表面增强拉曼散射在癌症检测中的应用进展

表面增强拉曼散射(Surface-Enhanced Raman Scattering,SERS)由于特异性强、灵敏度高,在生物医学领域有着广泛的应用。癌症是目前人类健康的主要杀手之一,及时的诊断与治疗是提高癌症患者生存率的最佳方式。SERS光谱能够准确给出被检测的癌细胞分子层面的信息,运用表面增强拉曼散射技术准确检测癌症成为生命科学和纳米材料领域研究的热点。本文对表面增强拉曼散射原理及在癌症检测方面最新的研究进展进行了综述。     

表面增强拉曼散射基底的研究进展

表面增强拉曼光谱(SERS)由于其高的灵敏度、抗干扰能力强等优点,被广泛应用在表面科学、分析化学、物理学等领域,是研究表面和界面过程的重要工具,是定性鉴定化学组成相近化合物的有力手段.因此,高品质、高活性的SERS基底一直是科研工作者们追求和研究的重点.本文对SERS活性基底的发展进行了介绍,从金、银金属纳米粒子作为基底的拉曼效应的科学研究,又进一步总结了非金属纳米粒子ZnO、TiO₂、ZnS、Cu₂O、CdTe、CdS等SERS基底.今后,将贵金属与半导体纳米材料复合将是SERS基底的研究热点.SERS光谱目前可以在液相色谱分析的检测器、医学检测仪器、刑侦分析检测等众多领域得到应用.     

表面增强拉曼光谱基底研究进展

表面增强拉曼光谱(SERS)由于具有拉曼峰强、检测灵敏度高、能够无损分析等特点,在生物传感、表面吸附、储能、转化、文物等领域应用广泛,而制备出均匀分散并且高稳定性和重现性SERS基底是SERS技术的前提.对表面增强拉曼光谱技术的基底以及机理进行了综述.     

表面增强拉曼光谱在农药残留检测中的应用

食品中农药残留的检测,对于预防或减少农药残留的危害至关重要。表面增强拉曼光谱以其超灵敏度、可无损检测和分子指纹能力优异而被应用于食品安全检测的相关研究。综述了表面增强拉曼光谱应用于食品农药残留检测中的最新进展。希望能为大家在食品安全、环境监测和农业保护等各个领域的应用提供明确的参考。     

Ag/双晶TiO_2作为表面增强拉曼散射基底的性能研究

通过化学还原法将Ag纳米粒子担载到锐钛/TiO2(B)双晶材料上,并将其作为表面增强拉曼散射(SERS)基底,用于有机探针分子4-巯基苯甲酸的痕量检测。研究表明:双晶氧化钛特殊的能带结构有利于光响应过程中电子-空穴的定向转移,从而比纯锐钛矿具有更优异的电子转移能力,因此能够得到更佳的SERS性能。这种现象表明,双晶氧化钛材料是SERS技术应用到检测领域的理想载体。     

疏水性钯纳米团簇的合成及其作为表面增强拉曼散射基底的应用

以醋酸钯为前体、有机氢硅烷为还原剂开发了一种简单温和的疏水性钯纳米颗粒制备方法。通过调节前体、保护剂和还原剂的配比,在氯仿溶液中室温条件下合成了疏水性的钯纳米团簇和钯纳米球。运用透射电子显微镜（TEM）、X射线衍射（XRD）、光学接触角测试仪、循环伏安法（CV）、表面增强拉曼光谱（SERS）对这两种钯纳米材料进行了测试表征。TEM观察表明这两种钯纳米材料粒径分布均匀,分散性良好。接触角测试表明钯纳米团簇与钯纳米球均具有疏水性。CV测定结果显示这两种钯纳米材料具有良好的电催化稳定性,钯纳米团簇比钯纳米球对乙醇氧化具有更突出的电催化性能,表明钯纳米团簇结构稳定并具有更大的比表面积。SERS测试表明钯纳米团簇是一种优良的疏水性表面增强拉曼散射基底,利用这种基底对疏水性致癌物3,4-苯并芘和联苯胺进行了SERS快速检测,检测限为0.1mg/mL。     

表面增强拉曼散射及其在缓蚀剂研究中的应用

表面增强拉曼散射技术作为一种提供分子结构信息的分析手段,具有广泛的应用前景。综述了表面增强拉曼散射技术的基本原理、特点和增强机理,介绍了表面增强拉曼散射技术在缓蚀剂研究中的应用,展望了表面增强拉曼散射技术的发展动态。     

Au/Pt合金气凝胶应用于表面增强拉曼散射

表面增强拉曼光谱(Surface-Enhanced Raman Scattering,SERS)被认为是最具实际应用前景的分析手段之一,在化学分析和污染物监测等众多领域都有着重要的潜在应用.目前对于SERS的研究,主要集中在制备一种新的SERS活性基底.作为气凝胶家族最年轻的成员之一,金属气凝胶(MAs)是一类新型、极...     

表面增强拉曼光谱在水体微塑料检测中的研究进展

近年来,水体微塑料（MPs）污染已经对人类健康产生重大威胁,建立快速、准确的微塑料检测方法十分必要。表面增强拉曼光谱作为一种无损快速检测技术,能提供分析物的“指纹”光谱,已经在环境检测领域得到了广泛应用。本文综述了SERS技术在水体微塑料检测中的应用,并进行了总结和展望。     

表面增强拉曼光谱法快速检测水产品中的孔雀石绿

基于表面增强拉曼光谱技术的便携式拉曼光谱仪运用于水产品养殖、运输过程水样中孔雀石绿的快速测定进行了研究.利用孔雀石绿位于432-437 cm-1,1166-1170 cm-1,1613-1617cm-1的拉曼光谱特征峰及其强度,对孔雀石绿进行定性及半定量的快速测定.检测限为5.0μg/L,常见含氮化合物尿素、亚硝酸钠以...     

Effects of substrate temperatures on improved surface-enhanced Raman scattering

In this work, electrochemical methods were used to prepare surface-enhanced Raman scattering (SERS)-active gold substrates to investigate the effect of substrate temperatures on improved SERS performances. The results indicate that the SERS enhancement capabilities are gradually raised from 25 °C to a maximum at 40 °C and monotonically decreased from 40 to 100 °C. The SERS of rhodamine 6G (R6G) adsorbed on the SERS-active substrate at 40 °C exhibits a higher intensity by 4-fold of magnitude, as compared with that of R6G adsorbed on the SERS-active substrate at 25 °C. Also, SERS of polypyrrole (PPy) deposited on the roughened Au substrate treated at 35 °C exhibits the highest intensity by 3-fold of magnitude, as compared with that of PPy deposited on the same roughened Au substrate at room temperature.     

Highly sensitive characteristic of surface enhanced Raman scattering for CuO/Au core/shell nanowires substrate

In this paper, we report a facile process to fabricate CuO/Au core/shell nanowires, where CuO core and Au shell were prepared by thermal oxidation and sputtering, respectively. The as-prepared CuO/Au nanowires are highly sensitive surface-enhanced-Raman-scattering (SERS) substrates, which can detect methylene blue down to a very low concentration of 10^?13 M. The major advantages of SERS substrates based on CuO/Au core/shell nanowires compared with others SERS substrates are the high sensitivity, uniformity, and purity due to the absence of any organic surfactants in the synthesis process.     

中药中农药残留前处理及检测方法的研究进展

对中药中农药残留分析常用的前处理方法和检测分析方法进行了总结,并着重介绍了近年发展起来的一些农药残留前处理方法和检测分析方法,这些方法可在中药材种植、加工、流通和使用过程中提供相应的检测方法,并使中药中农药残留的分析逐步快捷、精确、标准。     

气相色谱法测定姜中毒死蜱农药的残留量

介绍了用气相色谱法检测毒死蜱农药在姜中的残留方法,选用Agilent 6890N气相色谱仪,DB -1701和HP-5双柱法、火焰光度检测器(FPD)和电子俘获检测器(ECD)双检测器来定性,外标法定量,并用中性氧化铝柱净化样液,效果良好,节约检测成本,回收率为86.7%～93.4%,各项指标均满足有关要求。     

Surfactant-free and controllable synthesis of hierarchical platinum nanostructures and their comparative studies in electrocatalysis, surface-enhanced Raman scattering and surface wettability

Via electroless metal deposition, hierarchical platinum nanostructures, consisting of pinecone-like, microspherical and flower-like (assembling with staggered nanosheets) structures, are successfully synthesized on silicon substrates without introducing any template or surfactant, by controlling the concentration of platinum salt and pH value. Based on the observations of morphological evolutions, the mechanism for formation of the three hierarchical Pt nanostructures is proposed by manipulating the growth kinetics. Their properties of electrocatalysis, surface-enhanced Raman scattering (SERS) and surface wettability are comparatively studied. The electrochemical surface area follows the order of microspherical structures > pinecone-like structures > flower-like structures, while the enhancement factor of SERS is in the order of flower-like structures > pinecone-like structures > microspherical structures. After modification with fluoroalkylsilane, the surfaces of flower-like structures and pinecone-like structures become superhydrophobic (165° and 158° of CA, respectively), whereas the CA is only 122° for microspherical structures.     

QuECHERS-气相色谱法测定阿克苏特色农产品中的农残

建立QuECHERS-气相色谱法检测阿克苏特色农产品中25种农药残留量。样品用乙腈溶液振荡提取,QuECHERS净化,分别采用GC-ECD和GC-FPD检测,外标法定量。结果 25种农药在0.05～0.5mg/L线性关系良好,相关系数均大于0.990,加标浓度为0.05、0.1、0.2mg/kg,平均回收率在70.1～111.7%,相对标准偏差均小于15%,检出限在0.01～0.05mg/kg。该方法操作简便,准确可靠,稳定性强,适用于农产品中25种农药残留量的测定。     

Novel synthesis method and microstructure evolution of Ti3C2(OH)2/K2Ti8O17 nanocomposites as an effective surface enhanced Raman scattering substrate

In this paper, we have developed a mild and facile approach using KOH solution as etchants to corrode Ti₃SiC₂ at room temperature, fabricating novel Ti₃C₂(OH)₂/K₂Ti₈O₁₇ nanocomposites with open network structures and abundant surface functional groups. The as-produced products obtain the excellent surface enhanced Raman scattering (SERS) performance in the determination of crystal violet (CV), rhodamine 6G (R6G) and methylene blue (MB) dye molecules. The enhancement factors of the three can be calculated to be 3.98 × 10⁵, 1.78 × 10⁵ and 5.27 × 10⁵, and the Raman signals can be detected at the concentrations as low as 10^?6 M, 10^?8 M and 10^?6 M, respectively, suggesting the potential for reliable SERS substrates. In this regard, this work provides a new strategy for exploring and synthesizing MAX phase-derived nanomaterials as promising SERS substrates for high-sensitive molecular detection.     

Spinel structured MgAl2O4 nanoparticles as a low-cost and stable SERS substrate for rapid simultaneous detection of neurological drugs in biofluids

There is an urgent need for exploring reliable and low-cost techniques for simultaneous detection of neurological drugs to facilitate timely diagnosis and treatment of various neurological disorders. In this work, we demonstrate a low cost, one-step synthesis of spinel magnesium aluminate (MgAl₂O₄) nanoparticles as a chemically stable substrate for rapid, simultaneous detection of neurological drugs like nicotine, gabapentin, caffeine and carbamazepine in the biofluids via surface-enhanced Raman scattering (SERS) technique. The substrate exhibits a limit of detection (LOD) of 0.18 ng/mL, 0.78 μg/mL, 0.1 μg/mL and 0.81 μg/mL with an enhancement factor (EF) of 1.61 × 10⁷, 9.70 × 10⁷, 7.72 × 10⁷ and 1.52 × 10⁷ towards detection of nicotine, gabapentin, caffeine and carbamazepine, respectively with an accumulation time of 20 s. The substrate exhibits an excellent selectivity and a wide dynamic range of detection towards the drug molecules in presence of 0.1 mM of ascorbic acid (AA), NaCl, KCl, CaCl₂, urea, and glucose. This excellent performance can be ascribed to the interaction between the metallic sties of the MgAl₂O₄ cubic spinel structure and the drug molecules which leads to the resonance Raman scattering-like effect through the reconstruction of the energy bandgap closer to the photon energy of the excitation laser. Simultaneous recognition of drug molecules in the blood serum samples with reliable recovery percentages is also achieved using this platform thus, proving its efficacy for developing perovskite materials-based SERS detection useful in bioanalytical applications.     

果蔬中有机磷农药残留检测方法的研究进展

文章综述了果蔬中有机磷农药残留检测的方法。结论如下:色谱检测法检测时间相对稍长,但检测精度高,可为农药残留执法提供依据。光谱技术对样品前处理要求低,对环境污染小。农药残留快速检测法具有结果准确、污染少,成本低的优点。     

Characterization of crystallographic orientation and lattice disorder in hydroxyapatite thin films by Raman scattering

This report presents the way of evaluating the crystallographic orientation and crystallinity of hydroxyapatite (HAp) thin films by Raman scattering spectroscopy. According to the Raman selection rule, the symmetric stretching mode (ν₁) of P?O bonds in an isolated PO₄^3? units is Raman active, whereas the asymmetric stretching mode (ν₃) is not. Nevertheless, a weak ν₃ signal is usually observed in the Raman spectra of HAp powder crystals. We will show that the ν₃ signal is entirely absent for uniaxially oriented HAp films, whereas it appears in the case of randomly-oriented ones. This principle is feasible for discriminating the uniaxial orientation from a random one in HAp crystals. Another simple approach for evaluating crystallinity is exploiting the line width of the ν₁ PO₄^3? Raman signal. If the full-width at half maximum (FWHM) of the ν₁ signal is smaller than 7.4 cm^?1, the HAp crystal is uniaxially oriented in one direction, whereas if the FWHM value is larger than 7.4 cm^?1, the film is composed of randomly-oriented crystallites.