采用显微成像荧光光谱系统对退变(病变)的软骨及健康软骨样本不同深度位置进行显微探测和荧光光谱采样。结果显示:在非钙化区,退变样本的340/414nm荧光光谱强度低于健康样本,而在钙化区和骨质区,退变样本荧光强度则高于健康样本;2类样...采用显微成像荧光光谱系统对退变(病变)的软骨及健康软骨样本不同深度位置进行显微探测和荧光光谱采样。结果显示:在非钙化区,退变样本的340/414nm荧光光谱强度低于健康样本,而在钙化区和骨质区,退变样本荧光强度则高于健康样本;2类样本在钙化区和骨质区的荧光光谱强度均高于非钙化区。这些现象可能是由于退变发生时,糖基化终产物(advanced glycation end products,AGE)大量积累,破坏了胶原网络的完整性,导致非钙化区荧光强度减弱;而在钙化区及骨质区发生了形态和构成上的改变,导致荧光强度增强。同时,从软骨到骨质的变化过程中,胶原的主要构成从Ⅱ型变成了Ⅰ型,导致骨质区荧光强度增加并发生红移。本文为利用显微成像荧光光谱技术研究关节软骨提供了一定的实验依据和病变特征,有助于相关疾病的早期监测及诊断研究。展开更多
A method for in situ preparation of fluorescent gold nanoclusters(Au NCs) with bovine serum albumin/montmorillonite composite powder(Au NC-BSA/MMT) was developed, and the products were used to detect latent fingermark...A method for in situ preparation of fluorescent gold nanoclusters(Au NCs) with bovine serum albumin/montmorillonite composite powder(Au NC-BSA/MMT) was developed, and the products were used to detect latent fingermarks. In this work, Au NCs were "grown" both inside and on the surface of BSA/MMT clay using one-step reduction of HAu Cl4 by BSA. The as-prepared Au NC-BSA/MMT nanocomposites emit intensive red fluorescence under the excitation of UV-visible light and show stable chemical features and low toxicity. The obtained fluorescent powders were characterized by UV-visible absorption spectroscopy,fluorescence spectroscopy, infrared spectroscopy, transmission electron microscopy/high-resolution transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction to depict their sizes, structural information and optical features. Given their environmentally friendly preparation, simple operation, low cost, efficient UVvisible radiation-dependent photoluminescence and good affinity with finger residues, the in situ synthesized Au NC-BSA/MMT nanocomposite powders were used as an alternative fluorescent developing reagent for developing latent fingermarks deposited on various object surfaces(such as glass, aluminum foil, painted metal, plastic products and weighing papers) for individual identification. As results, the developed fingermarks with clear patterns and satisfactory level-2(minutiae points) and level-3(sweat pores) ridge details were obtained. Notably, treated prints could be excited by red light and emitted near infrared fluorescence, which was beneficial to avoid background interference and reduce the damage caused by UV light. With the advantages of the simple preparation process and good enhancement performance for latent fingermarks, the proposed method might be used in the preparation of various fluorescent probes for detecting trace evidence in forensic sciences.展开更多
文摘采用显微成像荧光光谱系统对退变(病变)的软骨及健康软骨样本不同深度位置进行显微探测和荧光光谱采样。结果显示:在非钙化区,退变样本的340/414nm荧光光谱强度低于健康样本,而在钙化区和骨质区,退变样本荧光强度则高于健康样本;2类样本在钙化区和骨质区的荧光光谱强度均高于非钙化区。这些现象可能是由于退变发生时,糖基化终产物(advanced glycation end products,AGE)大量积累,破坏了胶原网络的完整性,导致非钙化区荧光强度减弱;而在钙化区及骨质区发生了形态和构成上的改变,导致荧光强度增强。同时,从软骨到骨质的变化过程中,胶原的主要构成从Ⅱ型变成了Ⅰ型,导致骨质区荧光强度增加并发生红移。本文为利用显微成像荧光光谱技术研究关节软骨提供了一定的实验依据和病变特征,有助于相关疾病的早期监测及诊断研究。
基金supported by the National Natural Science Foundation of China(51401174)the National Social Science Foundation of China(16AYY015)the Scientific Research Funds of Southwest University of Political Science and Law(2015XZQN-32)
文摘A method for in situ preparation of fluorescent gold nanoclusters(Au NCs) with bovine serum albumin/montmorillonite composite powder(Au NC-BSA/MMT) was developed, and the products were used to detect latent fingermarks. In this work, Au NCs were "grown" both inside and on the surface of BSA/MMT clay using one-step reduction of HAu Cl4 by BSA. The as-prepared Au NC-BSA/MMT nanocomposites emit intensive red fluorescence under the excitation of UV-visible light and show stable chemical features and low toxicity. The obtained fluorescent powders were characterized by UV-visible absorption spectroscopy,fluorescence spectroscopy, infrared spectroscopy, transmission electron microscopy/high-resolution transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction to depict their sizes, structural information and optical features. Given their environmentally friendly preparation, simple operation, low cost, efficient UVvisible radiation-dependent photoluminescence and good affinity with finger residues, the in situ synthesized Au NC-BSA/MMT nanocomposite powders were used as an alternative fluorescent developing reagent for developing latent fingermarks deposited on various object surfaces(such as glass, aluminum foil, painted metal, plastic products and weighing papers) for individual identification. As results, the developed fingermarks with clear patterns and satisfactory level-2(minutiae points) and level-3(sweat pores) ridge details were obtained. Notably, treated prints could be excited by red light and emitted near infrared fluorescence, which was beneficial to avoid background interference and reduce the damage caused by UV light. With the advantages of the simple preparation process and good enhancement performance for latent fingermarks, the proposed method might be used in the preparation of various fluorescent probes for detecting trace evidence in forensic sciences.
