Electrochemiluminescence Enhanced by the Synergetic Effect of Porphyrin and Multi-walled Carbon Nanotubes for Uric Acid Detection

The design and exploration of efficient, stable and environmentally compatible organic emitters for an electrochemiluminescence (ECL) sensor is a promising topic. Herein, a novel environmentally-friendly luminophore, ZnBCBTP@MWCNTs, were fabricated via self-assembly of porphyrin molecules (ZnBCBTP) onto multi-walled carbon nanotubes (MWCNTs). The resulting luminophore ZnBCBTP@MWCNTs displayed not only the highly ECL property and but also the good accelerated electron mobility. Then, a label-free ECL biosensor based ZnBCBTP@MWCNTs was constructed for the ultrasensitive detection of uric acid. Excitingly, this proposed ECL biosensor performed a good linear relationship in the range of 0–300 μM with a low detection limit of 1.4 μM, thus offering another reliable and feasible sensing platform for clinical bioanalysis with good selectivity, stability, and repeatability.     

Multi-(phenylthio)porphyrinato Ni(II) compounds: Synthesis,structures and properties

A series of multi-(phenylthio)porphyrinato Ni(II) compounds were synthesized without the participation of transition metal catalysts. All of these products were well characterized by ¹H NMR, ¹³C NMR and HRMS. Structures of three typical compounds were further confirmed by X-ray single crystal diffraction. Remarkable red shifts were observed in UV–vis absorption spectra of multi-(phenylthio)porphyrinato Ni(II) compounds which meet well with the electrochemical data. DFT calculation indicates that the phenylthio groups have strong effects on the frontier orbitals of these molecules. The order of a_1u-like and a_2u-like orbitals mainly distributed in porphyrin moiety is often inversed in energy when multi-phenylthio groups are attached.     

Axial coordination of pyridyl-containing pentacenes to porphyrins

A pair of pentacenes that are functionalized in the 6-position with either a 3- or 4-pyridyl group via a triazole linker have been used to form complexes with a tetra(aryl)ruthenium(II) porphyrin through axial coordination. The pentacene–porphyrin dyads 5 and 6 have been structurally characterized through a combination of spectroscopic techniques. UV–vis spectroscopy shows that the absorption profiles of the two chromophores, the porphyrin and the pentacene, are complementary, providing absorptions throughout the UV and visible regions. While the dyads are reasonably stable in the solid state under ambient conditions they are, unfortunately, only stable in solution for hours when exposed to light and air.     

Synthesis and photophysical evaluations of β-fused uracil-porphyrin derivatives

New β-fused uracil-porphyrin conjugates were synthesized by the tetramerization of uracil-pyrroles under acidic conditions. Two different synthetic approaches were systematically studied in order to evaluate their efficiency, as well as the possibility to obtain a single regioisomer. Metallation effects were studied for aggregation in solution, and preliminary photophysical experiments were also performed in order to evaluate the potential of these new compounds.     

Optical Gas Sensor Fabrication Based on Porphyrin-Anchored Electrostatic Self-Assembly onto Tapered Optical Fibers

Tapered optical fibers with nano-assembled coatings of thicknesses of order tens of nanometres were used for the detection of ammonia gas. The film coating was composed of alternate layers of tetrakis-(4-sulfophenyl) porphine (TSPP) and poly(allylamine hydrochloride) (PAH), which were deposited using the electrostatic self-assembly process (ESA). Exposure of a PAH/TSPP nano-assembled non-adiabatic tapered optical fiber with a waist diameter of 10 µm to ammonia induced significant optical changes in the transmission spectrum of the optical fiber. The fiber optic sensor showed a linear sensitivity to the concentration of ammonia in the range of 10–100 ppm, with response and recovery times less than 100 and 240 sec, respectively. The 3σ limit of detection (LOD) was estimated to be ca. 2 ppm.     

Synthesis and investigation of photovoltaic properties for polymer semiconductors based on porphyrin compounds as light-harvesting units

We reported on two polymer semiconducting copolymers based on porphyrin compounds, poly[9,9-dioctylfluorene-co-5,15-bis(hexoxybenzyl)-10,20-bis(benzo-4-yl)porphyrin] (PFPor) and poly[9-(heptadecan-9-yl)carbazole-co-5,15-bis(hexoxybenzyl)-10,20-bis(benzo-4-yl)porphyrin] (PCPor), for use as organic photovoltaic materials. The thermal, optical, electrochemical, and photovoltaic properties of the two polymers were investigated. In addition, PC₆₁BM and PC₇₁BM were introduced as acceptor materials to confirm the acceptor effect in bulk heterojunction photovoltaic devices. Moreover, in order to establish acceptor effects, morphologies of polymer/PCBM blend films were analyzed through atomic force microscopy (AFM). PFPor and PCPor exhibited the best device performance with power conversion efficiencies (PCE) of 0.62% and 0.76%, respectively, upon the introduction of PC₇₁BM as the acceptor in the device where 86 wt.% of the PC₇₁BM was contained in the active layer (pol:PC₇₁BM = 1:6, w/w).     

Synthesis and characterization of new porphyrin/4-quinolone conjugates

New porphyrin/4-quinolone conjugates were synthesized from the Suzuki-Miyaura coupling reaction of a β-borylated porphyrin with bromo-4-quinolones containing N-ethyl and N-d-ribofuranosyl substituents. The use of electrospray ionization tandem mass spectrometry showed important information about the fragmentation pathways of the new compounds. It was possible to distinguish between those compounds with the porphyrin moiety linked at the 6-position of the quinolone unit from their 7-substituted isomers. The new compounds showed to be good singlet oxygen generators.     

二{[5,5'-10,20-二苯基-15-(4-吡啶基)卟啉]Zn(Ⅱ)]}丁二炔近红外荧光化合物的合成及光学性质

合成了具有近红外荧光特性的卟啉化合物二{[5,5’-10,20-二苯基-15-(4-吡啶基)卟啉]Zn(Ⅱ)]}丁二炔,通过核磁共振波谱和质谱对其结构进行了确认.通过紫外吸收光谱法测定了其光学性质,利用HWHR光学平台测定了化合物在近红外区激发产生的荧光,并通过动物组织模型评价其荧光深层次成像效果.结果表明,该化合物具...     

Noncovalent Assembly of Picket‐Fence Porphyrin on Carbon Nanotubes as Effective Peroxidase‐Like Catalysts for Detection of Hydrogen Peroxide in Beverages

A newly developed electrochemical sensor for determination of hydrogen peroxide (H₂O₂) in beverages using a water‐insoluble picket‐fence porphyrin (FeTpivPP) functionalized multiwalled carbon nanotubes (MWNTs) is demonstrated. Introduction of FeTpivPP on MWNTs led to enhanced electron transfer. As a new platform in electrochemical analysis, the resultant sensor showed excellent electrocatalytic activity toward the reduction of H₂O₂ due to the synergic effect between MWNTs and FeTpivPP, thus leading to highly sensitive amperometric sensing of H₂O₂ with a detection limit of 0.05 µmol L^?1. The developed method is successfully used to detect H₂O₂ in beverages and shows great promise for routine sensing applications.     

Electrospun Poly(acrylonitrile-co-acrylic acid) Nanofibrous Membranes for Catalase Immobilization:Effect of Porphyrin Filling on the Enzyme Activity

Porphyrin-filled nanofibrous membranes were facilely prepared by electrospinning of the mixtures of poly(acrylonitrile-co-acrylic acid)(PANCAA) and porphyrins. 5,10,15,20-Tetraphenylporphyrin(TPP) and its metal-loderivatives(ZnTPP and CuTPP) were studied as filling mediators for the immobilization of redox enzyme. Results indicate that the introduction of TPP, ZnTPP and CuTPP improves the retention activity of the immobilized catalase. Among these three porphyrins, the ZnTPP-filled PANCAA nanofibrous membra...