125267","url":null,"abstract":"<div><div>Adenosine triphosphate (ATP) is a major chemical energy carrier in organisms and is involved in numerous biological processes. ATP levels are associated with many diseases, cell viability, and food freshness. Thus, it has become an important biomarker. Many strategies have been used to detect ATP. However, the problems of difficult-to-prepare materials, too much dependence on instruments, and complicated processes restrict the application of these methods. In this study, we proposed a novel ATP detection sensor. The method is based on the fluorescence enhancement effect of dimeric G-quadruplex (Di-G4) on thioflavin T (ThT). First, the cleavage of Di-G4 by S1 nuclease decreases system fluorescence. However, it can be recovered by increases in ATP concentrations, which act as an inhibitor of S1 nuclease. Under the optimized conditions, a good linear relationship was observed between fluorescence intensity and ATP concentrations within the range of 0.5–120 µM. The detection limit was 245 nM. The method was utilized to measure the ATP content in apples and compared with ATP assay kits, resulting in satisfactory results.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"β-galactosidase-activated red fluorescent probe assists in the diagnosis of pancreatitis","authors":"","doi":"10.1016/j.saa.2024.125265","DOIUrl":"10.1016/j.saa.2024.125265","url":null,"abstract":"<div><div>Acute pancreatitis (AP) is an acute inflammatory disease resulting from abnormal digestion of itself and surrounding organs by pancreatic enzymes caused by a variety of pathogenic factors. When the tissue of a biological organism is afflicted with pancreatitis and experiences swelling, bleeding, and necrotic injuries, the abnormal expression of β-galactosidase (β-Gal) activity becomes one of the main indicators for assisting in the diagnosis of pancreatitis. In this study, a highly specific red fluorescent probe designed for the detection of β-Gal activity has been developed. β-galactoside is used as the enzyme activating group, and the long-wavelength luminescent water-soluble organic molecule NBDOH is used as the luminophore to construct the fluorescent probe <strong>NBD-gal</strong>. <strong>NBD-gal</strong> is activated by abnormally overexpressed β-Gal, releasing a strong red fluorescent signal. The new fluorescent probe developed in this study is used to assist in the diagnosis of pancreatitis by detecting abnormal expression of β-Gal activity in vivo. In in vivo imaging experiments, <strong>NBD-gal</strong> can effectively differentiate between normal nude mice and pancreatitis nude mice. In addition, <strong>NBD-gal</strong> can be effectively localized in real-time to the pancreas and intestines, which are rich in β-Gal in nude mice. Therefore, <strong>NBD-gal</strong> exerts great potential in the early diagnosis, treatment, and prevention of biomedical clinical pancreatitis.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ancient and modern bone diagnosis: Towards a better understanding of chemical and structural feature alterations","authors":"","doi":"10.1016/j.saa.2024.125259","DOIUrl":"10.1016/j.saa.2024.125259","url":null,"abstract":"<div><div>Chemical and structural alterations hold great importance in the field of diagenesis. Attenuated Total Reflectance − Fourier Transform Infrared Spectroscopy (ATR-FTIR) is a valuable method for examining bio-apatite composition changes. Infrared spectroscopy (IR) and X-ray diffraction (XRD) were employed to analyze both modern and archaeological bone specimens. Organic and mineral component changes in modern and ancient samples were investigated. Ancient bone samples were collected from two archaeological sites in Jordan, dating back to the Iron and Byzantine ages. IR results indicated that collagen cross-links and mineral maturity are higher in modern bones compared to ancient bones. Additionally, the crystallinity index is higher in modern bones than in archaeological bones, while the carbonate to phosphate ratio (C/P) is lower in modern bones than in ancient ones. Curve fitting was applied to reveal the carbonate substitution inside the hydroxyapatite lattice within the IR region from 850 to 890 cm⁻¹. A2-type carbonates (identified as υ2 of CO₃²⁻) denote hydroxyl site substitution, and B-type carbonates represent a substitution to the phosphate site. The full width at half maximum (FWHM) of the peak at 604 cm⁻¹ from IR spectra reveals that crystallinity is higher in modern bones, as confirmed by the FWHM of the (002)-apatite pattern in XRD. Statistical analysis was conducted to validate these findings, ensuring the robustness of the results. Finally, the results obtained in this investigation align with previous literature reports regarding ATR-FTIR ratios. This suggests that modern bones have better crystallinity compared to ancient bones. Furthermore, the ATR-FTIR ratios indicate that the hydroxyl and phosphate sites of modern bones undergo more substitution than older bones. The findings of this study not only enhance our understanding of the diagnostic processes in archaeological bone specimens but also have broader implications for fields such as archaeology, anthropology, and forensics, where the analysis of bone composition and structural changes can provide valuable insights into the history and characteristics of ancient remains.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of phenolics in the analysis of virgin olive oil using near infrared spectroscopy","authors":"","doi":"10.1016/j.saa.2024.125262","DOIUrl":"10.1016/j.saa.2024.125262","url":null,"abstract":"<div><div>Olive oil is an indispensable part of the diet in Mediterranean regions, and is appreciated worldwide for its sensory characteristics, combining a fine aroma and pleasant flavor with the high nutritional value of specific chemical compounds. However, making rapid measurements of phenolic compounds is a major challenge for the olive oil sector. The development of a new method based on near infrared (NIR) spectroscopy may be considered an important advance for the sector, as it is rapid, low-cost, non-contaminant and non-destructive. In this study, three different NIR instruments – one FT-NIR benchtop instrument (671.82–2702.70 nm) and two low-cost portable devices (900–1700 nm and 1350–2150 nm) – were used to analyze a collection of virgin olive oil samples from various Mediterranean regions. To predict both the individual and total concentration of phenols in the olive oil, four signal pretreatment methods and modified partial least squares regression analyses were employed to develop the predictive models. The results showed that the benchtop FT-NIR instrument performed better than the other portable instruments when measuring the phenolic compounds in virgin olive oil. The best models of hydroxytyrosol derivatives, tyrosol derivatives, total phenols and “EFSA phenols” showed R²_cv values of 0.84, 0.85, 0.88 and 0.89, while the RPD_cv values were 2.51, 2.61, 2.93 and 2.95, respectively. Meanwhile, for the portable NIR instruments, the prediction models for hydroxytyrosol derivatives, total phenols and “EFSA phenols” (the sum of the hydroxityrosol and tyrosol derivatives) showed R²_cv values ranging between 0.75 and 0.81 and an RPD_cv between 2 and 2.5. These results indicate the great potential of NIR, both with benchtop and portable devices, to detect phenolic compounds in virgin olive oil, which can guarantee the quality of virgin olive oil and thus aid progress in the olive oil industry. Moreover, this is the first published work to determine phenolic compounds in virgin olive oil using portable NIR instruments.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of cigarettes with different grades by using FTIR microspectroscopy","authors":"","doi":"10.1016/j.saa.2024.125249","DOIUrl":"10.1016/j.saa.2024.125249","url":null,"abstract":"<div><div>In this paper, FTIR microspectroscopy was used to identify the cigarettes of three different grades such as Jinwan cigarettes (J group), Yinxiangyipin cigarettes (Y group) and Hongsanhuan cigarettes (H group). IR spectra and peak-area ratios (A₂₉₂₃ /A₈₁₆, A₁₆₀₁ /A₂₉₂₃, A₁₆₀₁/A₉₂₀ and A₁₀₇₂/A₈₁₆) revealed significant differences among H, Y and J groups, reflecting the changes in chemical compositions with increased grade. Discriminant analysis was carried out on basis of the above peak-area ratios, achieving 100% accuracy for identification of H, Y and J groups. Principal component analysis (PCA) showed that carbohydrates and proteins were closely related to the quality of the cigarettes. In addition, curve fitting further confirmed that the structure of carbohydrates underwent changes due to the quality of the cigarettes. The above results suggest that FTIR microspectroscopy can identify different grades of the cigarettes, which may be helpful for tobacco research.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142402535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective methane decomposition using spark discharge assisted laser-induced plasma: An approach based on Fourier transform infrared (FTIR) spectroscopy","authors":"","doi":"10.1016/j.saa.2024.125257","DOIUrl":"10.1016/j.saa.2024.125257","url":null,"abstract":"<div><div>The widespread utilization of fossil fuels cause to significantly elevate greenhouse gas emissions. Consequently, the developments of the innovative methods are essential to convert methane into the green energy. Recently, significant effort is made to enhance the performance of the plasma-based conversion technologies. Here, the dissociation rate of methane into heavier hydrocarbon compounds are carefully determined by making use of a hybrid laser-induced plasma (LIP) and spark discharge (SD). Fourier-transform infrared (FTIR) spectroscopy reveals a couple of characteristic peaks after laser triggering, whose intensities notably increase at higher applied voltages. The corresponding peaks indicate the formation of heavier compounds including <em>sp</em> and <em>sp²</em> C–H stretching bonds. The findings elucidate that the methane decomposition rate notably elevates in favor of hybrid SD-LIP against that of traditional LIP. It is worth noting that the simultaneous ablative effect of the catalyst surface to remove the carbon soot by the successive laser shots could prevent the catalytic deactivation leading to the sustained performance.</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the molecular interaction between apraclonidine, an α2-adrenergic receptor agonist, and bovine serum albumin using fluorescence and molecular docking techniques","authors":"","doi":"10.1016/j.saa.2024.125246","DOIUrl":"10.1016/j.saa.2024.125246","url":null,"abstract":"<div><div>Apraclonidine (APR) is a potent and selective α2-adrenergic receptor agonist used in the diagnosis of Horner’s Syndrome, and the residuals of APR that accumulate in tissues of animals can cause central nervous and cardiovascular systems influences in humans. Therefore, to understand the influence of APR on human health, we examined the interaction of APR with the carrier protein in plasma, bovine serum albumin (BSA). The BSA fluorescence signal was quenched due to the APU–BSA complex formation and a weak binding affinity was estimated between APR and BSA. The inclusion of fluorescence, UV–vis absorption, molecular docking, and dynamics simulation techniques employed to broadly investigate the combination of APR with BSA at typical physiological conditions. The thermodynamic results revealed that enthalpy (ΔH⁰) and entropy (ΔS⁰) changes were computed as +11.14 kJ mol⁻¹ and +97.56 J mol⁻¹ K⁻¹, respectively, which represented the binding is principally entropy-driven and the hydrophobic forces acting a significant role in the reaction. Analysis of synchronous and 3-D fluorescence signals revealed microenvironmental variations close to BSA’s Trp and Tyr residues upon APR addition. Both the competitive site marker as well as molecular docking results detected that APR exhibited a stronger binding affinity towards Drug Site 2 (DS2) compared to Drug Site 1 (DS1).</div></div>","PeriodicalId":433,"journal":{"name":"Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}