Development of Novel Nanocarrier-Based Near-Infrared Optical Probes for In Vivo Tumor Imaging

Optical imaging with near-infrared (NIR) fluorescent probes is a useful diagnostic technology for in vivo tumor detection. Our plan was to develop novel NIR fluorophore-micelle complex probes. IC7-1 and IC7-2 were synthesized as novel lipophilic NIR fluorophores, which were encapsulated in an amphiphilic polydepsipeptide micelle “lactosome”. The fluorophore-micelle complexes IC7-1 lactosome and IC7-2 lactosome were evaluated as NIR fluorescent probes for in vivo tumor imaging. IC7-1 and IC7-2 were synthesized and then encapsulated in lactosomes. The optical properties of IC7-1, IC7-2, IC7-1 lactosome and IC7-2 lactosome were measured. IC7-1 lactosome and IC7-2 lactosome were administered to tumor-bearing mice, and fluorescence images were acquired for 48 h. IC7-1 and IC7-2 were successfully synthesized in 12% and 6.3% overall yield, and maximum emission wavelengths in chloroform were observed at 858 nm and 897 nm, respectively. Aqueous buffered solutions of IC7-1 lactosome and IC7-2 lactosome showed similar fluorescence spectra in chloroform and higher or comparable quantum yields and higher photostability compared with ICG. Both lactosome probes specifically visualized tumor tissue 6 h post-administration. IC7-1 lactosome and IC7-2 lactosome could be promising NIR probes for in vivo tumor imaging.     

Comparison of In Vivo Optical Systems for Bioluminescence and Fluorescence Imaging

In vivo optical imaging has become a popular tool in animal laboratories. Currently, many in vivo optical imaging systems are available on the market, which often makes it difficult for research groups to decide which system fits their needs best. In this work we compared different commercially available systems, which can measure both bioluminescent and fluorescent light. The systems were tested for their bioluminescent and fluorescent sensitivity both in vitro and in vivo. The IVIS Lumina II was found to be most sensitive for bioluminescence imaging, with the Photon Imager a close second. Contrary, the Kodak system was, in vitro, the most sensitive system for fluorescence imaging. In vivo, the fluorescence sensitivity of the systems was similar. Finally, we examined the added value of spectral unmixing algorithms for in vivo optical imaging and demonstrated that spectral unmixing resulted in at least a doubling of the in vivo sensitivity. Additionally, spectral unmixing also enabled separate imaging of dyes with overlapping spectra which were, without spectral unmixing, not distinguishable.     

Polymer-and Glass-based Fluorescence Standards for the Near Infrared (NIR) Spectral Region

The widespread use and acceptance of fluorescence techniques especially in regulated areas like medical diagnostics is closely linked to standardization concepts that guarantee and improve the comparability and reliability of fluorescence measurements. At the core of such concepts are dependable fluorescence standards that are preferably certified. The ever rising interest in fluorescence measurements in the near-infrared (NIR) spectral region renders the availability of spectral and intensity standards for this wavelength region increasingly important. This encouraged us to develop approaches to solid NIR standards based upon dye-doped polymers and assess their application-relevant properties in comparison to metal ion-doped glasses. The overall goal is here to provide inexpensive, easily fabricated, and robust internal and external calibration tools for a broad variety of fluorescence instruments ranging e.g. from spectrofluorometers over fluorescence microscopes to miniaturized fluorescence sensors.     

Near-Infrared Imaging Using a High-Speed Monitoring Near Infrared Hyperspectral Camera(Compovision)

This review paper reports near-infrared (NIR) imaging studies using a newly-developed NIR camera, Compovision. Compovision can measure a significantly wide area of 150 mm×250 mm at high speed of between 2 and 5 s. It enables a wide spectral region measurement in the 1 000～2 350 nm range at 6 nm intervals. We investigated the potential of Compovision in the applications to industrial problems such as the evaluation of pharmaceutical tablets and polymers. Our studies have demonstrated that NIR imaging based on Compovision can solve several issues such as long acquisition times and relatively low sensitivity of detection. NIR imaging with Compovision is strongly expected to be applied not only to pharmaceutical tablet monitoring and polymer characterization but also to various applications such as those to food products, biomedical substances and organic and inorganic materials.     

LIFA System for Fluorescence Lifetime Imaging Microscopy (FLIM)

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LIFA System for Fluorescence Lifetime Imaging Microscopy (FLIM)     

近红外光谱法测定缓释制剂中冰片释放量

利用近红外光谱技术与化学计量学方法建立了冰片缓释样品近红外光谱与冰片浓度之间的定量模型,以实现冰片释放量的快速测定。配制与缓释制剂具有相同物质体系的的冰片醇水溶液,获取其近红外光谱,采用偏最小二乘法(PLS)建立冰片含量预测模型并考察了图谱类型、建模样品浓度及建模区间对校正模型和预测结果的影响。结果表明采用原始近红外光谱,在5 314～7 032 cm-1区间,将样品按照中高浓度、低浓度范围建模可以获得最佳校正结果与预测结果。最后采用所建的中高浓度区模型测定了冰片包合物在醇水体系中冰片含量,实现了对缓释制剂冰片累加释放量的快速测定,可为冰片缓释制剂的研发快速提供评价数据。     

Fluorescence Anisotropy Studies on Bodipy (Pyrromethene 546) Dye as a Novel Thermal Probe

Journal of Fluorescence - In the present work, fluorescence anisotropy studies of BODIPY (pyrromethene 546 or C14H17BF2N2) dye have been performed and found that it has a potential to be used as a...     

Novel Zinc(II) Bis(Dipyrromethenate)-Doped Ethyl Cellulose Sensors for Acetone Vapor Fluorescence Detection

In this paper, we report on the results of spectrofluorimetric study of new fluorescent sensor based on [Zn₂L₂] doped in ethyl cellulose. The sensor optical signal is based on the rapid fluorescence quenching in the presence of acetone vapor. The acetone vapor detection limit in a gas mixture by means of sensor based on [Zn₂L₂] doped in ethyl cellulose is 1.68 ppb. Being highly sensitive to the acetone acetone presence, instant in response and easy to use, the sensor can find an application for the noninvasive diagnostics of diabetes as well as for the monitoring of the content of acetone acetone in the air at industrial and laboratory facilities.

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Graphical Abstract

     

Novel Comparative Synchronous Spectrofluorimetric Study of Benzo(a)pyrene Using Beta-Cyclodextrin and Calix(8)arene as Fluorescence Enhancers

Successfully benzo(a)pyrene could be quantitified in environmental samples by a novel synchronous spectrofluorimetric techniques at a constant wavelength difference Δλ?=?120 nm, using beta-cyclodextrin ‘β-CD’ and calix(8)arene as fluorescence enhancers, where a linear calibration curve was obtained in a concentration range of 900–14,400 pg mL^?1 and 18–360 pg mL^?1 and the detection limit of 380.00 pg mL^?1 and 12.08 pg mL^?1 (which is well below the maximum contaminant concentration for benzo(a)pyrene set by the Environmental Protection Agency ‘EPA’) using both enhancers, respectively. The method can be easily adopted for determination of benzo(a)pyrene in aqueous media including tap water, river water and complex water samples. The recoveries obtained were 85.13–113.36 % with RSD?<?4 %. The proposed method was validated according to International Conference of Harmonization (ICH) guide lines and successfully applied to determine benzo(a)pyrene in pure form and in water samples including contaminated environmental water samples. All the results obtained were compared with those of a published method, where no significant difference was observed.     

一种测量变折射率透镜阵列（SLA）的传递函数的新方法

本文提出了一种与计算机技术相结合、利用ＣＣＤ像感器件测定变折射率透镜阵列传递函数的方法，该方法比较接近于变折射率透镜阵列有实际使用环境，精确度高，测量速度快，而且简便易行，测量结果也较为全面。该方法已用于光电图文扫描仪中变折射率透镜阵列的设计及测量，并获得了满意的结果。     

FTIR结合主成分分析法对直肠癌转移淋巴结的研究

应用傅里叶变换红外光谱(FTIR)联合主成分分析法(PCA),分析直肠癌转移淋巴结的谱学特征,并对直肠癌转移淋巴结和非转移淋巴结进行线性判别分析。80例直肠癌转移淋巴结和80例未转移淋巴结进行FTIR光谱分析,计算峰强并进行主成分分析,得出在波数4 000～1 700 cm-1范围主成分1(Principal components 1,PC1)是3 260 cm-1,PC2为1 740 cm-1。波数1 700～1 000 cm-1范围,PC1为1 640 cm-1,PC2为1 080 cm-1,将良、恶性淋巴结光谱3 260,1 740,1 640,1 080 cm-1相对峰强比(I/I_{1 460})和波数1 080和1 300 cm-1进行t检验,良、恶性结果差异有统计学意义(p<0.05),表明癌转移淋巴结中蛋白含量、蛋白的形成、氨基酸增多;脂肪含量明显减少与癌组织中无氧酵解脂肪含量减少有关。将相对峰强比(I_{1 080}/I_{1 460}, I_{1 640}/I_{1 460}, I_{3 260}/I_{1 460}, I_{1 740}/I_{1 460}, n=160)进行PCA聚类分析,结果显示可以将良恶性淋巴结鉴别,良性淋巴结聚类在第一和四象限,恶性淋巴结聚类在二和三象限。将相对峰强比、1 080和1 300 cm-1进行线性判别分析(LDA),将25例淋巴结作为验证集进行分析,得出PCA/LDA模型的敏感度是87.5%,特异度是88.5%。结果表明傅里叶变换红外光谱分析技术可成为术中原位、在体和快速诊断直肠癌淋巴结转移的一种简便方法。     

激光本振红外光谱干涉成像及其艇载天文应用展望(特邀)

本文分析了红外干涉成像现状和难点,介绍了激光本振红外相干探测的原理,阐述了基于电子学的红外光谱细分和干涉成像原理,讨论了激光本振红外阵列探测器形式.激光本振和相干探测器的设置,可保证两个望远镜的红外信号相位的正确传递,在电子学实施窄带滤波形成的窄带红外信号有利于实现长基线干涉成像.在此基础上,类似微波综合孔径射电望远镜...     

虉草粗蛋白近红外定量分析模型的建立

虉草（Phalaris arundinacea L.）为多年生冷季型禾本科高产牧草,粗蛋白（CP）是评价饲草品质的关键指标,但目前的化学分析方法存在诸多缺点,寻求高效、快速、准确、安全的虉草CP测定方法是现代草地畜牧业发展和草原生态恢复急需解决的实际问题。本研究旨在利用近红外光谱（NIRS）建立虉草CP的定量分析模型,为快速测定虉草CP提供有效方法。试验采集不同品种（品系）、生育期、栽培条件、干燥方式、生长年限、部位以及刈割次数的虉草样品454份,采用瑞士Buchi公司的傅里叶近红外光谱仪和Operator软件采集原始光谱,应用K-S算法剔除具有相似光谱的样品,筛选出210份用于建模和模型评价。通过凯氏定氮法测定210份样品的粗蛋白含量并在Management console软件中对光谱进行赋值,再采用软件NIRcal 5.4按照6∶3的比例将样品随机分为校正集和验证集,并剔除异常样品,运用不同的光谱预处理、回归算法、建模波段和主成分数建立8个虉草CP含量的近红外定量分析模型,通过外部验证表明8个模型均可以进行实际测定。最后比较不同的统计学参数获取最佳模型。结果表明,采用4 000~10 000 cm-1的建模光谱波段、sa3+ncl+db1（3点平滑+趋近归一化+一阶导数处理）的预处理方法、8/1-4的初/次级主成分数和偏最小二乘法（PLS）所建的模型为最佳模型,其校正决定系数（R2_cal）为0.982 1,验证决定系数（R2_val）为0.980 2,均大于0.98,表明预测性能优秀;校正标准差（SEC）和验证标准差（SEP）分别为0.780 2和0.783 2,均较小且非常接近,表明模型的分析精度很高并具有很好的适应性;残差（BIAS）为-0.000 5,接近于0,说明模型的稳定性很高,对外界因素不敏感;预测相关系数（r）为0.99,可见样品化学值与定标模型预测值的相关度极高;相对分析误差（RPD）为7.37,RPD>4.0表明模型能够很好地进行定量分析。综上,该试验在国内首次建立了虉草CP近红外定量分析模型,该模型样品来源多、数量大、分布范围广,预测精度和准确度高,适用范围大,为快速测定虉草粗蛋白提供了有效方法,在虉草品质分析、育种、家畜日粮配置以及草产品评价流通等方面具有应用前景。     

近红外光谱快速分析技术及其在动物饲料和产品品质检测中的应用

近红外光谱是近年来发展最快、最引人注目的光谱学技术。主要介绍了近红外光谱技术的基本原理和发展, 包括近红外光谱预处理技术如微分处理、信号平滑等技术的发展和近红外光谱分析模型如多元线性回归、主成分分析、偏最小二乘法和人工神经网络等的发展。综述了国内外近几年来此技术在动物饲料和产品品质检测中的应用。文献调查显示, 近红外光谱分析技术以其快速、无损、不污染环境等诸多优点在国内外饲料和动物产品检测方面得到广泛应用。在饲料分析方面,近红外不仅能用于其常量成分干物质、粗蛋白、粗纤维、粗脂肪等的测定,而且能用于微量成分、有毒有害成分的测定。在动物产品分析方面,该技术已用于禽蛋、牛肉、羊肉、猪肉等的各种物理和化学指标的测定。文中详细给出了已经报道的利用近红外光谱技术测定饲料和动物产品测定指标和光谱处理以及模型建立的情况, 并讨论了近红外光谱快速检测技术的在饲料分析和动物产品分析领域的应用新趋势和局限性。     

A Novel Highly Sensitive and Selective Fluorescent Sensor for Imaging Copper (II) in Living Cells

In this work, we designed and synthesized a novel quinolin-based derivative which exhibited signaling behaviors for Cu²⁺. Upon the addition of Cu²⁺ to the solution of the molecule, it displayed an obvious fluorescence quenching in a linear fashion due to the formation of a 1:1 metal–ligand complex. This fluorescent sensor exhibited a rare sensitivity toward Cu(II) (the level of magnitude could be 6?×?10^?8), a rapid response (<10 s) and also high selectivity toward Cu²⁺ over other metal ions such as Na⁺, K⁺, Ca²⁺, Mg²⁺, Ba²⁺, Fe³⁺, Mn²⁺, Hg²⁺, Pb²⁺, Cd²⁺, Cr³⁺, Co²⁺, Zn²⁺ and Al³⁺. Simultaneously, the cell imaging experiments and filter paper test demonstrated its extensive applicability.     

Fluorescent Function-Spacer-Lipid Construct Labelling Allows for Real-Time in Vivo Imaging of Cell Migration and Behaviour in Zebrafish (Danio Rerio)

Real-time in vivo imaging of cell migration and behavior has advanced our understanding of physiological processes in situ, especially in the field of immunology. We carried out the transplantation of a mixed population of blood cells from adult zebrafish (Danio rerio) to 2?day old embryos. The blood cells were treated ex vivo with Function-Spacer-Lipid constructs (FSL) incorporating either fluorescein or Atto488 fluorophores (FSL-FLRO4-I or -II). Excellent labeling efficiency was demonstrated by epifluorescence microscopy and FACScan analysis. Real-time video imaging of the recipient fish showed that the functionality of these cells was retained and not affected by the labeling. The usefulness of FSL-FLRO4-I as a contrast agent in microangiography was explored. Overall, we found both FSL-FLRO4-I and-II promising labeling dyes for real-time in vivo imaging in zebrafish.     

一种新型的白光LED用绿色荧光粉Ca_8MgLu(PO_4)_7∶Tb~(3+)

采用高温固相法合成一种单一纯相绿色荧光粉Ca8Mg Lu(PO4)7∶Tb3+,通过X射线衍射(XRD)、荧光光谱(PLE,PL)和荧光寿命曲线研究了Ca8Mg Lu(PO4)7∶Tb3+的发光性能。Ca8Mg Lu(PO4)7∶Tb3+能被378nm的近紫外光激发,Tb3+发生5D4-7F5跃迁发出绿光,色坐标为(0.324,0.592)。Ca8Mg Lu(PO4)7∶Tb3+的量子效率可达84%,热猝灭性能良好:在150℃和200℃的发光强度积分分别是25℃的90.71%和86.36%。研究结果表明Ca8Mg Lu(PO4)7∶Tb3+是一种理想的适于NUV-LED芯片激发的白光LED用绿色荧光粉。     

Holographic Interferometry (HI), Infrared Vision and X-Ray Fluorescence (XRF) spectroscopy for the assessment of painted wooden statues: a new integrated approach

Wood has been routinely employed in decorative arts, as well as in sculptures and paintings (support) during the Middle Ages, because of its unique aesthetic virtues. It may safely be assumed that wood, as a material for monumental sculpture, was much more commonly employed in the mediaeval period than existing examples would seem to indicate (Bulletin of the metropolitan Museum of Art, 2013). Wood is easily obtainable; it could be carved and put in place with less difficulty than stone, it is chemically stable when dry, and its surface offers a compatible substrate for paint application. However, the use of wood is not without pitfalls, and requires an understanding of its anisotropic and hygroscopic nature. It is also dimensionally unstable and subject to deterioration by fungi and insects. Moisture-related dimensional changes are certainly among the most challenging problems in painting conservation. With the purpose of preventing important damages, the use of non-or microdestructive testing (NDT) techniques is undoubtedly of paramount interest for painted wooden statues of great value. This work has a threefold purpose: (1) to validate the effectiveness of an integrated approach using near-infrared (NIR) reflectography, square pulse thermography (SPT), and holographic interferometry (HI) techniques for discovering old repairs and/or inclusions of foreign materials in a wooden structure, (2) to confirm and approximately date the restoration carried out by x-ray fluorescence (XRF) spectroscopy and energy-dispersive x-ray spectroscopy (EDS) (that is assembled with a scanning electron microscopy—SEM) techniques, and (3) to combine into a multidisciplinary approach two quantitative NDT results coming from optical and thermographic methods. The subject of the present study was a statue named “Virgin with her Child” (XIV century), whose origins are mysterious and not properly documented.