Showing papers by "Eric Stern published in 2009"

Nanoelectronic-enzyme linked immunosorbent assay system and method

Abstract: The present invention relates to a device and method for determining the presence of a specific compound in solution. The device includes a nanosensor having an electrically conducting pathway between at least a first and second contact. The device also includes a first receptor, suitable for binding a specific compound in the solution, attached to the nanosensor, and a second receptor also suitable for binding the specific compound while the specific compound is bound to the first receptor. The second receptor is attached to an enzyme added to the solution. When the solution having the second receptor is added to the device, and a second compound that is a substrate for the enzyme is subsequently added to the solution, a measured difference in an electrical property in the device before and after the application of the second compound is indicative of the presence of the specific compound in the solution.

Spatiotemporal control over molecular delivery and cellular encapsulation from electropolymerized micro- and nanopatterned surfaces.

Abstract: Bioactive, patterned micro- and nanoscale surfaces that can be spatially engineered for three-dimensional ligand presentation and sustained release of signaling molecules represent a critical advance for the development of next-generation diagnostic and therapeutic devices. Lithography is ideally suited to patterning such surfaces due to its precise, easily scalable, high-throughput nature; however, to date polymers patterned by these techniques have not demonstrated the capacity for sustained release of bioactive agents. We demonstrate here a class of lithographically-defined, electropolymerized polymers with monodisperse micro- and nanopatterned features capable of sustained release of bioactive drugs and proteins. We show that precise control can be achieved over the loading capacity and release rates of encapsulated agents and illustrate this aspect using a fabricated surface releasing a model antigen (ovalbumin) and a cytokine (interleukin-2) for induction of a specific immune response. We further demonstrate the ability of this technique to enable three-dimensional control over cellular encapsulation. The efficacy of the described approach is buttressed by its simplicity, versatility, and reproducibility, rendering it ideally suited for biomaterials engineering.

A biomimetic approach for the creation of two-dimensional microscale surface patterns: creation of isolated immunological synapses.

Abstract: Current efforts in surface functionalization have not produced a robust technique capable of creating specific two-dimensional microscale geometrical arrays composed of multiple proteins. Such a capability is desirable for engineering substrates in sensing and cell patterning applications where at least two different protein functionalities in a specific configuration are required. Here we introduce a new approach for the creation of arrays of microscale geometries. We demonstrate our approach with a biomimetic structure inspired by the immunological synapse, a cell-cell interfacial structure characterized by two concentric rings of proteins: an outer adhesion protein structure and an inner recognition ligand core. The power of the technique lies in its ability to pattern any protein in any defined geometry as well as to create arrays in parallel.