荧光共轭聚合物传感器的应用

介绍了共轭聚合物的荧光信号放大机理,综述了近年来作为传感器的荧光共轭聚合物的应用研究进展,以及共轭聚合物作为基材的传感器的种类、共轭聚合物在传感器方面面临的问题及研究方向。     

水相合成S-正辛基-5,5-二苯基-2-硫代海因的绿色工艺

以5,5-二苯基-2-硫代海因和溴代正辛烷为原料,在碱水溶液中相转移催化合成S-正辛基-5,5-二苯基-2-硫代海因,考察溴代正辛烷用量、氢氧化钾用量、相转移剂种类和用量以及反应时间对产率的影响。确定较佳工艺条件为：5,5-二苯基-2-硫代海因50 mmol,溴代正辛烷55 mmol,氢氧化钾50 mmol,十八叔胺0.2 g,水50 mL,回流反应4 h,可得到高纯度S-正辛基- 5,5- 二苯 基-2 -硫代海因,产率达85%。产品结构经IR、¹H NMR、13C NMR及MS进行了表征。     

5-取代-1-乙酰基-2-硫代海因衍生物的微波快速合成

微波辐射下,硫氰酸铵与a-氨基酸在乙酸酐和冰乙酸的混合溶剂中反应,快速合成了9种5-取代-1-乙酰基-2-硫代海因衍生物. 探讨了微波反应时间、微波反应温度、硫氰酸铵用量及乙酸酐用量对产率的影响,得到了最佳反应条件：a-氨基酸用量10 mmol,硫氰酸铵用量16 mmol,乙酸酐用量9 mL(冰乙酸用量1 mL),微波反应温度100℃,微波反应时间2 min. 与常规加热法相比,反应时间由30 min缩短到2 min,产率由55.2%~79.5%提高到85.0%~93.0%. 产物结构经1H-NMR, IR和元素分析验证.     

水溶性共轭聚合物在荧光传感器上的应用进展

水溶性共轭聚合物具有良好的光电性质和良好的水溶性,在传感器方面表现出诱人的应用前景,因此近年来关于它们的研究备受瞩目。本文主要概述近年来以水溶性共轭聚合物为基础的荧光传感器在金属离子、小分子以及生物大分子检测方面的应用进展。     

共轭聚合物在荧光化学传感器中的应用特征

综述了共轭聚合物作为传感材料在荧光化学传感器中的应用特征,着重就其良好的半导体性及灵敏性、高的摩尔吸光系数与荧光量子效率、传感信号放大功能以及良好的加工性能进行了介绍。此外,还对其发展方向和应用前景进行了展望。     

一种戊二醛-壳聚糖非共轭荧光聚合物传感器检测水样中汞离子

开发了一种新型、快速的荧光传感器用于水样品中Hg~(2+)的检测。合成了一种戊二醛-壳聚糖非共轭荧光聚合物(GCPF),在370 nm波长激发下,于455 nm波长处产生荧光。研究发现,汞离子(Hg~(2+))的存在能使GCPF荧光被猝灭。传感器对Hg~(2+)的检测线性范围是0. 8～30μmol/L,检测限为85 nmol/L。该方法灵敏度高、线性范围宽、成本较低、操作方便、响应迅速(约1 min),对其他金属离子具有很好的选择性。将其应用于实际水样中Hg~(2+)检测时也得到了令人满意的结果。     

荧光共轭聚合物在炸药探测中的应用

概述了炸药和炸药探测技术的种类以及荧光共轭聚合物的化学传感原理,综述了荧光共轭聚合物传感技术在炸药探测方面的应用研究进展以及取得的主要成就,并对其存在的主要问题做了简要的说明。提出高灵敏度、高信息负载度、低误判率的专用彩色聚合物炸药探测器件,在未来器件中有着更大的发展前景。     

荧光共轭聚合物的结构设计与合成方法研究

荧光共轭聚合物既有机小分子荧光材料优良的光学品质,又具有高分子材料优越的可加工性能,成为了荧光材料的研究热点。因此,荧光共轭聚合物在开发新型化学、生物及爆炸物传感器等方面具有非常广阔的应用前景。本文介绍了几种典型的荧光聚合物,重点介绍了聚合物中荧光发色团的合成,从分子结构设计、应用及优缺点等方面对各种合成方法进行阐述比较。并且展望了今后荧光共轭聚合物的发展前景。     

2-二甲胺基-1-硫代磺酸钠基-3-硫代磺酸基丙烷的合成

以 1-二甲胺基 - 2 ,3 -二氯丙烷盐酸盐水溶液与硫代硫酸钠为主要原料 ,合成制得 2 -二甲胺 - 1-硫代磺酸钠基 - 3-硫代磺酸基丙烷。先在 0～ 3℃ ,盐酸盐水溶液中加入定量NaOH制得氯化物 ,再进行硫代硫酸化反应。用正交设计试验法优选出硫代硫酸化反应最佳工艺条件为 :氯化物pH值 6 .8,反应温度 6 9℃ ,反应时间 3 .5h ,甲醇用量为每摩尔氯化物 6 0 0g,反应收率从目前工业生产的 85 .4%提高到 95 .8%。     

共轭聚合物在传感器上的应用

由于其特殊的光学和电子性质，共轭聚合物受到人们的广泛关注．共轭聚合物可以在各种传感器件中用作活性材料，例如：生物传感器；气体、湿度传感器；离子传感器；压力、温度传感器等．本文综述了共轭聚合物在传感器应用方面的一些新的进展．     

新的5-对羟基苄亚甲基-2-硫代-2,4-咪唑啉二酮苯磺酸酯的合成

以4-羟基苯甲醛和2-硫代乙内酰脲为原料高收率的合成了5-对羟基苄亚甲基-2-硫代-2,4-咪唑啉二酮,再将它与取代苯磺酰氯反应合成了标题化合物,它们的结构经1~HNMR、~(13)CNMR和元素分析确证.     

Ladder-like Polymer Brushes Containing Conjugated Poly(Propylenedioxythiophene) Chains

The high stability and conductivity of 3,4-disubstituted polythiophenes such as poly(3,4-ethylenedioxythiophene) (PEDOT) make them attractive candidates for commercial applications. However, next-generation nanoelectronic devices require novel macromolecular strategies for the precise synthesis of advanced polymer structures as well as their arrangement. In this report, we present a synthetic route to make ladder-like polymer brushes with poly(3,4-propylenedioxythiophene) (PProDOT)-conjugated chains. The brushes were prepared via a self-templating surface-initiated technique (ST-SIP) that combines the surface-initiated atom transfer radical polymerization (SI-ATRP) of bifunctional ProDOT-based monomers and subsequent oxidative polymerization of the pendant ProDOT groups in the parent brushes. The brushes prepared in this way were characterized by grazing-angle FTIR, XPS spectroscopy, and AFM. Steady-state and time-resolved photoluminescence measurements were used to extract the information about the structure and effective conjugation length of PProDOT-based chains. Stability tests performed in ambient conditions and under exposure to standardized solar light revealed the remarkable stability of the obtained materials.     

超氧阴离子自由基荧光探针的研究进展

超氧阴离子自由基(O 2-.)是生物体内重要的自由基之一,也是所有活性氧自由基的前体,可以转化为其它的活性氧自由基。近年来大量文献报道超氧阴离子自由基与生物体发生的炎症、衰老及癌症等重大疾病有密切关系,因此对其检测具有非常重要的科学意义。本文综述了有关超氧阴离子自由基荧光探针的设计、合成及其分析检测。     

基于萘酰亚胺为发光团的Zn2+荧光探针的合成与研究

设计合成了一种基于萘酰亚胺为发光团的Zn2+荧光探针.相对于其他常见金属离子,该探针对Zn2+具有较好的选择性.探针对Zn2的识别机理为Zn2+的加入导致C=N异构化受阻,荧光增强.探针对Zn2+的线性检出范围为0.3 ～2.0μmol/L,检出限为0.15 μmol/L.     

一种新型罗丹明类双通道荧光探针及其对Fe~(3+)和Cu~(2+)的选择性识别研究

以罗丹明B、水合肼和吡啶-2-甲醛为反应物,合成了一种新型的罗丹明类Fe~(3+)和Cu~(2+)双通道分子探针(Fluorescent probe,FP),并用核磁和质谱对其分子结构进行了表征。利用荧光分光光度计和紫外可见分光光度计研究了FP对Fe~(3+)、Cu~(2+)等14种金属离子的识别性能。研究结果表明,在V(CH_3OH)∶V(H_2O)=1∶1体系中,当选用荧光光谱分析时,探针FP对Fe~(3+)具有良好的选择性响应,且Fe~(3+)浓度在2~30μmol/L时,探针荧光强度与Fe~(3+)浓度呈线性关系,线性相关系数为0.998。当选用紫外可见光谱分析时,探针FP对Cu~(2+)具有很好的选择性响应,且当Cu~(2+)浓度为0~9μmol/L时,探针FP的吸光度与Cu~(2+)浓度呈线性关系,线性相关系数为0.999。     

Formation of Multicolor Nanogels Based on Cationic Polyfluorenes and Poly(methyl vinyl ether-alt-maleic monoethyl ester): Potential Use as pH-Responsive Fluorescent Drug Carriers

In this study, we employed the copolymer poly(methyl vinyl ether-alt-maleic monoethyl ester) (PMVEMA-Es) and three fluorene-based cationic conjugated polyelectrolytes to develop fluorescent nanoparticles with emission in the blue, green and red spectral regions. The size, Zeta Potential, polydispersity, morphology, time-stability and fluorescent properties of these nanoparticles were characterized, as well as the nature of the interaction between both PMVEMA-Es and fluorescent polyelectrolytes. Because PMVEMA-Es contains a carboxylic acid group in its structure, the effects of pH and ionic strength on the nanoparticles were also evaluated, finding that the size is responsive to pH and ionic strength, largely swelling at physiological pH and returning to their initial size at acidic pHs. Thus, the developed fluorescent nanoparticles can be categorized as pH-sensitive fluorescent nanogels, since they possess the properties of both pH-responsive hydrogels and nanoparticulate systems. Doxorubicin (DOX) was used as a model drug to show the capacity of the blue-emitting nanogels to hold drugs in acidic media and release them at physiological pH, from changes in the fluorescence properties of both nanoparticles and DOX. In addition, preliminary studies by super-resolution confocal microscopy were performed, regarding their potential use as image probes.     

A Lucifer‐Based Environment‐Sensitive Fluorescent PNA Probe for Imaging Poly(A) RNAs

Fluorescence‐based oligonucleotide (ON) hybridization probes greatly aid the detection and profiling of RNA sequences in cells. However, certain limitations such as target accessibility and hybridization efficiency in cellular environments hamper their broad application because RNAs can form complex and stable structures. In this context, we have developed a robust hybridization probe suitable for imaging RNA in cells by combining the properties of 1) a new microenvironment‐sensitive fluorescent nucleobase analogue, obtained by attaching the Lucifer chromophore ( 1,8‐naphthalimide) at the 5‐position of uracil, and 2) a peptide nucleic acid (PNA) capable of forming stable hybrids with RNA. The fluorescence of the PNA base analogue labeled with the Lucifer chromophore, when incorporated into PNA oligomers and hybridized to complementary and mismatched ONs, is highly responsive to its neighboring base environment. Notably, the PNA base reports the presence of an adenine repeat in an RNA ON with reasonable enhancement in fluorescence. This feature of the emissive analogue enabled the construction of a poly(T) PNA probe for the efficient visualization of polyadenylated [poly(A)] RNAs in cells—poly(A) being an important motif that plays vital roles in the lifecycle of many types of RNA. Our results demonstrate that such responsive fluorescent nucleobase analogues, when judiciously placed in PNA oligomers, could generate useful hybridization probes to detect nucleic acid sequences in cells and also to image them.     

基于喹啉Zn2 荧光探针的合成和性能研究

以邻氨基苯甲酸和咔唑为原料,经多步反应得到3-(2-(8-(1H-苯并咪唑-2-基)喹啉-2-基)乙烯基)-9-苯甲基-9H-咔唑(探针L),并通过1H NMR,13C NMR,MS对其进行了结构表征。荧光光谱法研究表明,该探针对Zn2+的选择性好,抗干扰能力较强,50 s内响应,在pH值为5~9范围内对pH值不敏感。探针L与Zn2+的荧光强度与Zn2+浓度(0～1.6×10-5 mol/L)呈现良好的线性关系,相关系数R2=0.99866,检测限为6.69×10-8 mol/L。Job’s曲线、荧光滴定实验和ESI-MS谱分析表明探针L与Zn2+的络合比为1:1。