Reagentless amperometric detection of l-lactate on an enzyme-modified conducting copolymer poly(5-hydroxy-1,4-naphthoquinone-co-5-hydroxy-3-thioacetic acid-1,4-naphthoquinone)

Estudo da obtenção através de síntese eletroquímica de poliaminonaftalenos e poliaminoantracenos

“…Outra classe de PICs que estão recebendo atenção nos últimos anos é a dos poliaromáticos como os poliaminonaftalenos e poliaminonaftóis [2][3][4][5] , os poliaminoantrecenos [6,7] e as polinaftoquinonas [8,9] , que possuem sistemas aromáticos compostos por dois ou três anéis. Segundo Pham et al, para o caso dos poliaminonaftalenos (Figura 1) e poliaminonaftóis, o mecanismo de síntese e a estrutura do polímero obti-purificação.…”

“…Dentre estes destacam-se os que apresentam anéis aromáticos e ligações π alternadas. Dos PICs, a polianilina é um dos mais promissores, pois apresenta valores elevados de condutividade, propriedades eletrocrômicas, propriedades de troca iônica, um processo de síntese e dopagem simples, grande estabilidade quando exposta ao ambiente, além de ser obtida a partir de um monômero de baixo custo.Outra classe de PICs que estão recebendo atenção nos últimos anos é a dos poliaromáticos como os poliaminonaftalenos e poliaminonaftóis [2][3][4][5] , os poliaminoantrecenos [6,7] e as polinaftoquinonas [8,9] Resumo: Os poliaromáticos são um grupo de polímeros condutores composto por poliaminonaftalenos, poliaminoantracenos, poliaminonaftóis e polinaftoquinonas com a presença de dois ou três anéis aromáticos. Neste trabalho, filmes de poliaminoantraceno (PAA) e 1,5 polidiaminonaftaleno (1,5-PDAN) foram obtidos por eletropolimerização sobre eletrodos de platina, utilizando uma célula de três eletrodos e um único compartimento.…”

A Direct Electrochemical Biosensing Platform Constructed by Incorporating Carbon Nanotubes and Gold Nanoparticles onto Redox Poly(thionine) Film

“…1,2 It would be preferable to immobilize the electron-transfer mediators on the electrode surfaces so as to prepare direct or reagentless electrochemical sensors, mostly known as the third-generation enzyme biosensors. 3,5 Successful mediated biosensors have been fabricated with enzymes either chemically modified with the electron relays 6 or tethered to the mediating redox polymers premodified on the electrodes. 3,[7][8][9][10] However, some redox mediators in use may still suffer from low electron transfer efficiency or the inherent drawback of part solubility in the bulk solution leading to a gradual leaking of mediators during continuous sample analysis.…”

Plumbagin: a natural product for smart materials?

“…9,10 Electrochemical oxidation of the phenol should result in the production of a radical cation whose head-to-tail coupling-in line with conventional phenol based electropolymerisation-should lead to the deposition of a thin film directly at the electrode surface. 9,10 It would be hoped that the quinone component of the compound would be retained and remain accessible to electrochemical cycling and that upon the imposition of a reducing potential the hydroxyl form should be generated which-in the presence of oxygen-should result in the production of ROS (superoxide anion radical and ultimately peroxide) (Scheme 1). 3 The redox cycling capability of plumbagin and its ability to form an electropolymerised film capable of generating ROS is considered.…”

“…Poly-plumbagin films have been used in a number of biosensing applications 9 as an entrapment matrix. While a number of oxidation products can arise, it was anticipated that in this instance, electro-oxidation would lead to a predominantly non-conducting polyphenylene oxide film type formation consistent with conventional phenolic electro-oxidation.…”