Dispositivos Biosensores: desde el diseño a la aplicación real

3 páginas, 2 figuras.-- Curso impartido en el XXVII Congreso Nacional de la Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales (SMCTSM), Septiembre-2007, Oaxaca (Mexico).The Course will start with a basic introduction to biosensors, and will follow with a deep overview of the different physical transducer, with special emphasis in photonics and nanotechnology transducers. During the course, the design, fabrication, characterization, and testing of biosensor devices will be reviewed. In addition, the biofunctionalization techniques for biological receptor inclusion will be studied as well. Further integration of biosensors, microfluidics, and electronic functions on a single sensing circuit could lead to a complete ‘‘lab-on-achip’’ technological solution which could be used for performing in situ analysis. The way of the integration in ‘‘lab-on-a-chip’’ Microsystems will be also reviewed.Peer reviewe

Optimization Study of Bimodal Waveguide Interferometric Biosensors

Clinical diagnosis of diseases dependant on genetics of patients is still limited due to the lack of quick, precise, cheap and reliable technological tools. Such diagnostic tools would allow the design of personalized treatments for each patient according to its genetic profile. Photonic biosensors based on evanescent wave detection can afford such diagnostic tools. Using the evanescent wave detection principle, a new bimodal interferometer sensor has been proposed[1]. This device is comprised of a single mode rib waveguide which abruptly increases its core thickness to guide two transversal modes (TX00 and TX10) propagating until the output of the chip. A sensing area is defined in the bimodal part of the waveguide and, as the fundamental and first order modes have different intensity distribution at the core-cladding interface, the interface pattern is a function of the refractive index in the sensing area. A complete study is made starting from the previous device in order to improve its characteristics. The model used for simulations consisted of a variable thickness core layer (260-380 nm) of Si3N4 with n = 2.0 over a 2 µm SiO2 cladding layer with n = 1.46 and water (n=1.33) in the sensing area over the waveguide core using Film Mode Matching (FMM) Method in Photon Design 5.4[2]

Breakthroughs in photonics 2012: 2012 breakthroughs in lab-on-a-chip and optical biosensors

Open Access.-- Invited Paper.We review the most important achievements published in 2012 in the field of lab-on-a-chip (LOC) and optical biosensors. We will specially focus on optical label-free biosensors and their implementation into lab-on-a-chip platforms, with an emphasis on manuscripts demonstrating bioanalytical applications. © 2009-2012 IEEE.Peer Reviewe

Biochemistry strategies for label-free optical sensor biofunctionalization : advances towards real applicability

Label-free biosensors, and especially those based on optical transducers like plasmonic or silicon photonic systems, have positioned themselves as potential alternatives for rapid and highly sensitive clinical diagnostics, on-site environmental monitoring, and for quality control in foods or other industrial applications, among others. However, most of the biosensor technology has not yet been transferred and implemented in commercial products. Among the several causes behind that, a major challenge is the lack of standardized protocols for sensor biofunctionalization. In this review, we summarize the most common methodologies for sensor surface chemical modification and bioreceptor immobilization, discussing their advantages and limitations in terms of analytical sensitivity and selectivity, reproducibility, and versatility. Special focus is placed on the suggestions of innovative strategies towards antifouling and biomimetic functional coatings to boost the applicability and reliability of optical biosensors in clinics and biomedicine. Finally, a brief overview of research directions in the area of device integration, automation, and multiplexing will give a glimpse of the future perspectives for label-free optical biosensors

Matrix analysis of discontinuities in nonreciprocal waveguides: analytical description for magnetooptical slab waveguides

10 páginas, 9 figuras.A new analytical formalism to study the effect of discontinuities in a nonreciprocal waveguide has been developed. The analysis is based on 1) the general orthogonality relation obtained from the reciprocity theorem, 2) the modal expansion of the transverse electromagnetic fields within the waveguide, and 3) the continuity of the tangential components of such electromagnetic fields at both sides of the discontinuity. The formalism is presented in a matrix form, which allows the treatment of several discontinuities as a simple summation and product of coupling and propagation matrices. The matrix formalism is developed for magnetooptic waveguides in the three different orientations of the magnetization, and, within this context, two practical applications of magnetooptic isolators are studied.Peer reviewe

Current Trends in SPR Biosensing of SARS-CoV-2 Entry Inhibitors

The emerging risk of viral diseases has triggered the search for preventive and therapeutic agents. Since the beginning of the COVID-19 pandemic, greater efforts have been devoted to investigating virus entry mechanisms into host cells. The feasibility of plasmonic sensing technologies for screening interactions of small molecules in real time, while providing the pharmacokinetic drug profiling of potential antiviral compounds, offers an advantageous approach over other biophysical methods. This review summarizes recent advancements in the drug discovery process of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) inhibitors using Surface Plasmon Resonance (SPR) biosensors. A variety of SPR assay formats are discussed according to the binding kinetics and drug efficacies of both natural products and repurposed drugs. Special attention has been given to the targeting of antiviral agents that block the receptor binding domain of the spike protein (RBD-S) and the main protease (3CLpro) of SARS-CoV-2. The functionality of plasmonic biosensors for high-throughput screening of entry virus inhibitors was also reviewed taking into account experimental parameters (binding affinities, selectivity, stability), potential limitations and future applications.S

Plasmonic Biosensors for Single-Molecule Biomedical Analysis

Review[EN] The rapid spread of epidemic diseases (i.e., coronavirus disease 2019 (COVID-19)) has contributed to focus global attention on the diagnosis of medical conditions by ultrasensitive detection methods. To overcome this challenge, increasing efforts have been driven towards the development of single-molecule analytical platforms. In this context, recent progress in plasmonic biosensing has enabled the design of novel detection strategies capable of targeting individual molecules while evaluating their binding affinity and biological interactions. This review compiles the latest advances in plasmonic technologies for monitoring clinically relevant biomarkers at the single-molecule level. Functional applications are discussed according to plasmonic sensing modes based on either nanoapertures or nanoparticle approaches. A special focus was devoted to new analytical developments involving a wide variety of analytes (e.g., proteins, living cells, nucleic acids and viruses). The utility of plasmonic-based single-molecule analysis for personalized medicine, considering technological limitations and future prospects, is also overviewedS

Nanotecnología : la fuerza de lo muy pequeño (y su papel en la lucha contra la COVID-19)

Conferència realitzada el Dissabte, 6 de Febrer de 2021La Nanotecnología ha invadido nuestra vida y ya la estamos usando a diario, aunque muchos desconozcan cómo funciona el mundo nanotecnológico. En esta charla descubriremos que es y cómo funciona la Nanotecnología y examinaremos sus muchas aplicaciones presentes y futuras. Hablaremos de la Nanomedicina, la Nanotecnología dedicada al cuidado de la salud, y como sus avances nos están ayudando en la lucha contra la pandemia COVID-19 y como nos ayudará a estar preparados para futuras crisis sanitarias

Interferómetro y sensor basados en una guía de onda óptica bimodal y procedimiento de detección

Peer reviewedConsejo Superior de Investigaciones CientíficasT3 Traducción de patente europe

Decrease of the resonance bandwidth of micromechanical oscillators by phase control of the driving force

A method for controlling the amplitude response of micromechanical oscillators is presented. The micromechanical oscillator is driven by two forces acting both in phase, a fixed sinusoidal force and a feedback force whose amplitude depends on the phase shift. This dependence exhibits a pronounced maximum when the phase shift is 90°, i.e., at the resonant frequency. Experiments performed with a microcantilever prove that this class of active control decreases the bandwidth of the amplitude response about two orders of magnitude. The noise of the microcantilever, mainly of a thermal nature, is not increased at resonance, and it is moderately increased at both sides of the amplitude peak. Moreover, the noise can be tuned by adjusting the ratio between the two driving forces.Peer reviewe