Analytical technologies based upon superparamagnetic beads, SPBs, offer a rapid, simple and inexpensive way of separating and purifying the target analyte prior to detection. The SPBs can perform the capture, purification and the signal transduction stages, producing a simple, fast, and sensitive label-free format. Particle aggregation in the presence of the analyte is a common example of such ...

Light that penetrates scattering media shows nonlinearities that mask the broad and shallow perturbations made by trace analytes on the background illuminant spectrum. Narrow-band spectroscopic decomposition and deconvolution of such weak bands is a formidable analytical task that pushes the fundamentally linear spectroscopic method beyond practical limits. Kromoscopy is a high-dimensional anal...

A model to quantitate the principal aspects of multivalent binding was developed. It describes the random distribution of an immobilized component (the ligand) taking into account local densities. The binding of a bivalent molecule (the analyte) to the ligand is described as occurring in two steps, the second of which is driven by the local concentration of neighboring ligands. The model was us...

This paper reports on the development of an open-closed configuration for continuous kinetic methods based on photochemical reactions; the configuration removes the need to use special flow cells for simultaneous irradiation and detection. The sample plug was recirculated through a circuit including the detector and a coil irradiated with an ultra-violet source. A multipeak recording per inject...

Diagnostic tests in resource-limited settings require technologies that are affordable and easy to use with minimal infrastructure. Colorimetric detection methods that produce results that are readable by eye, without reliance on specialized and expensive equipment, have great utility in these settings. We report a colorimetric method that integrates a paper-based immunoassay with a rapid, visi...

Optical techniques may potentially be used for noninvasive glucose sensing. We investigated the application of phase-sensitive optical low-coherence reflectometry (PS-OLCR) to the measurement of analyte concentrations. The dependence of the PS-OLCR signal on the concentration of various analytes, including aqueous solutions of glucose, calcium chloride, magnesium chloride, sodium chloride, pota...

In recent years, there has been a massive effort to develop molecular probes with optical modes of action. Probes generally produce detectable signals based on changes in fluorescence properties. Here, we demonstrate the potential of self-immolative molecular adaptors as a platform for Turn-On probes based on the FRET technique. The probe is equipped with identical fluorophore pairs or a fluoro...

A leading application of biomolecular interaction analysis technology is the characterization of antibodyantigen interactions. By measuring the association and dissociation rates of the interaction, antibodies with desired binding characteristics can be identified. A rapid association rate and a slow dissociation rate may be indicative of therapeutic efficacy. Affinity maturation programs exist...

Label-free technologies are mostly used for detection of biomolecular interactions between proteins or other macromolecules. Characterization of small molecule to protein binding has often been a challenge because label-free signal depends on molecular weight of the analyte and analyte-to-target molecular weight ratio. In this study we show that Nanopore Optical Interferometry (NPOI) can be use...

A biosensor is described as a compact analytical device, incorporating a biological or biologically derived sensing element, either closely connected to, or integrated within, a transducer system. The principle of detection is the specific binding of the analyte of interest to the complementary biorecognition element immobilized on a suitable support matrix. The specific interaction results in ...