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Recent advances in the synthesis of [ <i>a</i> ]-benzo-fused BODIPY fluorophores
摘要： This feature article summarizes the di?erent strategies for the synthesis of [a]-benzo-fused BODIPYs that have been reported in the literature until 2018. These p-extended BODIPYs are promising fluorophores for bio-imaging and organic photovoltaic applications due to both their attractive photophysical properties in the near-infrared area and their higher (photo)chemical stability compared to conventional bis-styryl derivatives. The four main strategies described in this review can be used to access either directly the expected [a]-benzo-fused BODIPYs or through the di-/tetra-hydroisoindole.
关键词： organic photovoltaic,fluorophores,near-infrared,BODIPY,bio-imaging
更新于2025-09-04 15:30:14
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Recent Advances and Applications of Near Infrared Spectroscopy for Honey Quality Assessment
摘要： Currently, most of the technologies used to identify honey quality are inefficient and costly. There is a necessity to develop a more effective one for honey quality assessment. Near Infrared Spectroscopy (NIRS) has the potential to be such a technique for its unique characteristics. This study reviews recent advances and applications of NIR spectroscopy in honey authentication domain including constituents, adulteration, brand, botanical origin and geographical origin. It presents a comprehensive using of this technology, with advantages and limitations, in honey quality detection, which offers insights on selecting the most appropriate NIR spectroscopic method for samples presentation, spectral acquisition, spectral pretreatment and modeling. Future research is to be focused on increasing model robustness, developing overall NIR spectroscopic database and a NIR-based integrated technology system on honey quality assessment.
关键词： honey,near infrared spectroscopy,Advances,detection,applications
更新于2025-09-04 15:30:14
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Quantification of Total Phenolic and Carotenoid Content in Blackberries (Rubus Fructicosus L.) Using Near Infrared Spectroscopy (NIRS) and Multivariate Analysis
摘要： A rapid method to quantify the total phenolic content (TPC) and total carotenoid content (TCC) in blackberries using near infrared spectroscopy (NIRS) was carried out aiming to provide reductions in analysis time and cost for the food industry. A total of 106 samples were analysed using the Folin-Ciocalteu method for TPC and a method based on Ultraviolet-Visible Spectrometer for TCC. The average contents found for TPC and TCC were 24.27 mg·g?1 dw and 8.30 μg·g?1 dw, respectively. Modified partial least squares (MPLS) regression was used for obtaining the calibration models of these compounds. The RPD (ratio of the standard deviation of the reference data to the standard error of prediction (SEP)) values from external validation for both TPC and TCC were between 1.5 < RPDp < 2.5 and RER values (ratio of the range in the reference data to SEP) were 5.92 for TPC and 8.63 for TCC. These values showed that both equations were suitable for screening purposes. MPLS loading plots showed a high contribution of sugars, chlorophyll, lipids and cellulose in the modelling of prediction equations.
关键词： bioanalytical applications,chemometrics,blackberries,near infrared,phenolics,carotenoids,Rubus fructicosus
更新于2025-09-04 15:30:14
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Upconversion luminescence modification induced near infrared luminescence enhancement of Bi2Ti2O7:Yb3+, Er3+ inverse opals
摘要： To date, there are comprehensive researches on rare-earth doped photonic band gap (PBG) materials. The PBG materials can effectively modify the up-conversion luminescence (UCL) of rare earth ions. However, few people pay attention to the influence of modification of the UCL of rare earth ions on their near infrared (NIR) luminescence. In this article, the Bi2Ti2O7: Yb3+, Er3+ inverse opal PBG materials were prepared, and the influence of modification of the UCL of Er3+ on their NIR luminescence was investigated systematically by changing the PBG position. The green and red UCL were suppressed when the PBG was overlapped the UCL of Er3+. The UCL modification induced NIR luminescence enhancement was observed in the Bi2Ti2O7: Yb3+, Er3+ inverse opal, which was attributed to the energy redistribution caused by the PBG effect. The suppression of UCL results in that the electrons located at the UCL levels relax to the NIR luminescence level of 4I13/2, causing the NIR luminescence enhancement. Our research can provide a promising method for the enhancement of the NIR luminescence.
关键词： Enhancement,Inverse opal,up-conversion luminescence,Near infrared luminescence
更新于2025-09-04 15:30:14
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Dicyanoisophorone-Based Near-Infrared Emission Fluorescent Probe for Detecting NAD(P)H in Living Cells and <i>in Vivo</i>
摘要： NADH and NADPH are ubiquitous coenzymes in all living cells and play vital roles in numerous redox reactions in cellular energy metabolism. To accurately detect the distribution and dynamic changes of NAD(P)H under physiological condition is essential for understanding its biological functions and pathological roles. In this work, we developed a near-infrared (NIR) emission fluorescent small-molecule probe (DCI-MQ) composed of a dicyanoisophorone chromophore conjugated with a quinolinium moiety for in vivo NAD(P)H detection. DCI-MQ owns the advantages of high water solubility, rapid response, extraordinary selectivity, great sensitivity (detection limit of 12 nM), low cytotoxicity and a NIR emission (660 nm) in response to NAD(P)H. Moreover, the probe DCI-MQ was successfully applied for the detection and imaging of endogenous NAD(P)H in both living cells and tumor-bearing mice, which provides an effective tool for the study of NAD(P)H-related physiological and pathological processes.
关键词： NAD(P)H,near-infrared emission,fluorescent probe,bioimaging,dicyanoisophorone
更新于2025-09-04 15:30:14
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Wide-Range UV-to-Visible Excitation of Near-Infrared Emission and Slow Magnetic Relaxation in Ln <sup>III</sup> (4,4′-Azopyridine-1,1′-dioxide)[Co <sup>III</sup> (CN) <sub/>6</sub> ] <sup>3–</sup> Layered Frameworks
摘要： Trivalent lanthanide ions combined with two linkers, organic 4,4′-azopyridine-1,1′-dioxide (apdo), and inorganic hexacyanidocobaltate(III), gave a series of magnetoluminescent coordination polymers, [{LnIII(apdo)(H2O)4}{CoIII(CN)6}]·2H2O (Ln = Nd, 1; Tb, 2; Dy, 3; Er, 4; Tm, 5; Yb, 6). They are hybrid organic?inorganic layered frameworks composed of cyanido-bridged {Ln2(μ-NC)4Co2} squares linked by Ln?apdo?Ln bridges into a coordination network of a mixed 4- and 8-metal ring topology. Lanthanide(III) complexes, [LnIII(μ-apdo)2(H2O)4(μ-NC)2]+, of a distorted dodecahedral geometry are isolated by diamagnetic [CoIII(CN)6]3? and apdo linkers. As a result, 1?6 reveal field-induced slow relaxation of magnetization, with typical temperature-dependent relaxation of a single-ion origin for NdIII-containing 1, DyIII-containing 3, and YbIII-containing 6. The related alternate-current magnetic data were precisely analyzed, indicating the multiple magnetic relaxation pathways, including a direct process, strong quantum tunneling of magnetization, non-negligible Raman processes, and crucial two-phonon Orbach thermal relaxation. The thermal energy barriers of the Orbach process, ΔE/kB, are 15.1(9) K with τ0 = 9.8(9) × 10?6 s at Hdc = 4500 Oe, 16.1(8) K with τ0 = 9.0(9) × 10?5 s at Hdc = 1500 Oe, and 17.3(6) K with τ0 = 3.2(7) × 10?6 s at Hdc = 700 Oe, for 1, 3, and 6, respectively, proving the single-molecule magnet (SMM) behavior. Because of the presence of [Co(CN)6]3?, 1?6 show strong UV absorption, while the chromophoric apdo leads to the strong absorption in the visible range. As a result, the visible 4f/3d metal-centered emission is quenched, but the near-infrared luminescence from NdIII and YbIII is observed in 1 and 6, respectively. It is realized by Co-to-Ln metal-to-metal, and apdo-to-Ln ligand-to-metal energy transfers; thus, broad UV-to-visible excitation can be explored. Compounds 1?6 form a novel family of functional bimetallic assemblies, incorporating NIR-emissive SMMs as presented for NdCo (1) and YbCo (6) derivatives.
关键词： single-molecule magnets,near-infrared luminescence,coordination polymers,magnetoluminescent,lanthanide
更新于2025-09-04 15:30:14
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Near-Infrared (NIR) Spectrometry as a Fast and Reliable Tool for Fat and Moisture Analyses in Olives
摘要： The evaluation of fat and moisture contents for olive fruits is crucial for both olive growers and olive oil processors. Reference methods, such as Soxhlet extraction, used for fat content determination in olive fruits are time- and solvent- consuming and labor intensive. Near-infrared (NIR) spectroscopy is proposed as a solution toward rapid and nondestructive analyses of olive fruit fat and moisture contents. In the present work, comparative studies of the fat and moisture quantification methods were performed on four cultivars (Arbosana, Arbequina, Chiquitita, and Koroneiki) during six different harvesting time points to determine the potential of NIR as an alternative methodology. The impact of olive paste crushing degree on NIR performance was also investigated using three different grid sizes (4, 6, and 8 mm) on a hammer mill, in addition to a blade crusher. Results indicate a satisfactory correlation between the reference Soxhlet and NIR methods with R2 = 0.995. A comparison study of moisture content was also done on NIR and the use of conventional oven with the R2 value of 0.995. The crushing blade produced higher values in both moisture and fat contents in comparison to the hammer mill. The evaluation indicates that when building a chemometric model, all crush sizes and blade sizes should be represented in the model for highest accuracy.
关键词： Soxhlet extraction,Near-infrared (NIR) spectroscopy,moisture content,olive fruit,fat content,chemometric model
更新于2025-09-04 15:30:14
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Quantitative Determination of Fluorine Content in Blends of Polylactide (PLA)–Talc Using Near Infrared Spectroscopy
摘要： Near-infrared spectroscopy (NIRS) has been widely used for quantitative and/or qualitative determination of a wide range of matrices. The objective of this study was to develop a NIRS method for the quantitative determination of fluorine content in polylactide (PLA)-talc blends. A blending profile was obtained by mixing different amounts of PLA granules and talc powder. The calibration model was built correlating wet chemical data (alkali digestion method) and NIR spectra. Using FT (Fourier Transform)-NIR technique, a Partial Least Squares (PLS) regression model was set-up, in a concentration interval of 0 ppm of pure PLA to 800 ppm of pure talc. Fluorine content prediction (R2 cal = 0.9498; standard error of calibration, SEC = 34.77; standard error of cross-validation, SECV = 46.94) was then externally validated by means of a further 15 independent samples (R2 EX.V = 0.8955; root mean standard error of prediction, RMSEP = 61.08). A positive relationship between an inorganic component as fluorine and NIR signal has been evidenced, and used to obtain quantitative analytical information from the spectra.
关键词： quantitative calibration,fluorine,PLA,polylactide,blends,talc,near infrared spectroscopy
更新于2025-09-04 15:30:14
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Feasibility of indocyanine green fluorescence imaging for intraoperative identification of parathyroid glands during thyroid surgery
摘要： Background: This study assessed the feasibility of near-infrared fluorescence imaging with indocyanine green (ICG) to identify the parathyroid glands (PGs) intraoperatively and to assess their perfusion after thyroid resection. Methods: Patients undergoing elective thyroidectomy were enrolled in this prospective study. An intravenous bolus of 7.5 mg ICG was administered twice: the first bolus to identify the PGs before resection of the thyroid and the second to assess vascularization of the PGs after resection. Results: A total of 30 operations in 26 patients were included. In 17 surgeries (56.7%), fluorescence imaging was of added value, especially to confirm the presence of a suspected PG. No intraoperative or postoperative complications occurred because of the use of ICG. Conclusion: Near-infrared fluorescence imaging with the use of ICG for intraoperative identification of the PGs and the assessment of its vascularization is feasible and safe and can provide more certainty about the location of the PGs.
关键词： near-infrared fluorescence imaging,thyroidectomy,NIRF,indocyanine green,parathyroid gland
更新于2025-09-04 15:30:14
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Indolizine-Cyanine Dyes: Near Infrared Emissive Cyanine Dyes with Increased Stokes Shifts
摘要： Molecular engineering strategies designed to red-shift cyanine dye absorptions and emissions further into the near infrared (NIR) spectral region are explored. Through the use of a novel donor group, indolizine, with varying cyanine bridge lengths, dye absorptions and emissions were shifted deeper into the NIR region than common indoline-cyanines. Stokes shifts resulting from intramolecular steric interactions of up to ~60 nm in many cases were observed and explained computationally. Molecular brightnesses of up to 5,800 deep into the NIR region were observed. Structure-property relationships are explored for the 6 indolizine-cyanine dyes with varying cyanine bridge length and indolizine substituents showing broad absorption and emission tunability. The dyes are characterized by crystallography, and the photophysical properties are probed by varying solvent for absorption and emission studies. Computational data show involvement of the entire indolizine π-system during light absorption, which suggests these systems can be tunable even further into the NIR region through select derivatizations.
关键词： Photophysical Properties,Stokes Shifts,Near Infrared Emissive,Molecular Brightness,Indolizine-Cyanine Dyes
更新于2025-09-04 15:30:14