Using an image-based method for label-free detection of biochemical binding density distribution on the surface of a photonic crystal biosensor mbedded within standard format multiwell microplates, a new method for automatic referencing of assay errors due to variability in the bulk efractive index of the analyte test sample is demonstrated. The new method involves application of the immobilize...

Real-time measurement of specific biomolecular interactions is critical to many areas of biological research. A number of label-free techniques for directly monitoring biomolecular binding have been developed, but it is still challenging to measure the binding kinetics of very small molecules, to detect low concentrations of analyte molecules, or to detect low affinity interactions. In this stu...

designing a power splitter with five ports has been shown in this article. in order to prevent the direct coupling between waveguides, a t-shaped structure with an appropriate distance has been used. the coupling between the parallel photonic crystal waveguides is based on multimode interference, while selecting the output efficiency is performed by setting the refractive coefficients and radiu...

Biosensor technologies that have been primarily used in the past for characterizing biomolecular interactions are now being used to develop new approaches for performing cell-based assays. Biosensors monitor cell attachment to a transducer surface, and thus provide information that is fundamentally different from that provided by microscopy, as the sensor is capable of monitoring temporal evolu...

in the present paper, resonant frequencies and modes of a three-atom photonic molecule and a photonic crystal placed within a cavity are numerically calculated. first, governing formulation in transverse electric field mode (te) is obtained using maxwell equations. then, an algorithm based on a finite difference scheme and matrix algebra is presented. the algorithm is then implemented in a comp...

Plasmonic nanoparticles are commonly used as optical transducers in sensing applications. The optical signals resulting from the interaction of analytes and plamsonic nanoparticles are influenced by surrounding physical structures where the nanoparticles are located. This paper proposes inverse opal photonic crystal hydrogel as 3D structure to improve Raman signals from plasmonic staining. By h...

A form of microscopy that utilizes a photonic crystal biosensor surface as a substrate for cell attachment enables label-free, quantitative, submicron resolution, time-resolved imaging of cell-surface interactions without cytotoxic staining agents or temporally-unstable fluorophores. Other forms of microscopy do not provide this direct measurement of live cell-surface attachment localization an...

The simultaneous quantitation of multiple steroid hormones in real time is of great importance in medical diagnosis. In this study, a portable hormone biosensor based on duplex molecular recognition coupled with a signal-amplified substrate was successfully developed for the simultaneous visualization and quantitation of multiple steroid hormones. Aptamer-functionalized upconversion nanoparticl...

A simple optical method using hollow-core photonic crystal fiber for protein detection has been described. In this study, estrogen receptor (ER) from a MCF-7 breast carcinoma cell lysates immobilized inside a hollow-core photonic crystal fiber was detected using anti-ER primary antibody with either Alexa Fluor 488 (green fluorescent dye) or 555 (red Fluorescent dye) labeled Goat anti-rabbit IgG...