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1.
通过聚二烯丙基二甲基胺盐酸盐和氯金酸制备阳离子纳米金,将纳米金和5-氨基乙酰丙酸(5-aminolevulinic acid, 5-ALA)通过静电吸附作用有效结合得到新型光敏剂。应用共振瑞利散射光谱, 紫外-可见吸收光谱, 透射电镜和激光散射等方法对其进行了表征。结果表明通过这种方法纳米金与5-ALA可以有效结合。这种新型光敏剂对提高光动力学疗法临床疗效具有重要指导意义。  相似文献   

2.
应用荧光光谱技术监测了鲜红斑痣(PWS)光动力治疗(PDT)中的光敏剂血药浓度与光产物生成。以532 nm倍频Nd∶YAG激光器作为PDT照射光源与荧光激发光源,以光谱仪与ICCD采集荧光光谱。在系统验证实验中,构建含有血卟啉单甲醚(HMME)的小鼠正常皮肤的荧光基本光谱,通过最小二乘光谱拟合区分HMME荧光(624 nm)与光产物荧光(652 nm)。含有PSD-007的病人患区荧光光谱拟合采用相同基本光谱,获得不同病人个体具有显著差异的光敏剂血药浓度曲线与光产物生成漂白曲线。所建立的荧光光谱监测系统与光谱拟合方法可为PDT精确量化剂量学方法的建立提供技术手段,所得结果有利于制定个性化的PDT治疗方案。  相似文献   

3.
TH742.642006054715激光共聚焦显微镜观察光敏剂ALA和HMME在肿瘤细胞的胞内分布=CLSMi maging of5-ALA and HMMEintumor cells[刊,中]/肖卫东(第三军医大学新桥医院.重庆(400038)),陈炜…//激光杂志.—2006,27(2).—95使用激光共聚焦显微镜观察光敏剂5-ALA和HMME在结肠癌SW480细胞及红白血病K562细胞的胞内分布。5-ALA及HMME进入肿癌细胞早期主要分布于胞膜,而在后期主要以颗粒状荧光分布于胞质,5-ALA分布相对弥散,HMME分布相对集中,核内分布极少。光敏剂5-ALA和HMME主要分布于肿瘤细胞的胞质,表明它们的光化学作用位…  相似文献   

4.
应用荧光光谱技术研究溶液中血卟啉单甲醚(HMME)的光漂白与光产物生成。以532 nm倍频Nd∶YAG激光器照射样品,功率密度为100 mW·cm-2,以光学多通道分析仪(OMA)采集荧光光谱。照光过程与荧光光谱采集同步进行。通过构建基本光谱与最小二乘拟合,由单条实测光谱中分解求得HMME荧光(613 nm)、光产物荧光(639 nm)及自体荧光的强度。HMME初始浓度不超过10 μg·mL-1时符合荧光-浓度线性函数关系。对照光过程的荧光光谱监测同时观察到HMME漂白、光产物生成与漂白,以及样品光学特性变化引起的自体荧光强度起伏。光产物漂白后的二次产物引起样品光学特性显著改变。所建立的荧光光谱探测系统与光谱分析方法可满足光敏剂漂白特性体外研究的需要,并为光动力治疗的剂量学在体监测提供有效研究方法。  相似文献   

5.
激光医学     
探讨新型光敏剂血叶琳单甲醚(HMME)激光诱发药物荧光与激光诱发自体荧光在肺癌组织中的光谱区别。15例肺癌病人(药物组)术前3h静脉注射HMME 3 rng/kg,20例肺癌病人(对照组)术前不注射HMME,使用三倍频 Nd:YAG激光(波长355 nm)和多光道分析仪(OMA)对切除肺癌标本的癌组织进行激光诱  相似文献   

6.
血啉甲醚的时间分辨荧光光谱研究   总被引:3,自引:1,他引:2  
实验研究了用于肿瘤光动力学诊断的第二代新型光敏剂血啉甲醚(HMME)分别在不同血型人血清和生理盐水环境中的时间分辨光谱,同时还研究了在不同荧光发射峰处的荧光寿命以及光敏剂浓度对荧光寿命的影响。结果表明:HMME在625和690nm处的荧光寿命基本相同,无显著差异。HMME在生理盐水和人血清环境中的荧光寿命具有显著差异,分别为14.6和16.6ns,同时实验结果还表明光敏剂浓度对荧光寿命没有影响。结论对于开展肿瘤的时间分辨药物荧光光谱诊断与成像技术具有重要的指导意义。  相似文献   

7.
Q632006010796两亲性光敏剂血卟啉单甲醚在不同溶液体系中的存在状态=Existence state of HMMEin different solvents as anamphiphilic photosensitizer[刊,中]/王颖(解放军总医院激光医学科.北京(100853)),刘凡光…∥中国激光医学杂志.—2005,14(3).—137-145根据单体和聚集态光敏剂吸收光谱特征不同的原理,通过测定脂水两亲性HMME、疏水性HpD在不同浓度不同溶液中的吸收光谱和荧光激发光谱,定性分析了不同条件下HMME的存在状态,并利用公式定量分析了HMME的缔合数、聚集平衡常数及各浓度下的缔合度,为了解HMME-PDT过程中HMME…  相似文献   

8.
采用溶剂热法制备了Mn离子掺杂的ZnS纳米粒子(ZnS∶Mn),然后利用正硅酸乙酯(TEOS)的水解反应对其进行了不同厚度的SiO2无机壳层包覆。采用X射线衍射(XRD)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)及荧光发射光谱(PL)对样品的结构及光学性质进行了表征和研究。包覆SiO2壳层后,粒子的粒径明显增大并且在ZnS∶Mn纳米粒子表面可以观察到明显的SiO2壳层。XPS测试印证了ZnS∶Mn/SiO2的核壳结构。随着SiO2壳层的增厚,ZnS∶Mn/SiO2的Mn离子的发光先增强后减弱,这是因为SiO2壳层同时具有表面修饰和降低发光中心浓度这两种相反的作用。当壳层厚度(壳与核的物质的量的比)达到5时,发光效果达到最好,其强度达到未包覆样品的7.5倍。  相似文献   

9.
采用溶剂热法成功制备了Nd^3+敏化的掺杂Ca^2+的NaYF^4∶Yb/Tm/Ca@NaGdF4∶Nd/Yb核-壳上转换纳米粒子。针对Tm^3+多光子过程中产生的蓝色及紫外上转换发光,研究了敏化剂Nd^3+、Yb^3+的含量以及激发功率等关键因素对荧光性能的影响,并用介孔二氧化硅(mSiO2)对其表面进行修饰,得到具有良好亲水性的上转换纳米粒子,通过TEM、XRD、FT-IR和荧光光谱对其形貌、结构和荧光性能进行表征。结果表明,制备的纳米粒子为纯六角相,表面均匀地包覆了一层mSiO2,在808 nm近红外光激发下,壳层中Nd 3+和Yb 3+的摩尔分数分别为50%和10%时表现出强烈的上转换蓝光(1D2→3F4,1G4→3H6)和紫外光(1I6→3F4,1D2→3H 6),在光动力疗法和荧光成像方面具有潜在的应用价值。  相似文献   

10.
采用模板合成以及溶胶凝胶方法制备了金纳米棒核/二氧化硅壳(GNR@SiO2)纳米复合粒子,探讨了这种新型纳米复合结构的可控制备、光谱性质、细胞毒性和细胞成像。通过紫外可见分光光度计、透射电镜、共聚焦显微镜对样品进行表征,结果表明:通过对反应时间的调控,获得的纳米复合粒子的二氧化硅壳层厚度可以控制在20~30nm。由于二氧化硅壳层的存在,大大提高了金纳米棒的稳定性,同时降低了金纳米棒的细胞毒性;此外,由于二氧化硅壳层具有良好的化学修饰作用,因此可以将荧光探针分子标记在二氧化硅壳层表面,修饰后的纳米复合粒子可以通过细胞内吞作用进入细胞,从而实现细胞内的光学成像。因此,该纳米粒子复合材料在生物传感、细胞成像以及光热治疗等方面有着良好的应用前景。  相似文献   

11.
We investigated the effect of photodynamic therapy (PDT) with hematoporphyrin monomethyl ether (HMME) on the viability of Streptococcus mutans (S. mutans) cells on biofilms in vitro. Streptococcus mutans is the primary etiological agent of human dental caries. Since dental caries are localized infections, such plaque-related diseases would be well suited to PDT. The diode laser used in this study had the wavelength of 635 nm, whose output power was 10 mW and the energy density was 12.74 J/cm2. HMME was used as photosensitizer. Samples were prepared and divided into five groups: (1) HMME; (2) Laser; (3) HMME Laser; (4) Control group ( ) with chlorhexidine; and (5) Control group (-) with sterile physiological saline. Inoculum of S. mutans incubated with HMME also examined with fluorescence microscopy. PDT exhibited a significantly (P < 0.05) increased antimicrobial potential compared with 20 μm/mL HMME only, laser only, 0.05% chlorhexidine, and 0.9% sterile physiological saline, which reduced the S. mutans of the biofilm most effectively. Laser and 0.05% chlorhexidine were caused reduction in the viable counts of S. mutans significantly different (P < 0.05) also, but these two test treatments did not statistically differ from each other. HMME group did not statistically differ with negative control group. Fluorescence microscopy indicated that HMME localized primarily in the S. mutans of the biofilm. It was demonstrated that HMME-mediated PDT was efficient at killing S. mutans of biofilms and a useful approach in the treatment of dental plaque-related diseases.  相似文献   

12.
通过原位强碱诱导下的脱氯化氢缩合聚合法制备了一系列不同纳米TiO2含量的聚(2-甲氧基-5-辛氧基)对苯乙炔/纳米二氧化钛(PMOCOPV/TiO2)光电复合材料。红外光谱和拉曼光谱证实了在纳米TiO2表面的包覆层为PMOCOPV。紫外-可见吸收光谱表明随着TiO2含量的增加PMOCOPV/TiO2纳米复合材料的吸收强度提高。高分辨透射电镜观察发现PMOCOPV/TiO2是具有核-壳结构的纳米复合粒子,直径约30 nm,其中PMOCOPV包覆层的厚度约为8~10 nm。荧光光谱研究表明,PMOCOPV/TiO2纳米复合材料的最大发射波长随着TiO2含量的增加发生红移,荧光寿命约为1 ns,且随着TiO2含量的增加荧光强度和荧光寿命得到显著提高,并通过PMOCOPV/TiO2纳米复合材料中的激子离化和电荷传输过程以及复合材料中的电势能级探讨了PMOCOPV/TiO2的荧光量子效率和荧光强度增加的机理。  相似文献   

13.
In this paper, an Au/Ag bimetallic hollow nanostructure was obtained by using SiO2 nanospheres as sacrificial templates. The nanostructure was fabricated via a three steps method. SiO2@Au nanospheres were first synthesized by the layer-by-layer technique, and then they were coated with a layer of Ag particles, finally, the Au/Ag bimetallic hollow nanospheres were obtained by dissolution of the SiO2 core by exposure in HF solution. Several characterizations, such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and UV visible absorption spectroscopy were used to investigate the prepared nanostructures. The effectiveness of these Au/Ag bimetallic hollow nanospheres as substrates toward surface-enhanced Raman scattering (SERS) detection was evaluated by using rhodamine 6G (R6G) as a probe molecule. We show that such Au/Ag bimetallic hollow nanospheres structure films which consisting of larger interconnected aggregates are highly desirable as SERS substrates in terms of high Raman intensity enhancement. The Au/Ag bimetallic hollow nanostructured aggregate, interconnected nanostructured aggregate and nanoscale roughness are important factors responsible for this large SERS enhancement ability.  相似文献   

14.
A core-shell nanocomposite (CdS/TiO(2)) was synthesized at relatively low temperature (70°C) with small particle sizes (~11 nm). First, CdS nanoparticles were prepared by a combination of ultrasound and new micro-emulsion (O/W) without surfactant. Then the synthesized CdS was easily combined with TiO(2) under sonication. The formation of uniform surface layer of TiO(2) with depths of 0.75-1.1 nm on the CdS led to an increase of particle size. Ultrasonic irradiation can control the hydrolysis and condensation of titanium tetra-isopropoxide (TTIP) and the formation of TiO(2) shell around the CdS core. This technique avoids some of the problems that exist in conventional microemulsion synthesis such as the presence of different additives and calcinations. It was found that nanocomposite particles extend the optical absorption spectrum into the visible region in comparison with pure TiO(2) and pure CdS. In addition, a larger depth of TiO(2) led to a red-shift of the absorption band in nanocomposite. The characterization of nanocomposites has been studied by HRTEM, TEM, XRD, EDAX, BET and, UV-vis.  相似文献   

15.
光动力学疗法新型光敏剂的光谱特性研究   总被引:25,自引:1,他引:24  
实验研究了用于光动力学诊断和治疗的新型光敏剂二磺基二邻苯二甲酰亚胺甲基酞菁锌(ZnPcS2P)癌光啉(PsD-007)、血啉甲醚(HMME)以及早期应用于临床的血卟啉衍生物(HpD)分别在生理盐水和含10%人血清生理盐水中的光谱特性。结果表明:除ZnPcS2P2的最大吸收峰位于670nm之外,其余三种光敏剂在人血清环境中的最大吸收峰都位于405nm处,但与生理盐水环境相比索瑞(Soret)峰发生了12nm的红移。在波长为413和514.5nm光源激发下,HMME,HpD和PsD-007在人血清环境中的荧光发射峰都分别位于625和690nm,但413nm光源的激发效率比514.5nm光源高出3倍左右,而且HEEM的荧光激发效率最高,HpD次之,PsD-007最低。  相似文献   

16.
Ag@TiO2 core-shell structured particles of nano-size dimensions have been successfully prepared via a one-step way, which has proved quite effective in procuring stable colloids. Transmission electron microscopy (TEM) was employed to characterize the core size and the shell thickness, which typically were 20~40 nm and ~2 nm, respectively. X-ray diffraction (XRD) indicated the existence of silver. Optical absorption dependence on core size and synthetic temperature has been explored by UV–Vis absorption spectroscopy. Finally, the interesting titanium dioxide nanobubbles with silver core leached out by a unique means, were studied, which consequently proved the core-shell structure of the prepared nanoparticles, confirming the TEM observation.  相似文献   

17.
将传统半导体材料与金属微纳结构相结合,利用其表面等离激元共振效应,可有效地增强复合结构的光电转换效率,使其广泛地被用于光电化学和光电探测等领域.本文以氧化铝纳米管为模板,采用原子层沉积技术制备出高有序的TiO2纳米管,并通过电子束热蒸发技术在大孔径的纳米管薄膜中分别负载金、铝和双金属金/铝纳米颗粒,形成金属纳米颗粒/TiO2纳米管复合结构.研究结果表明,相对于纯TiO2纳米管,Au/TiO2复合纳米管在568 nm的可见光照射下,其光电流密度约有400%的提高;在365 nm紫外光照射下,Al/TiO2复合纳米管的光电流提高约50%;同时负载双金属Au和Al纳米颗粒的TiO2纳米管在整个紫外-可见光区域光电流均显著增强.  相似文献   

18.
Du SY  Li ZY 《Optics letters》2010,35(20):3402-3404
We propose a scheme to enhance near-UV band absorption of a rutile TiO(2) nanoparticle by placing Au nanoparticles in its neighborhood. The discrete-dipole approximation method was employed to calculate the absorption spectrum of pure rutile TiO(2) and that of TiO(2) mixed with Au nanoparticles. The results indicate that pure rutile TiO(2) has its maximum absorption located in the deep-UV band. With the existence of Au nanoparticles, a significant light harvesting effect occurs, and this maximum shifts to the near-UV band, where usual excitation wavelength falls.  相似文献   

19.
光动力疗法的疗效依赖于治疗过程中靶组织中光敏剂的含量或浓度 ,而药物在组织中的分布特性是受动物机体调控的 ,因此 ,同一个体不同组织对光敏剂吸收的时间特性需要同时进行检测才能排除个体之间的差异。建立了一套空间三通道激光诱导荧光同步检测装置 ,并用该装置研究了活体大耳白兔风湿性关节炎模型滑膜、软骨和皮肤对血啉甲醚吸收的时间特性。研究结果表明 ,炎性滑膜组织对血啉甲醚的吸收量远大于软骨和皮肤 ,这一差别在静脉给药即刻就很明显 ,在静脉给药后 2 0min内 ,滑膜中的光敏剂药物含量约为软骨和皮肤中的 6倍。因此 ,对于借助血啉甲醚 ,用光动力疗法治疗风湿性关节炎并采用体外照射治疗方案时 ,从注药即刻开始 ,前 2 0min左右进行光照治疗可能是较好的选择。  相似文献   

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