Abstract: Apparatus and methods for modulating flow rates in microfluidic devices are provided. The methods involve modulating downstream pressure in the device to change the flow rate of materials in an upstream region of the device. Such methods include electrokinetic injection or withdrawal of materials through a side channel and the use of an absorbent material to induce wicking in the channel system. The apparatus provided includes a prefabricated wick in the device to provide for flow rate control. Additional methods for determining velocity of a particle and cell incubation time are also provided.

Abstract: Intracellular binding reactions, and particularly DNA/DNA binding protein reactions are detected in situ, using intracellular fluorescence polarization detection. The methods comprise providing a biological cell having at least a first component of a binding reaction disposed therein. The cell is contacted with a second component of the binding reaction whereby the second component is internalized within the biological cell. At least one of the first and second components has a fluorescent label. The amount of binding between the first and second components within the cell is determined by measuring a level of polarized and/or depolarized fluorescence emitted from within the biological cell.

Abstract: Intracellular binding reactions, and particularly DNA/DNA binding protein reactions are detected in situ, using intracellular fluorescence polarization detection. The methods comprise providing a biological cell having at least a first component of a binding reaction disposed therein. The cell is contacted with a second component of the binding reaction whereby the second component is internalized within the biological cell. At least one of the first and second components has a fluorescent label. The amount of binding between the first and second components within the cell is determined by measuring a level of polarized and/or depolarized fluorescence emitted from within the biological cell.

Abstract: Methods, devices and systems for increasing the throughput of screening assays by pooling multiple target systems, which allow a library of different materials, e.g., test compounds, to be screened against the pooled targets to determine whether any of the materials affect one or more of the target systems. In preferred aspects, functioning of individual target systems is identified by differences in physical, chemical and/or optical properties particular to the target system in a target pool.

Abstract: Copper chelates serve as cytotoxic agents in conjunction with a surface membrane protein receptor internalizing agent, particularly TNF, which has independent cytotoxic activity, for use against target cells. By employing concentrations of the two agents, where the agents have substantially reduced adverse side effects, the combination is shown to have effective cytotoxic activity.