Near-Infrared Spectroscopy Combined with Absorbance Upper Optimization Partial Least Squares Applied to Rapid Analysis of Polysaccharide for Proprietary Chinese Medicine Oral Solution

Near-infrared (NIR) spectroscopy was applied to reagent-free quantitative analysis of polysaccharide of a brand product of proprietary Chinese medicine (PCM) oral solution samples. A novel method, called absorbance upper optimization partial least squares (AUO-PLS), was proposed and successfully applied to the wavelength selection. Based on varied partitioning of the calibration and prediction sample sets, the parameter optimization was performed to achieve stability. On the basis of the AUO-PLS method, the selected upper bound of appropriate absorbance was 1.53 and the corresponding wavebands combination was 400 - 1880 & 2088 - 2346 nm. With the use of random validation samples excluded from the modeling process, the root-mean-square error and correlation coefficient of prediction for polysaccharide were 27.09 mg·L-1 and 0.888, respectively. The results indicate that the NIR prediction values are close to those of the measured values. NIR spectroscopy combined with AUO-PLS method provided a promising tool for quantification of the polysaccharide for PCM oral solution and this technique is rapid and simple when compared with conventional methods.

AO-MW-PLS method applied to rapid quantification of teicoplanin with near-infrared spectroscopy

Teicoplanin(TCP)is an important lipoglycopeptide antibiotic produced by fermenting Acti-noplanes teichomyceticus.The change in TCP concentration is important to measure in the fermentation process.In this study,a reagent-free and rapid quantification method for TCP in the TCP-Tris-HCl mixture samples was developed using near infrared(NIR)spectroscopy by focusing our attention on the fermentation process for TCP.The absorbance optimization(AO)partial least squares(PLS)was proposed and integrated with the moving window(MW)PLS,which is called AO-MW-PLS method,to select appropriate wavebands.Amodel set that includes various wavebands that were equivalent to the optimal AO-MW-PLS waveband was,proposed based on statistical considerations.The public region of all equivalent wavebands was just one of the equivalent wavebands.The obtained public regions were 1540-1868 nm for TCP and 1114-1310 nm for Tris.The root-mean-square error and correlation coeficient for leave-one-out cross validation were 0.046 mg mL^(-1)and 0.9998 mg mL^(-1)for TCP,and 0.235 mg mL^(-1)and 0.9986 mg mL^(-1)for Tris,respectively.All the models achieved highly accurate prediction effects,and the selected wavebands provided valuable references for designing specialized spectrometers.This study provided a valuable reference for further application of the proposed methods to TCP fermentation broth and to other spectroscopic analysis fields.

A New Heptamethine Cyanine-Based Near-Infrared Fluorescent Probe for Divalent Copper Ions with High Selectivity

A new near-infrared fluorophore 2-(2-Aminoethyl) pyridine-tricarbocyanine (1) was rationally designed and synthe-sized as a fluorescent probe for detection of Cu2+ with high selectivity. The response of Probe 1 is based on the fluorescence quenching upon binding to Cu2+. The sensing performance of the proposed Cu2+-sensitive Probe 1 was then investigated. The probe can be applied to the quantification detection of Cu2+ with a linear concentration range covering from 4.8 × 10-7 to 1.6 × 10-4 mol/L and a detection limit of 9.3 × 10-8 mol/L. The experimental results showed that the response of 1 to Cu2+ was independent of pH in medium condition (pH 6.0-8.0), and exhibited excellent selectivity towards Cu2+ over other common metal cations.

双碳目标下活性染料低温快速皂洗技术研究

文中对活性染料染色织物进行低温快速皂洗,并探究了分步皂洗、一步皂洗工艺对皂洗织物颜色参数和残液吸光度的影响规律,证实了低温快速皂洗技术的可行性。结果表明,采用分步皂洗工艺时,1.0%皂洗剂,在60℃处理10 min时最接近常规皂洗织物颜色参数;采用一步皂洗时,80℃洗涤15min的残液吸光度与100℃洗涤5 min的吸光度值相近,可将皂洗残液色度降低85%以上,该工艺洗得织物的颜色参数和色牢度与常规工艺相当;使用一步皂洗工艺具有操作简单、节能节水、有色废水排放少的特点,利于实现低碳生产。

Near-infrared small molecular fluorescent dyes for photothermal therapy

Near-infrared(NIR)fluorescent dyes based on small organic molecules are characterized with low cytotoxicity,good biocompatibility and minimum interference from auto-fluorescence background,which are widely used in tumor diagnosis.Intensive research on molecular properties and photothermal properties of fluorescent dyes have been explored for non-invasive photothermal treatment of cancer.In this review,we focus on the development of imaging-induced photothermal therapy of small molecules and classification according to the structures of organic molecules including cyanines,phthalocyanines,rhodamine analogues and BODIPYs.

D-A-D structured selenadiazolesbenzothiadiazole-based near-infrared dye for enhanced photoacoustic imaging and photothermal cancer therapy

Near-infrared(NIR)small molecular organic dyes as photothermal agents for cancer photothermal therapy(PTT)have attracted considerable research attention.Herein,two donor-acceptor-donor(D-A-D)structured NIR dyes,BBTT and SeBTT,are rationally designed,where the only difference is one heteroatom within the acceptor unit varying from sulfur to selenium(Se).More importantly,SeBTT NPs exhibit stronger NIR absorbance and higher photothermal conversion efficiency(PTCE≈65.3%).In vivo experiments illustrate that SeBTT NPs can be utilized as a high contrast photoacoustic imaging(PAI)agent,and succeed in tumor suppression without noticeable damage to main organs under NIR photoirradiation.This study presents an effective molecular heteroatom surgery strategy to regulate the photothermal properties of NIR small molecules for enhanced PAI and PTT.

Engineering naphthalimide-cyanine integrated near-infrared dye into ROS-responsive nanohybrids for tumor PDT/PTT/chemotherapy

Photodynamic(PDT)and photothermal therapies(PTT)are emerging treatments for tumour ablation.Organic dyes such as porphyrin,chlorin,phthalocyanine,boron-dipyrromethene and cyanine are the clinically or preclinically used photosensitizer or photothermal agents.Development of structurally diverse near-infrared dyes with long absorption wavelength is of great significance for PDT and PTT.Herein,we report a novel near-infrared dye ML880 with naphthalimide modified cyanine skeleton.The introduction of naphthalimide moiety results in stronger electron delocalization and larger redshift in emission compared with IR820.Furthermore,ML880 is co-loaded with chemotherapeutic drug into ROS-responsive mesoporous organosilica(RMON)to construct nanomedicine NBD&ML@RMON,which exhibits remarkable tumor inhibition effects through PDT/PTT/chemotherapy in vivo.

Tunable near-infrared plasmonic perfect absorber based on phase-change materials

A tunable plasmonic perfect absorber with a tuning range of 650 nm is realized by introducing a 20 nm thick phase-change material Ge2Sb2Te5 layer into the metal–dielectric–metal configuration.The absorption at the plasmonic resonance is kept above 0.96 across the whole tuning range.In this work we study this extraordinary optical response numerically and reveal the geometric conditions which support this phenomenon.This work shows a promising route to achieve tunable plasmonic devices for multi-band optical modulation,communication,and thermal imaging.

Near-infrared dyes, nanomaterials and proteins

Taking the advantage of reduced scattering and low autofluorescence background, the NIR fluorescence probes, such as fluorescence proteins, organic molecules and nanoparticles, not only hold the promise of in vivo imaging of biological processes in physiology and pathology with high signal-to-noise ratio, but also for clinical diagnosis. In this review, we provide an overview of the recent progress on NIR probes,focusing on fundamental mechanisms of NIR dyes and nanoparticles, and protein engineering strategies for NIR proteins.

Visible and near-infrared light activated azo dyes

The photoisomerization properties of azo derivatives have been widely used in the fields of materials and biology.One serious restriction to the development of functional azo-based materials is the necessity to trigger switching by UV light,which damage the corresponding surfaces and penetrate only partially through the matter.Therefore,developing the visible and near-infrared light activated azo switches can solve this problem.This review provides a summary of molecular design strategies for driving the isomerization of azo derivatives with visible light and near-infrared light:(1) smart design directly excited by visible light,(2) the addition of upconversion nanoparticles,(3) the employment of twophoton absorption,(4) indirect excitation in combination with metal sensitizer.

“Crossbreeding”NIR-II flavchromene for PSMA-positive prostate cancer detection and image-guided surgery

Prostate-specific membrane antigen(PSMA)is known to be overexpressed in prostate cancer(PCa).The development of precise and rapid imaging technologies to monitor PSMA is crucial for early diagnosis and therapy.Fluorescence imaging in the second near-infrared window(NIR-II)has emerged as a powerful tool for real-time tracking and in vivo visualization,offering high sensitivity and resolu-tion.However,there is a lack of stable,bright and easy-to-implement NIR-II fluorescent probes for PSMA targeting.Herein,we presented a PSMA-targeting NIR-II fluorescent probe FC-PSMA based onπ-conjugated crossbreeding dyed strategy that affords high stability,large extinction coefficient,and good bright-ness.As demonstrated,FC-PSMA displayed a high fluorescence quantum yield in fetal bovine serum(FBS).Following intravenous injection of FC-PSMA,the tumor-to-normal ratio of fluorescence intensity steadily increased over time,reaching a peak at 48 h(tumor-to-leg ratio=12.16±0.90).This advancement enables precise identification of PC through NIR-II fluorescence imaging,facili-tating high-performance guidance for prostate cancer resection surgery.

Advances in Polymethine Dyes for Near-Infrared Organic Photodiodes

Near-infrared organic photodiodes (NIR OPDs) have tremendous potential in industrial, military, and scientific applications, due to their unique features of lightweight, low toxicity, high structural flexibility, cooling-system-free, etc. However, the overall performance of currently available NIR OPDs still lags behind the commercial inorganic photodetectors, ascribed to the critical challenge of realizing organic semiconductors with sufficiently low optical bandgap and excellent optoelectronic properties simultaneously. Among various types of NIR-absorbing organic semiconductors, polymethine dyes not only possess advantages of simple synthesis and structural diversity, but also show fascinating optical and aggregation features in the solid state, making them attractive material candidates for NIR OPDs. In this review, after a brief introduction of NIR OPDs and polymethine dyes, we comprehensively summarize the advances of polymethine dyes for broadband and narrowband NIR OPDs, and further introduce their applications in all-organic optical upconversion devices and photoplethysmography sensors. In particular, the relationship between the chemical structure and the aggregation behaviors of polymethine dyes and the device performance is carefully discussed, providing some important molecular insights for developing high performance NIR OPDs.

New Soluble Near-Infrared Dyes Based on Terrylene Diimides with Four Aromatic Heterocycles

Terrylene diimides with four aromatic heterocycles(AHTDIs)were synthesized under Stille Cross-coupling conditions and fully characterized by NMR and mass spectrometry.The aggregation of the terrylene diimide(TDI)was suppressed by four heterocycles substituents on the bay region,and these AHTDIs exhibited good solubility in common organic solvents.The effects of the substituted groups on the optical and electrochemical properties were also investigated.The introduction of four aromatic heterocycles on the bay of TDI resulted in significant red-shifts of the absorption peak(100 nm),corresponding to a decrease in the band gap from 1.82 to 1.50 eV.Furthermore,with four rich electron aromatic heterocycles,the AHTDIs showed 280 mV negative-shifts of first oxidation poten-tials and a new oxidation wave,corresponding to an increase in the HOMO levels from−5.60 to−5.28 eV.

Benzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole-porphyrin-based near-infrared dyes

Benzo[1,2-c;4,5-cʹ]bis[1,2,5]thiadiazole(BBT)has intrinsic diradical character and herein it is used to construct organic near-infrared(NIR)dyes together with the aromatic porphyrin unit.Three BBT-porphyrin hybrid dyes 1-3 with different linkage modes are synthesized by Pd-catalyzed Sonogashira crosscoupling between meso-ethynylene porphyrin units and monobromo-/dibromo-BBT,or through unexpected homocoupling between the BBT units.They all possess small open-shell diradical character and display intense NIR absorption in the range of 800-1000 nm.They also exhibit amphoteric redox behavior.BBT-based diradicaloids are thus good candidates for organic NIR dyes.

不同浓度范围废水COD检测条件探讨

针对一些废水在处理过程中COD范围差异大，COD测定准确度、精密度低的问题。考察了不同浓度范围影响COD测定的关键性因素，结果显示：在440、600nm处，Cr（Ⅵ）浓度不适会引起COD测定准确度、精密度降低。采用c（1／6KzCr20，）为0．02、0．05、0．5mol／L的重铬酸钾溶液，分别对COD为0-50、50～150、150—1500ms／L的溶液作标线，标线的线性回归系数R^2均〉0．999，平行水样相对偏差为1．19％～2．61％，加标回收率为95．3％-104．4％。

紫外线吸收剂对涤纶的上染及其紫外线吸收性能

为研究紫外线吸收剂对涤纶织物吸收紫外线性能的影响,将5只苯并三唑类紫外线吸收剂经分散后用高温高压浸染法使其上染到涤纶织物上,以残液法测试紫外线吸收剂对涤纶的上染率,用紫外线透过率表征织物的紫外线吸收性能。结果表明：选用的紫外线吸收剂可以在130℃下保温40～60 min上染涤纶织物,紫外线吸收剂结构、分子质量、上染温度和用量都会影响其对涤纶的上染率,分子质量适中、芳环较多、疏水性基团比例较高的紫外线吸收剂对涤纶的上染率较高;上染率较高的紫外线吸收剂能更明显地改善涤纶织物的紫外线吸收性能,上染率不高但分子中含有2个分子内氢键螯合环的紫外线吸收剂也能明显提高涤纶织物的紫外线吸收能力。

天然色素染料敏化太阳能电池的制备

通过萃取西藏林芝核桃果皮、江孜沙棘果实以及拉萨紫草根部的天然色素,分析研究了西藏天然色素光吸收性能;利用以上3种天然色素以及它们的混合色素,研制了染料敏化太阳能电池。结果表明,核桃与紫草的混合色素(TiO2薄膜多层)DSSC电池效率最高,达到8.2%。

多种因素对MIL-101(Cr)选择性吸附水溶液中染料的影响

在多种条件下研究了金属有机框架MIL-101(Cr)对阳离子型染料(亚甲基蓝、罗丹明B)和阴离子型染料(甲基橙、酸性铬蓝K)的吸附性质,主要研究了MIL-101(Cr)对亚甲基蓝和甲基橙的选择性吸附作用。结果表明,中性环境下无论在单组分还是双组分体系中MIL-101(Cr)对阴离子型染料的吸附能力均大于对阳离子型的吸附能力。在p H=3,T=300 K的条件下,选择性系数β可达5.9,但随着p H的增加,选择性系数逐渐降低。相比之下,温度对吸附的选择性影响不大。选择性吸附的机理可以解释为:由于表面带正电荷,MIL-101(Cr)对阴离子型染料产生静电吸引作用;相反,对阳离子型染料的排斥作用而降低了其吸附能力。另外,乙二胺改性提高了MIL-101(Cr)对阴离子型染料的选择吸附性能,而草酸改性降低了选择吸附性。

蒙脱石粘土改性吸附剂处理印染废水实验研究

通过实验得到天然蒙脱石粘土改性和提高蒙脱石粘土吸附剂处理印染废水效果的方法，阐述了蒙脱石粘土改性和吸附有机污染物的机理。研究结果表明，天然蒙脱石经钠化和无机聚合物改性处理后，大幅度地提高了天然蒙脱石粘土对有机污染物的吸附能力。改性粘土吸附剂在投加量为０．１％时，处理红色印染废水，ＣＯＤ去除率８５％，脱色率８８％以上；处理兰色废水，ＣＯＤ去除率９４％，脱色率达９８％。处理后的水质达到回用要求。模拟实验表明，该吸附剂对含有各种类型染料的印染废水都有稳定的处理效果。本研究为印染废水处理提供了廉价高效的吸附剂。

近红外吸收功能菁染料的研究进展

主要综述了在近红外吸收功能菁染料的合成过程中所使用的缩合剂及其特点、典型合成反应,并且综合分析了菁染料最大吸收波长、稳定性与其结构的关系,简述了近红外吸收功能菁染料的应用途径,从中归纳出了近红外吸收功能菁染料的发展方向。