19 research outputs found
Signal Enhancement Strategies in Classical Electrochemiluminescence Techniques for Modern Biosensing
With the ascent of IT, and since Ashton has invented the term Internet of Things (IoT) in 1999, this future idea of connected machines that can do tasks and perform decision-control cycles without human input has become more and more attractive and is today an established future scenario. Obviously, in an IoT, “sensors for everything” are one crucial corner stone of its existence and Analytical chemistry can and must deliver them. While many challenges towards a functioning IoT remain, we are on the verge of its beginning. This can be also seen with “Analytics 4.0” in research and on the market, tending to more IT-connected, portable, easier-controllable and integrated solutions. The entrance of mobility in the health sector or Point-of-Care (POC) diagnostics trends are alike influencing biosensing. Whether in mobile solutions or lab- and clinical environments, versatile, powerful and easy-to-adapt detection strategies like Electrochemiluminescence (ECL) are an attractive option.
The ECL molecules [Ru(bpy)3]2+ and luminol represent the most prominent and most abundantly investigated luminophores for ECL since Bard’s accomplishment to make ECL a well-known technique. Because both are also two of the most efficient ECL emitters that can be well-handled in bioanalysis, and are available on the market, they are still today frequently used in research and also commercial applications. To cope with current benchmarks of sensitive detection, however a combination with a certain signal enhancement strategy is recommended. Several different routes can here be employed and one option is dendrimers. PAMAM dendrimers can function as ECL coreactant in [Ru(bpy)3]2+-ECL via their amino groups and at the same time expose primary amino groups as possible bioconjugation elements. Exploring this multi-functionality of the dendrimers was investigated here. This was done on a model system employing PAMAM dendrimers with [Ru(bpy)3]2+-ECL together with biotin/streptavidin as biorecognition element and analyte, respectively. The dendrimer’s bi-functionality was successfully proven and a joint-role of a biorecognition element and a possible reporter function suggests an optimum application in homogeneous assays. A different toolset for ECL signal enhancement is offered by liposomes. Numerous signaling molecules can be encapsulated inside the inner cavity of these synthetic vesicles, while they provide protection from the environment and connection-functionality to probes via lipids and surface groups on the outside. That application was here explored, together with a newly synthesized luminol derivative obtained by a simple synthesis route from commercial starting materials and exhibiting a four times increased ECL efficiency versus standard luminol. That was necessary as a liposome enhancement was denied for the standard luminol through its poor aqueous solubility. The new m-carboxy luminol considerably improved this feature which allowed its own encapsulation in liposomes. The superior signal generation with this dual system was proven in a model sandwich hybridization assay which yielded a 150-times better detection performance than the equal fluorescence-based assay while being almost zero affected through matrices like serum, soil or river water. As such the good performance of luminol ECL together with liposomes for highly sensitive detection applications was demonstrated. A further necessary element with liposomal amplification, are surfactants to set free the signaling molecules. However, this case depicts only one example of a multitude of applications of surfactants in bioassays and biochemical methods. Hence, surfactants are commonly present solution constituents which also have to be considered in general with ECL because they can influence the ECL signals positively or negatively. This was further investigated for luminol ECL by exploring the effect of 13 different surfactants on the luminol ECL efficiency on four different electrode materials. A deeper understanding of the distinct effects was obtained by looking into ECL emission behavior, electrochemical effects, the surfaces and Chemiluminescence effects. After all, the revelation of a complicated mechanism that involves many contributing factors and as such directs signal quenching or enhancement is an important finding for assay design. In this way, the selection of a suitable surfactant is possible to exploit maximum reachable signal efficiencies.
A combination of signal enhancement tools like a better ECL molecule derivative, dendrimers, liposomes or surfactants has proven to boost the ECL performance considerably. A further means of signal enhancement is offered via miniaturization, which also makes the detection method better suited towards common application as liquid handling and easier automation are on hand. This can be used for single ECL assays or combinations of different ECL reagents in one system for multi-detection. Different strategies for the miniaturization of an ECL readout-capable system were investigated, taking requirements for [Ru(bpy)3]2+ and luminol as ECL reporters into account. This includes materials, electrochemical demands and simple design. Here, ITO electrodes – while advantageous for luminol ECL could not convince with their performance in [Ru(bpy)3]2+-ECL. Alternatively, laser scribed graphene electrodes have shown to be promising candidates for a future miniaturized system encompassing both, luminol and [Ru(bpy)3]2+ as ECL systems. Ultimately, the different signal amplifying strategies, investigated in this work that can be applied standalone or combined, offer a great toolset for state-of-the-art ECL detection applications in research and also for possible commercial applications
2023-2024 Boise State University Undergraduate Catalog
This catalog is primarily for and directed at students. However, it serves many audiences, such as high school counselors, academic advisors, and the public. In this catalog you will find an overview of Boise State University and information on admission, registration, grades, tuition and fees, financial aid, housing, student services, and other important policies and procedures. However, most of this catalog is devoted to describing the various programs and courses offered at Boise State
Anuário Científico – 2009 & 2010 Resumos de Artigos, Comunicações, Teses, Patentes, Livros e Monografias de Mestrado
O Conselho Técnico-Científico do Instituto Superior de Engenharia de Lisboa (ISEL), na senda da consolidação da divulgação do conhecimento e da ciência desenvolvidos pelo nosso corpo docente, propõe-se publicar mais uma edição do Anuário Científico, relativa à produção científica de 2009 e 2010.
A investigação, enquanto vertente estratégica do Instituto Superior de Engenharia de Lisboa (ISEL), tem concorrido para o seu reconhecimento nacional e internacional como instituição de referência e de qualidade na área do ensino das engenharias.
É também nesta vertente que o ISEL consubstancia a sua ligação à sociedade portuguesa e internacional através da transferência de tecnologia e de conhecimento, resultantes da sua atividade científica e pedagógica, contribuindo para o seu desenvolvimento e crescimento de forma sustentada.
São parte integrante do Anuário Científico todos os conteúdos com afiliação ISEL resultantes de resumos de artigos publicados em livros, revistas e atas de congressos que os docentes do ISEL apresentaram em fóruns e congressos nacionais e internacionais, bem como teses e patentes.
Desde 2002, ano da publicação da primeira edição, temos assistido a uma evolução crescente do número de publicações de conteúdos científicos, fruto do trabalho desenvolvido pelos docentes que se têm empenhado com afinco e perseverança.
Contudo, nestes dois anos (2009 e 2010) constatou-se um decréscimo no número de publicações, principalmente em 2010. Uma das causas poderá estar diretamente relacionada com a redução do financiamento ao ensino superior uma vez que limita toda a investigação no âmbito da atividade de I&D e da produção científica.
Na sequência da implementação do Processo de Bolonha em 2006, o ISEL promoveu a criação de cursos de Mestrado disponibilizando uma oferta educativa mais completa e diversificada aos seus alunos, mas também de outras instituições, dotando-os de competências inovadoras apropriadas ao mercado de trabalho que hoje se carateriza mais competitivo e dinâmico. Terminados os períodos escolar e de execução das monografias dos alunos, os resumos destas são igualmente parte integrante deste Anuário, no que concerne à conclusão dos Mestrados em 2009 e 2010.A fim de permitir uma maior acessibilidade à comunidade científica e à sociedade civil, o Anuário Científico será editado de ora avante em formato eletrónico.
Excecionalmente esta edição contempla publicações referentes a dois anos – 2009 e 2010
2020-2021 Boise State University Undergraduate Catalog
This catalog is primarily for and directed at students. However, it serves many audiences, such as high school counselors, academic advisors, and the public. In this catalog you will find an overview of Boise State University and information on admission, registration, grades, tuition and fees, financial aid, housing, student services, and other important policies and procedures. However, most of this catalog is devoted to describing the various programs and courses offered at Boise State
2021-2022 Boise State University Undergraduate Catalog
This catalog is primarily for and directed at students. However, it serves many audiences, such as high school counselors, academic advisors, and the public. In this catalog you will find an overview of Boise State University and information on admission, registration, grades, tuition and fees, financial aid, housing, student services, and other important policies and procedures. However, most of this catalog is devoted to describing the various programs and courses offered at Boise State
2022-2023 Boise State University Undergraduate Catalog
This catalog is primarily for and directed at students. However, it serves many audiences, such as high school counselors, academic advisors, and the public. In this catalog you will find an overview of Boise State University and information on admission, registration, grades, tuition and fees, financial aid, housing, student services, and other important policies and procedures. However, most of this catalog is devoted to describing the various programs and courses offered at Boise State
2019-2020 Boise State University Undergraduate Catalog
This catalog is primarily for and directed at students. However, it serves many audiences, such as high school counselors, academic advisors, and the public. In this catalog you will find an overview of Boise State University and information on admission, registration, grades, tuition and fees, financial aid, housing, student services, and other important policies and procedures. However, most of this catalog is devoted to describing the various programs and courses offered at Boise State