Showing papers by "Xingyu Jiang published in 2004"

Compatibility of mammalian cells on surfaces of poly(dimethylsiloxane).

Abstract: This paper describes the influence of the composition of poly(dimethylsiloxane) (PDMS) on the attachment and growth of several different types of mammalian cells: primary human umbilical artery endothelial cells (HUAECs), transformed 3T3 fibroblasts (3T3s), transformed osteoblast-like MC3T3-E1 cells, and HeLa (transformed epithelial) cells. Cells grew on PDMS having different ratios of base to curing agent: 10:1 (normal PDMS, PDMSN), 10:3 (PDMSCA), and 10:0.5 (PDMSB). They were also grown on “extracted PDMS” (normal PDMS that has reduced quantities of low molecular-weight oligomers, PDMSN,EX) and normal PDMS that had been extracted and then oxidized (PDMSN,EX,OX); all surfaces were exposed to a solution of fibronectin prior to cell attachment. Generally, fibronectin-coated PDMS is a suitable substrate for culturing mammalian cells. Compatibility of cells on some surfaces, however, was dependent on the cell type: PDMSN,EX,OX caused cell detachment of 3T3 fibroblasts and MC3T3-E1 cells, and PDMSCA caused...

Fluidic arrays and method of using

Abstract: The present invention relates to fluidic systems and, in particular, fluidic arrays and methods for using them to promote interaction of materials. In one embodiment, the present invention is directed to a microfluidic system. The microfluidic system includes a first fluid path and a second fluid path segregated from the first fluid path by a first convection controller at a first contact region, wherein at least one of the first fluid path and the second fluid path has a cross-sectional dimension of less than about 1 millimeter. In another aspect, the present invention is directed to a method of promoting interaction. In another aspect, the invention relates to a device and method for performing titrations.

Palladium as a substrate for self-assembled monolayers used in biotechnology.

Abstract: This paper describes self-assembled monolayers (SAMs) on palladium that resist the nonspecific adsorption of proteins and the adhesion of mammalian cells. These SAMs form when thin films of palladi...

Potentiometric titrations in a poly(dimethylsiloxane)-based microfluidic device.

Abstract: This paper describes a microfluidic device, fabricated in poly(dimethylsiloxane), that is used for potentiometric titrations. This system generates step gradients of redox potentials in a series of microchannels. These potentials are probed by microelectrodes that are integrated into the chip; the measured potentials were used to produce a titration curve from which the end point of a reaction was measured.

Alteration of surface affinities

Abstract: The present invention provides a series of methods, compositions, and articles for altering a property of a surface (for example, the cytophilicity and/or the hydrophilicity), by exposing at least a portion of the surface to a non-chemical, force-creating field and/or force, such as an electric field. The field/force may be created by any suitable technique. For instance, the field can be created by applying a voltage across the surface, by electrical induction, etc. In certain embodiments, the surface includes molecules attached thereto that can be detached when exposed to non-chemical, force-creating fields and/or forces, thereby altering the chemical composition of at least a portion of the surface. In one set of embodiments, the molecules attached to the surface may include molecules forming a self-assembled monolayer on the surface. In some embodiments, the molecules attached to the surface may include thiol moieties (e.g., as in an alkanethiol), by which the molecule can become attached to the surface. In certain cases, the molecules may be terminated at the unattached end with one or more hydrophilic groups, for example, unmodified ethylene glycol moieties. In some cases, the molecules attached to the surface may include one or more moieties that can bind to various entities such as proteins, peptides, nucleic acids, drugs, cells, etc. In certain embodiments, the techniques are used to enable novel assays for cell motility and/or spreading and screening tests for determining drugs and/or treatments effective in increasing or decreasing cell shape changes and/or motility on surfaces.