水相分子印迹光子晶体水凝胶传感器检测尿液中的痕量吗啡

结合水相分子印迹和光子晶体技术构建了吗啡分子印迹光子晶体水凝胶传感器,并成功用于生物样品中痕量吗啡的筛查.以吗啡为印迹模板,甲基丙烯酸为单体,乙二醇二甲基丙烯酸甲酯为交联剂,填充至二氧化硅光子晶体模板孔隙中进行共价型分子印迹聚合,在1％ HF溶液中除去光子晶体模板,并洗脱印迹模板分子,即可得到具有目标分子传感功能的分子印迹光子晶体水凝胶传感器.此传感器在水相环境中对吗啡分子的识别能力良好,可以在不需要标记的情况下,将目标分子的识别转变为衍射峰的位移,该光学信号通过传感器颜色的变化表现出来,吗啡浓度由10 pg/mL增加到1μg/mL过程中,衍射峰最大偏移达到38 nm,并且抗干扰能力强,检出限为0.1 μg/L,响应时间为40 s,可以重复使用.此检测平台不需要对样品进行处理,便可准确、灵敏、快速地检测复杂样品中的目标分析物.     

尼泊金乙酯分子印迹固相萃取小柱的研制及应用

研制了一种对尼泊金乙酯具有特异性识别性能的分子印迹固相萃取小柱。用本体聚合法制备尼泊金乙酯分子印迹聚合物,通过静态平衡吸附实验及固相萃取实验表征其固相萃取性能,并结合UV法对滴眼液中的尼泊金乙酯进行测定。结果显示,尼泊金乙酯模板聚合物的吸附能力强于空白聚合物;印迹固相萃取柱对尼泊金乙酯标准溶液(0.04mmol/L)一...     

分子印迹光子晶体阵列传感器的构建及其对双酚A和双氰胺的检测

将分子印迹技术与光子晶体材料结合,构建了基于反蛋白石结构分子印迹光子晶体聚合物(MIPPs)的阵列传感器,用于微量双酚A(BPA)和双氰胺(DCD)的特异识别检测。对分子印迹聚合体系、模板分子洗脱条件进行了优化,当单体与模板分子摩尔比分别为1∶2和1∶4时,制备的BPA和DCD MIPPs的吸附效果最好,衍射峰位移最大。通过吸附动力学和吸附等温线实验考察了构建的传感器阵列的吸附性能。结果表明,构建的MIPPs传感器对BPA和DCD的响应时间分别为2.5和4.0 min,衍射峰位移量与BPA和DCD在其浓度分别为0.1～5.0μg/L和0.1～10.0μg/L范围时具有良好的线性关系,最大衍射峰位移量分别为39和31 nm,检出限分别为0.051和0.038μg/L;而非印迹光子晶体膜的衍射峰位移不明显,表明制备的MIPPs阵列具有选择特异性。实际样品测定结果表明,此MIPPs阵列传感器对实际样品中的目标物有明显的光学信号响应,可以快速、灵敏、选择性地检测环境水样中的目标分析物。     

尼泊金乙酯分子印迹膜电化学传感器的制备

以邻苯二胺为功能单体,尼泊金乙酯为模板分子,通过电化学聚合在玻碳电极表面制备了尼泊金乙酯分子印迹膜,采用循环伏安法及方波伏安法,以K3[Fe(CN)6]为电活性探针,建立了间接测定尼泊金乙酯的分析方法。实验结果表明,制备的分子印迹膜电化学传感器对尼泊金乙酯具有较高的选择性和灵敏度,测定尼泊金乙脂的线性范围为2.5×10-6~1.0×10-5 mol/L,检出限为8.61×10-8 mol/L。     

糖蛋白印迹二维光子晶体水凝胶传感器的构建

制备了一种特异性识别糖蛋白的二维光子晶体分子印迹水凝胶。以刀豆蛋白A(Con A)为模板分子,甲叉双丙烯酰胺(MBA)为交联剂,丙烯酰胺(AAm)与4-乙烯基苯硼酸为功能单体,N,N,N′,N′-四甲基乙二胺(TEMED)为引发剂,过硫酸铵(APS)为催化剂,在聚苯乙烯二维光子晶体(PC)表面产生聚合反应形成水凝胶,接着用10%的乙酸溶液洗脱模板分子,制备了可对Con A特异性识别的二维光子晶体分子印迹水凝胶(MIPs)传感器。结果表明,当MIPs的交联度为10%时,德拜环的直径变化最显著,对目标物的识别最灵敏。该传感器对Con A在0～0.5 mg/mL范围内具有良好的响应与识别能力,可用于目标物的富集和即时检测。同时,苯硼酸的引入,增加了印迹空穴的识别位点,进一步改善了印迹材料对糖类分子的特异识别性。该水凝胶传感器在卵清白蛋白(OVA)、牛血红蛋白(BHb)、溶菌酶(Lyz)、胰蛋白酶(Try)溶液中德拜环的直径变化远小于识别相同浓度的Con A引起的德拜环直径的变化,表现出良好的选择性。该方法操作简单,成本低廉,可重复使用,不需特殊仪器设备,可拓展到其它糖蛋白,实现糖类目标蛋白的...     

苯胺分子印迹光子晶体水凝胶传感器的研究

基于分子印迹与光子晶体技术,制备了一种高灵敏、特异性好的苯胺水凝胶光学传感器。以Stober法制作的SiO_2微球作为三维光子晶体模板,苯胺为印迹分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸甲酯为交联剂,2,2-偶氮二异丁腈为光引发剂,在紫外光下引发聚合,并在三氯甲烷(加入适量乙醇)中洗脱印迹分子,最终得到具有对苯胺分子有传感功能的分子印迹光子晶体水凝胶传感器。实验结果表明,该传感器对苯胺分子具有良好的识别能力,当苯胺的浓度从0增加到1×10~(-4)mol/L时,通过光谱仪检测出的吸收峰偏移了42 nm。此外,该传感器在苯胺的结构类似物甲基苯胺的缓冲液的响应位移明显较小,表明该传感器具有良好的选择性。     

分子印迹光子晶体传感芯片的制备及对邻苯二甲酸酯类化合物的检测

将光子晶体与分子印迹技术相结合,制备了一种反蛋白石结构的分子印迹光子晶体传感芯片,并将其应用于4种邻苯二甲酸酯类化合物的检测效果研究.分子印迹光子晶体传感芯片的制备过程包含3个步骤.首先,通过垂直沉降自组装方法制备SiO2蛋白石结构模版;随后,向蛋白石结构模板空隙中填充含有印迹分子邻苯二甲酸二异壬酯(DINP)的预聚液,引发光聚合;最后,移除SiO2结构模版及印迹分子,得到对邻苯二甲酸酯类化合物具有特异性识别功能的分子印迹光子晶体传感芯片.结果表明,传感芯片对待测物分子的识别过程可通过布拉格方程转换为可读的光学信号,当4种待测物浓度从1×10-5 mol/L增大到1 mol/L时,最大衍射峰位置发生20～40 nm的红移,且检测过程仅需6 min.检测芯片高度交联的聚合物结构令其具有较高的稳定性和重复利用性,5次检测后,芯片仍保持较好的传感性能.     

2,4,6-三氯酚分子印迹光子晶体水凝胶传感器的研究

以SiO2三维光子晶体为模板,2,4,6-三氯酚为印迹分子,甲醇为溶剂,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸甲酯为交联剂,通过紫外光引发聚合,在2%氢氟酸溶液中去除光子晶体模板,0.015 mol/L NaOH溶液中洗脱印迹分子,制得2,4,6-三氯酚检测用分子印迹光子晶体水凝胶传感器。结果表明,传感器对2,4,6-三氯酚具有良好的响应与识别能力,在2,4,6-三氯酚浓度由0增加到6×10-4 mol/L过程中,吸收峰红移31 nm;浓度继续增加,吸收峰开始发生蓝移;当浓度增加到1×10-3 mol/L时,吸收峰蓝移56 nm,响应时间仅需要30 min。2,4,6-三氯酚分子印迹光子晶体水凝胶传感器具有高灵敏、高选择、易操作等优点,可实现对2,4,6-三氯酚的裸眼检测。     

三聚氰胺分子印迹光子晶体水凝胶膜传感器的制备及应用

该文将光子晶体与分子印迹技术结合，制备了分子印迹光子晶体水凝胶膜（MIPHs）作为光学传感器，用于样品中三聚氰胺的快速识别检测。以三聚氰胺为模板分子，通过垂直沉降自组装、填充聚合、去除模板3个步骤，制备得到了反蛋白石结构的三聚氰胺MIPHs。扫描电子显微镜的形貌表征表明，MIPHs具有高度有序的三维大孔结构。该MIPHs作为光学传感器可以将三聚氰胺的分子特异识别过程转换成光学信号，在对目标分析物分析时具有选择性高、响应快、灵敏度高的优点。此外，可以根据MIPHs的颜色变化利用图像软件分析或裸眼识别的方式实现目标分析物快速识别。实验结果表明，在最优条件下，三聚氰胺浓度为10^-11~10^-6mol/L时，MIPHs的布拉格衍射峰位移从563 nm红移到608 nm，而对三聚氰胺的结构类似物没有明显响应。     

应用门效应-分子印迹传感器测定盐酸强力霉素

利用邻苯二胺作为功能单体,盐酸强力霉素为模板分子,用电聚合的方法在金电极表面制备出对盐酸强力霉素可进行特异识别的分子印迹膜,利用门控制原理对盐酸强力霉素进行测定。表征了分子印迹膜的性能、印迹效应;试验了测定条件;该传感器对盐酸强力霉素的检测具有良好的选择性。盐酸强力霉素的浓度在2.0×10-9～1.0×10-7mol/L范围内与响应电流呈线性关系,检出限达8.7×10-10mol/L,低于现有分析方法。该传感器可用于鱼肉样品中盐酸强力霉素的检测,回收率在96.6%～103.1%。     

乙基膦酸分子印迹光子晶体传感器的研究

本研究结合光子晶体与分子印迹技术,制备了一种新颖有机磷毒剂光学传感器——三维分子印迹光子晶体(3D-MIPCs)凝胶膜.采用聚甲基丙烯酸甲酯胶体小球为光子晶体自组装阵列模板,以甲基丙烯酸羟乙酯和N-异丙基丙烯酰胺为混合单体,乙二醇二甲基丙烯酸酯和N,N-亚甲基双丙烯酰胺为混合交联剂,正辛醇和乙腈混合溶液为溶剂,光聚得到印迹聚合物.该材料对乙基膦酸响应速度快、选择性高,其对目标分子的识别作用会导致衍射光谱图的改变.随着在EPA浓度从0.5 mmol/L增加到1.5 mmol/L的过程中,反射峰强度逐渐降低,降幅达到10％,并伴随明显红移.该材料为乙基膦酸检测提供了新的思路,在神经毒剂检测及监控等领域有应用前景.     

Introduction of a planar defect in a molecularly imprinted photonic crystal sensor for the detection of bisphenol A

This paper reports the preparation of a molecularly imprinted inverse opal hydrogel containing a 2D defect layer, by combining the Langmuir-Blodgett technique and the photonic crystal template method. By coupling the exceptional characteristics of molecularly imprinted polymers, sensitive to the presence of a target molecule, and those of photonic crystals in a single device, we could obtain a defect-embedded imprinted photonic polymer consisting in a three-dimensional, highly-ordered and interconnected macroporous array, where nanocavities complementary to analytes in shape and binding sites are distributed. As a proof of concept, we prepared a three-dimensional macroporous array of poly(methacrylic acid) (PMAA) containing molecular imprints of bisphenol A (BPA) and a planar defect layer consisting in macropores of different size. The optical properties of the resulting inverse opal were investigated using reflection spectroscopy. The defect layer was shown to enhance the sensitivity of the photonic crystal material, opening new possibilities towards the development smart optical sensing devices.     

Molecularly imprinted photonic polymer as an optical sensor to detect chloramphenicol

An inverse opal photonic crystal sensor that could specifically detect chloramphenicol (CAP) in a label-free way was introduced in the current research. A colloidal crystal template was first prepared from monodisperse SiO(2) nanospheres. Precursors with different compositions were infused into the void spaces of the respective templates and aggregated. The template and the imprinted CAP were removed, and a molecularly imprinted photonic polymer (MIPP) with numerous nanocavities derived from the SiO(2) template was prepared. The MIPP could specifically recognize the target CAP. The results showed that the embedding and transporting of CAP could change the reflection peak intensity of the MIPP. The MIPP exhibited good responsiveness, with a detection range from 1 ng mL(-1) to 1 μg mL(-1) of CAP. The MIPP response time was 8 min upon its addition to CAP at a concentration of 10 ng mL(-1), which is shorter than that of other methods. After repeated use, the MIPP maintained a good performance and detection capacity. Thus, the results prove that the novel sensor could specifically detect CAP in a simple, time-saving, and low-cost manner.     

Molecularly Imprinted Photonic Polymers as Sensing Elements for the Creation of Cross‐Reactive Sensor Arrays

By combining molecular imprinting and colloidal crystal templating, molecularly imprinted inverse‐opal photonic polymers (MIPPs) acting as sensing elements have been exploited to create sensor arrays for the first time. With this new strategy, abundant sensing elements with differential sensing abilities were easily accessible. Because of the unique hierarchical porous structure integrated in each sensing element, high sensitivity and selectivity, fast response and self‐reporting (label‐free) detection could be simultaneously achieved. All these fascinating features indicate that MIPPs are ideal sensing elements for creating sensor arrays. By integrating the individual sensing elements on a substrate, the formed array chip delivers better portability and high‐throughput capability. As a demonstration, six kinds of contaminants were selected as analytes. The detection and discrimination of these analytes and even their mixtures in a wide range of concentrations, particularly trace amounts of analyte against a high background of other components, could be achieved, indicating the powerful capability of MIPPs‐based sensor array for sensing. These results suggest that the described strategy opens a new route for sensor array creation and should find important applications in a wide range of areas.     

基于光子晶体带边效应的表面增强拉曼基底

将光子晶体的带边效应与金纳米粒子的拉曼散射增强作用相结合,制备了一种新型光子晶体表面增强拉曼散射基底(PC-AuNPs),利用罗丹明B(RhB)作为报告分子,对所得基底性能进行检测.PC-AuNPs基底的制备包括3个步骤:在SiO2微球表面修饰氨基,再通过垂直沉降自组装得到蛋白石结构光子晶体(PC), 最后, 在光子晶体表面负载金纳米粒子(AuNPs).结果表明,光子晶体的带隙范围及AuNPs的负载量直接影响了PC-AuNPs基底的检测效果;以所得的PC-AuNPs基底测定RhB分子,其拉曼散射特征峰强度与浓度对数值呈现良好的线性关系,线性方程为I=1711lg[RhB(mol/L)]+15244,线性相关系数R2=0.9994,检出限为1×10-8 mol/L,表明此PC-AuNPs基底可用于目标物的定性及定量检测.本方法提高了传统拉曼散射光谱检测灵敏度,操作简单,具有良好的重现性,可为其它新型检测基底的制备提供.     

Luminescent core-shell photonic crystals from poly(phenylene ethynylene) coated silica spheres

We describe the preparation and characterization of a photonic crystal filled with a luminescent conjugated polyelectrolyte, sulfonated poly(phenylene ethynylene). The conjugated polymer was coated onto the nanospheres by the layer-by-layer method and assembled directly into a fluorescent opal structure avoiding the defects associated with post-filling schemes. These structures exhibit strong angle-dependent luminescent properties. By using multiple layers, we further demonstrate control over the emissive bands of the opal.     

Application of a novel electrosynthesized polydopamine-imprinted film to the capacitive sensing of nicotine

The application of novel electrosynthesized polydopamine (PDA)-imprinted film as a recognition element for the capacitive sensing of nicotine is reported. The PDA-imprinted film was electropolymerized directly on the gold electrode surface in the presence of nicotine without an additional self-assembled thiol sublayer. The compact PDA film has various functional groups that aid the imprinting procedure. Furthermore, the film shows good capacitive response since it is insulating in nature and ultrathin. The sensor’s linear response range for nicotine was between 1–25 μmol L⁻¹, with a detection limit of 0.5 μmol L⁻¹. The proposed molecularly imprinted polymer capacitive (MIPC) sensor exhibited good selectivity for nicotine. The reproducibility and repeatability of the MIPC senor were all found to be satisfactory. The results from sample analysis confirmed the applicability of the MIPC sensor to quantitative analysis.     

Dry etching of colloidal crystal films

Two types of non-close-packed colloidal crystal films were prepared by etching the films made of polystyrene nanospheres using a hyperthermal neutral beam of oxygen gas. Etching without sintering above glass transition temperature of the polymer particles resulted in the non-close-packed structure of the nanospheres, in which polystyrene nanospheres in different lattice planes touched each other due to the reduction in the size of the nanospheres that occurred during the etching process. In contrast, a different non-close-packed structure with inter-connecting networks between etched nanospheres was generated by annealing of the colloidal crystal and a subsequent etching process. The photonic bandgap could be tuned during this dry etching of colloidal photonic crystals. This connected open structure could be used as a template for a silica inverse opal by chemical vapor deposition. An alternative dry etching process, reactive ion etching, mainly affected the morphology of particles near the top surface, and only a slight change in the stop band position of the colloidal crystal film was observed.     

Responsive Inverse Opal Hydrogels for the Sensing of Macromolecules

Dual responsive inverse opal hydrogels were designed as autonomous sensor systems for (bio)macromolecules, exploiting the analyte‐induced modulation of the opal’s structural color. The systems that are based on oligo(ethylene glycol) macromonomers additionally incorporate comonomers with various recognition units. They combine a coil‐to‐globule collapse transition of the LCST type with sensitivity of the transition temperature toward molecular recognition processes. This enables the specific detection of macromolecular analytes, such as glycopolymers and proteins, by simple optical methods. While the inverse opal structure assists the effective diffusion even of large analytes into the photonic crystal, the stimulus responsiveness gives rise to strong shifts of the optical Bragg peak of more than 100 nm upon analyte binding at a given temperature. The systems’ design provides a versatile platform for the development of easy‐to‐use, fast, and low‐cost sensors for pathogens.