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61.
In this review, the basic principles and apparatus of ECL imaging were briefly introduced at first. Then several latest and representative applications of ECL imaging based on nanomaterials and micro-/nanostructures were overviewed. Finally, the superiorities and challenges in ECL imaging for further development were discussed. 相似文献
62.
To develop a small molecule-based biomarker for in vivo apoptosis imaging, a dansyled amino acid derivative (BNSBA) was designed and synthesized in good yield. The biological evaluation demonstrated that BNSBA selectively binds to apoptotic cancer cells and is localized within the cytoplasm of cells that bound annexin V on the plasma membrane. 相似文献
63.
M. Mirasoli M. Guardigli P. Simoni S. Venturoli S. Ambretti M. Musiani A. Roda 《Analytical and bioanalytical chemistry》2009,394(4):981-987
Classification of cervical intraepithelial neoplasia (CIN) lesions in low-grade (CIN1) or high-grade (CIN2-3) ones is crucial
for optimal patient management, but current histological diagnosis on bioptic samples is often hampered by inter-observer
variability. To allow objective classification, we have exploited the peculiar characteristics of chemiluminescence detection,
such as high sensitivity and easy quantification of the luminescence signal, to perform sequentially in the same tissue section
both an immunohistochemical quantitative detection of p16INK4A (a protein marker of high-grade CIN lesions) and an in situ hybridization for human papillomavirus (generally accepted as
a necessary but insufficient cause of cervical carcinoma). Different label enzymes (alkaline phosphatase and horseradish peroxidase)
were employed in order to avoid any interference between the two assays, and quantitative chemiluminescence image analysis
was used to obtain objective evaluation of sample positivity. The multiplexed method allowed detection of two complementary
biomarkers and provided discrimination between different lesions (non-neoplastic, low-grade and high-grade CIN). This assay
might thus represent an accurate and objective diagnostic test providing important information for counseling, selection of
therapy and follow up after surgical treatment. 相似文献
64.
基于外部光注入的光泵浦自旋垂直腔表面发射激光器(vertical cavity surface-emitting laser,VCSEL)的两个混沌偏振分量,提出了对两个复杂形状目标中的多区域精确测距方案.这里,两个混沌偏振探测波具有飞秒量级快速动态并且被双极性sinc波形调制,使它们具有时空不相关特性.利用这些特性,通过计算多束延时反馈混沌偏振探测波形和与之相对应的参考波形的相关性,实现了对两个复杂形状目标多区域位置矢量精确测量.研究结果表明,对多区域小目标的测距具有非常低的相对误差(低于0.94%).当光电探测器的带宽足够大时,其测距的分辨率达到0.4 mm,并具有很强的抗噪声能力.本文的研究结果在复杂形状目标的精确测距方面具有潜在应用. 相似文献
65.
CdTe quantum dots (QDs), capped with mercaptopropionic acid (MPA), were synthesized and the variation of their fluorescence properties (steady state and lifetime) with pH was assessed in solution and when immobilized in a sol-gel host. Three different sizes of CdTe QDs with excited state lifetimes ranging from 42 to 48 ns and with emission maximum at 540 nm (QD540), 580 nm (QD580) and 625 nm (QD625) were selected. The solution pH affects the maximum emission wavelength (shifts to higher wavelengths of 23, 24 and 27 nm for QD540, QD580 and QD625, respectively), the excited state lifetime and the fluorescence intensity in a reversible way. Linearization of the maximum emission wavelength variation with the pH allows the estimation of an apparent ionization constant (pKa) for each QD: 6.5 ± 0.1 (QD540), 6.1 ± 0.5 (QD580) and 5.4 ± 0.3 (QD625). The variation of the QDs fluorescence properties was further explored using confocal laser scanning microscopy allowing the implementation of a new calibration method for pH imaging in solution. QDs were successfully immobilized on the tip of an optical fiber by dip-coating using sol-gel procedure. The immobilized QDs showed a similar pH behaviour to the one observed in solution and an apparent lifetime of 80, 68 and 99 ns, respectively. The proposed QDs based methodology can be successfully used to monitor pH using wavelength encoded data in imaging and fiber optic sensing applications. 相似文献
66.
New squaraine-based chemosensors SQ1 and SQ2 functionalized with 2-picolyl units were first synthesized and used as highly selective and sensitive colorimetric and fluorometric dual-channel sensors for Cu2+-specific recognition in aqueous systems. Among a series of individual metal ions, only Cu2+ could result in dramatic color changes. We also evaluated their capability of biological applications and found that SQ2 could be successfully employed as a Cu2+-selective probe in the fluorescence imaging of living cells. 相似文献
67.
核酸适配体是利用体外筛选技术,即指数富集的配体系统进化技术(SELEX),从核酸分子文库中得到的寡核苷酸片段。其与靶标物有很高的特异性和亲和力,将适配体作为识别单元的生物传感研究以及适配体偶联成像试剂的生物体内外成像研究在临床诊断中有很大的应用前景,此外,适配体靶向癌细胞或组织的治疗方法相比传统化学治疗副作用更小,在临床上也有极大的应用前景。本文综述了适配体目前在癌症诊断和靶向治疗两个方面的研究进展,并分析现阶段存在的问题以及面临的挑战。 相似文献
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