Poly tetra porphyrin

T. Yirgili, D. Lidzey, and D.D.C. Bradley, Efficient energy transfer from blue to red in tetra-porphyrin-doped poly(9,9-dioctylfluorene) light-emitting diodes, Adv. Mater., 12 58-62, 2000. 

An imprinted poly[tetra(o-aminophenyl)porphyrin] film, deposited on a carbon fibre microelectrode by electropolymerization, was used for selective determination of dopamine [208] in the potential range of —0.15 to 1.0 V. This chemosensor has been used successfully for dopamine determination in brain tissue samples. The dopamine linear concentration range extended from 10 6 to 10-4 M with LOD of 0.3 pM. However, this LOD value is very high compared to that of the dopamine voltammetric detection using polyaminophenol MIPs prepared by electropolymerization [209]. Dopamine was determined by CV and DPV at concentrations ranging from 2 x 10 s to 0.25 x 10 6 M with LOD of 1.98 nM. This LOD value is lower than that of PM dopamine detection [133]. 

Tetra(o-aminophenyl)porphyrin, H-Co-Nl TPP, can for the purpose of electrochemical polymerization be simplistically viewed as four aniline molecules with a common porphyrin substituent, and one expects that their oxidation should form a "poly(aniline)" matrix with embedded porphyrin sites. The pattern of cyclic voltammetric oxidative ECP (1) of this functionalized metal complex is shown in Fig. 2A. The growing current-potential envelope represents accumulation of a polymer film that is electroactive and conducts electrons at the potentials needed to continuously oxidize fresh monomer that diffuses in from the bulk solution. If the film were not fully electroactive at this potential, since the film is a dense membrane barrier that prevents monomer from reaching the electrode, film growth would soon cease and the electrode would become passified. This was the case for the phenolically substituted porphyrin in Fig. 1. 

Other supramolecular structures such as dendrimers have also been synthesized with zinc-containing porphyrins. Sixteen free base and sixteen zinc porphyrin units were added at the fifth generation of dendritic poly(L-lysine) and intramolecular fluorescence energy transfer was observed.823 Assembly of supramolecular arrays in the solid state has been achieved with the incorporation of an amide group for hydrogen bonding. Zinc meso-tetra(4-amidophenyl)porphyrin... 

Using a typical poly (vinyl chloride) (PVC)-based membrane with different ionophores - Zn-bis(2,4,4-trimethylpen-tyl) dithiophosphinic acid complex [450], protoporphyrin IX dimethyl ester [451], porphyrin derivative [452] and hemato-porphyrin IX [453], tetra(2-aminophenyl) porphyrin [454], cryptands [455, 456], 12-crown-4 [457], benzo-substituted macro-cyclic diamide [458], 5,6,14,15-dibenzo-l, 4-dioxa-8,l 2, diazacyclopentadecane-5,14-diene [459], and (A-[(ethyl-l-pyrrolidinyl-2 -methyl) ] methoxy-2-sulfamoyl-5 -benza-mide [460] - the sensors for zinc ions were prepared and investigated. The armed macrocycle, 5,7,7,12,14,14-hexamethyl-1,4,8,11 -tetraazacyclo tetradeca-4,11 -diene dihydrogen perchlorate was used for the preparation of polystyrene-based Zn(II)-sensitive electrode [461]. 

Some papers have appeared that deal with the use of electrodes whose surfaces are modified with materials suitable for the catalytic reduction of halogenated organic compounds. Kerr and coworkers [408] employed a platinum electrode coated with poly-/7-nitrostyrene for the catalytic reduction of l,2-dibromo-l,2-diphenylethane. Catalytic reduction of 1,2-dibromo-l,2-diphenylethane, 1,2-dibromophenylethane, and 1,2-dibromopropane has been achieved with an electrode coated with covalently immobilized cobalt(II) or copper(II) tetraphenylporphyrin [409]. Carbon electrodes modified with /nc50-tetra(/7-aminophenyl)porphyrinatoiron(III) can be used for the catalytic reduction of benzyl bromide, triphenylmethyl bromide, and hexachloroethane when the surface-bound porphyrin is in the Fe(T) state [410]. Metal phthalocyanine-containing films on pyrolytic graphite have been utilized for the catalytic reduction of P anj -1,2-dibromocyclohexane and trichloroacetic acid [411], and copper and nickel phthalocyanines adsorbed onto carbon promote the catalytic reduction of 1,2-dibromobutane, n-<7/ 5-l,2-dibromocyclohexane, and trichloroacetic acid in bicontinuous microemulsions [412]. When carbon electrodes coated with anodically polymerized films of nickel(Il) salen are cathodically polarized to generate nickel(I) sites, it is possible to carry out the catalytic reduction of iodoethane and 2-iodopropane [29] and the reductive intramolecular cyclizations of 1,3-dibromopropane and of 1,4-dibromo- and 1,4-diiodobutane [413]. A volume edited by Murray [414] contains a valuable set of review chapters by experts in the field of chemically modified electrodes. 

AQS = Anthraquinone-2-sulfonic acid M(TPS) = metal tetrasulfophthalocyanine BPS = bathephenanthroline disulfonic acid M(TPPS) = metal tetra(4-sulfophenyl)porphyrin PVSK = potassium poly(vinylsulfate) PSSNa = sodium poly(styrene sulfonate) Nafion = Salt of sulfonated and Wghly fluorinated polymer (trademark of Du Pont). 

Umasankar Y, Shie J-W, Chen S-M. Electrocatalytic activity of oxygen and hydrogen peroxide reduction at Poly(iron tetra(o-aminophenyl)porphyrin) coated multiwalled carbon nanotube composite film. J Electrochem Soc 2009 156 K238—44. 

HCl Optochemical 5,10,15,20-Tetra (40-alkoxyphenyl) porphyrin [TP(OR)PH,] embedded in poly(hexyl acrylate), poly(hexylmethacrylate), poly(butyl methacrylate) Reversibly sensitive to sub-ppm levels of HCl... 

Electrochemical polymerization offers particular advantages in that polymerized porphyrins can form electroactive, adherent and stable films on solid electrodes. Oxidative electropolymerization of several porphyrins and metalloporphyrins have been reported . Special focus has been placed on amino-substituted porphyrins due to the propensity of aniline to form electroactive polymers. Murray et al. reported on the electropolymerization of tetrakis(o-aminophenyl)porphyrin and several para-, ortho-, and meta-substituted tetrakis(aminophenyl)porphyrins with Co as a central metal s. They found that poly-Co(o-NH2)TPP films are effective catalysts for the electroreduction of oxygen in aqueous solution. Metalloporphyrin films on solid electrodes have been mainly characterized by voltammetry and resonsance Raman spectroscopy. The electrochemistry of ruthenium paradiethylamino substituted tetraphenylporphyrins recently have been investigated . This study reports the ac impedance and UV-visible reflectance spectroscopic studies of paradiethylamino substituted tetra-phenylporphyrin films formed via an oxidative electropolymerization process. 

The principles of chemical recognition have been widely used in analytical chemistry for the development of selective sensing devices. The recognition properties of several ionophores have been exploited to enable the design of advanced materials suitable for the preparation of fiber optic and potentiometric sensors. Specifically, sensors were prepaid by electrochemically growing poly[Co(II)tetra(oamino-phenyl)porphyrin] and poly[Co(II)tetra(p-hydroxyphenyl)porphyrin] on glassy carbon electrodes and indium(tin) oxide (TTO) sUdes. 

Another porphyrin derivative that was used for sensor development is Co(II)tetra(p-hydroxyphenyl)porphym [Co(p-OH)TPP] (Figure 1) (40), Using cyclic voltammetry to electropolymerize the monomer on assy carbon electrodes, a pH-sensitive poly[Co(p-OH)TPP] film was prepared. The pH response of tiiese electrodes has been characterized, with a typical pH calibration curve shown in Figure 3. The poly[Co(p-OH)TPP] electrodes have near-Nemstian slopes (-52 to -54 mV/pH) and linear response from pH 2 to 12. 

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