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Abstract(s)
Ara h 1 é uma proteína que provoca reações alérgicas em indivíduos hipersensíveis e que pertence a um leque de proteínas alérgicas do amendoim. As alergias alimentares têm vindo a ser alvo de estudo, pelo facto de estas terem vindo a aumentar, inclusive a alergia ao amendoim. Os diagnósticos são realizados através de testes da picada, controlados em ambientes que sejam capazes de responder a uma eventual reação aguda. O conhecimento precoce da hipersensibilidade à Ara h 1 torna-se um ponto crucial para melhorias na qualidade de vida de qualquer pessoa, para isso é essencial o conhecimento da existência, mesmo em condições vestigiais, desta em produtos alimentares. Neste contexto, na UE encontra-se em vigor legislação que exige que informação acerca de uma lista prioritária de ingredientes alérgicos seja indicada no rótulo de alimentos pré-embalados, isolados e preparados. No entanto, esta legislação só se foca na indicação de ingredientes e não na quantidade dos mesmos no alimento. Isto tem levado à adoção de indicações preventivas como “pode conter vestígios de…” por parte da indústria. Estas indicações restringem desnecessariamente a dieta de consumidores alérgicos, podendo levar a atitudes de risco que conduzem à exposição aos alergénios. Assim, tanto para consumidores alérgicos como para a indústria alimentar e as entidades reguladoras, informações acerca da presença e a quantidade de alergénios nos alimentos levará a condições mais seguras e lucrativas. Isto exige o desenvolvimento de métodos para a deteção de quantidades vestigiais de alergénios em alimentos. Assim, neste trabalho foi desenvolvido um sensor eletroquímico seletivo para Ara h 1. Devido ao seu baixo custo, facilidade de preparação, portabilidade e sensibilidade, os sensores eletroquímicos apresentam-se como uma boa solução para a deteção rápida de alergénios. Recentemente a combinação da tecnologia de polímeros molecularmente impressos (MIPs), com as técnicas eletroquímicas tem permitido a preparação de sensores de alta seletividade. Neste trabalho foram utilizados elétrodos (screen-printed) de carbono descartáveis para a preparação de um sensor molecularmente impresso seletivo para a Ara h 1. A preparação do MIP foi realizada por eletropolimerização, recorrendo à voltametria cíclica (CV), diretamente na superfície do elétrodo de trabalho, um monómero funcional, o pirrol, e a Ara h 1. Foram otimizadas várias condições de polimerização, tais como, concentração de pirrol, concentração de Ara h 1, número de ciclos de polimerização, condições de extração e realizou-se uma caracterização do sensor por voltametria cíclica. O sensor mostrou uma resposta linear entre as concentrações de Ara h 1 entre 2 e 10 ng/mL.
Ara h 1 is a protein that causes allergic reactions in hypersensitive individuals and belongs to a range of allergic proteins from peanut. Food allergies have been the subject of study, because they have been increasing, including allergy to peanut. The diagnoses are carried out by sting testing, in controlled environments that can respond to an eventual acute reaction. The early knowledge of Ara h 1 hypersensitivity becomes a crucial point to improve the quality of life of any person. Therefore, it is essential to know the presence, even in trace amounts, of this allergen in food products. In this context, in EU legislation is in place that requires information on a priority list of allergic ingredients to be indicated on the label of pre-packaged, isolated and prepared foods. However, this legislation only focuses on the indication of ingredients and not on the quantity of these ingredients in the food. This has led to the adoption of preventive indications such as “may contain traces of…” by the industry. These indications unnecessarily restrict the diet of allergic consumers, which may lead to risky attitudes leading to exposure to allergens. Thus, for both allergic consumers and for the food industry and regulatory authorities, information on the presence and amount of allergens in food will lead to safer and more profitable conditions. This requires the development of methods that can detect trace amounts of allergens in food products. Thus, in this work a selective electrochemical sensor was developed for the analysis of Ara h 1. Due to their low cost, ease of preparation, portability and sensitivity, electrochemical sensors are good solution for the rapid detection of allergens. Recently, the combination of molecularly- imprinted polymers (MIPs) with electrochemical techniques has allowed the development of highly selective sensors. In this work, disposable screen-printed carbon electrodes were used to prepare a molecularly imprinted sensor for Ara h 1. The preparation of the MIP was carried out by electropolymerization, using cyclic voltammetry (CV), directly on the surface of the working electrode, using as a solution containing pyrrole and Ara h 1. Various polymerization conditions were optimized, such as the concentration of pyrrole and Ara h 1, the number of polymerization cycles and the extraction conditions. The sensor was characterized by cyclic voltammetry and showed a linear response between 2 and 10 ng/mL
Ara h 1 is a protein that causes allergic reactions in hypersensitive individuals and belongs to a range of allergic proteins from peanut. Food allergies have been the subject of study, because they have been increasing, including allergy to peanut. The diagnoses are carried out by sting testing, in controlled environments that can respond to an eventual acute reaction. The early knowledge of Ara h 1 hypersensitivity becomes a crucial point to improve the quality of life of any person. Therefore, it is essential to know the presence, even in trace amounts, of this allergen in food products. In this context, in EU legislation is in place that requires information on a priority list of allergic ingredients to be indicated on the label of pre-packaged, isolated and prepared foods. However, this legislation only focuses on the indication of ingredients and not on the quantity of these ingredients in the food. This has led to the adoption of preventive indications such as “may contain traces of…” by the industry. These indications unnecessarily restrict the diet of allergic consumers, which may lead to risky attitudes leading to exposure to allergens. Thus, for both allergic consumers and for the food industry and regulatory authorities, information on the presence and amount of allergens in food will lead to safer and more profitable conditions. This requires the development of methods that can detect trace amounts of allergens in food products. Thus, in this work a selective electrochemical sensor was developed for the analysis of Ara h 1. Due to their low cost, ease of preparation, portability and sensitivity, electrochemical sensors are good solution for the rapid detection of allergens. Recently, the combination of molecularly- imprinted polymers (MIPs) with electrochemical techniques has allowed the development of highly selective sensors. In this work, disposable screen-printed carbon electrodes were used to prepare a molecularly imprinted sensor for Ara h 1. The preparation of the MIP was carried out by electropolymerization, using cyclic voltammetry (CV), directly on the surface of the working electrode, using as a solution containing pyrrole and Ara h 1. Various polymerization conditions were optimized, such as the concentration of pyrrole and Ara h 1, the number of polymerization cycles and the extraction conditions. The sensor was characterized by cyclic voltammetry and showed a linear response between 2 and 10 ng/mL
Description
Keywords
Alergias Alimentares Alergénio Sensor Eletroquímico Ara h 1 Polímero Molecularmente Impresso Food Allergies Allergen Electrochemical Sensor Molecularly Printed Polymer