Abstract: A microfluidic system includes a flexible substrate having a skin-facing surface and a back-facing surface; a microfluidic network at least partially embedded in or supported by the flexible substrate; a sensor fluidically connected to the microfluidic network, wherein the microfluidic network is configured to transport a biofluid from a skin surface to the sensor; and a capping layer, having a capping layer skin-facing surface and a back-facing surface, wherein the back-facing surface of the capping layer is attached to the skin-facing surface of the substrate. The flexible substrate is at least partially formed of a thermoplastic elastomer or a polymer configured to provide a high barrier to vapor or liquid water transmission.

Abstract: The invention provides a versatile sensing platform for sensing and analysis of biofluids, particularly well-suited for sensing and analysis of sweat. Systems of the invention allows for sensitive and selective detection of a range of analytes in sweat including metabolites, electrolytes and biomarkers. Systems of the invention provide a noninvasive and accurate means for quantitative characterization of important sweat characteristics including sweat volume, sweat loss and sweat rate. Systems of the invention are compatible with materials and device geometries for important class of conformal tissue mounted electronic devices, including epidermal electronic devices.

Abstract: Provided are conformable devices to measure subdermal fluid flow and related methods. A soft, stretchable and flexible substrate supports a thermal actuator and various specially positioned temperature sensors. A microprocessor in electronic communication with sensors calculates subdermal fluid flow from the measured upstream and downstream temperatures, as well as various application-dependent parameters. Devices and methods provided herein are particularly useful for measuring cerebral spinal fluid in a ventricular shunt placed for treatment of hydrocephalus.

Abstract: Provided are conformable devices to measure subdermal fluid flow and related methods. A soft, stretchable and flexible substrate supports a thermal actuator and various specially positioned temperature sensors. A microprocessor in electronic communication with sensors calculates subdermal fluid flow from the measured upstream and downstream temperatures, as well as various application-dependent parameters. Devices and methods provided herein are particularly useful for measuring cerebral spinal fluid in a ventricular shunt placed for treatment of hydrocephalus.

Abstract: Provided are conformable devices to measure subdermal fluid flow and related methods. A soft, stretchable and flexible substrate supports a thermal actuator and various specially positioned temperature sensors. A microprocessor in electronic communication with sensors calculates subdermal fluid flow from the measured upstream and downstream temperatures, as well as various application-dependent parameters. Devices and methods provided herein are particularly useful for measuring cerebral spinal fluid in a ventricular shunt placed for treatment of hydrocephalus.

Abstract: Provided are conformable devices to measure subdermal fluid flow and related methods. A soft, stretchable and flexible substrate supports a thermal actuator and various specially positioned temperature sensors. A microprocessor in electronic communication with sensors calculates subdermal fluid flow from the measured upstream and downstream temperatures, as well as various application-dependent parameters. Devices and methods provided herein are particularly useful for measuring cerebral spinal fluid in a ventricular shunt placed for treatment of hydrocephalus.

Abstract: The invention provides a versatile sensing platform for sensing and analysis of biofluids, particularly well-suited for sensing and analysis of sweat. Systems of the invention allows for sensitive and selective detection of a range of analytes in sweat including metabolites, electrolytes and biomarkers. Systems of the invention provide a noninvasive and accurate means for quantitative characterization of important sweat characteristics including sweat volume, sweat loss and sweat rate. Systems of the invention are compatible with materials and device geometries for important class of conformal tissue mounted electronic devices, including epidermal electronic devices.

Abstract: Provided are microfluidic systems for monitoring a biofluid property and related methods. Specially configured microfluidic networks and associated structural support and functional elements, including flexible substrates, capping layers, and fluidic conduits and controllers, provide reliable biofluid collection. Optical components and indicators provide a reliable and readily observable readout, including of any of a number of biofluid properties, including directly from biofluid collected in the microfluidic network.

Abstract: Provided are conformable devices to measure subdermal fluid flow and related methods. A soft, stretchable and flexible substrate supports a thermal actuator and various specially positioned temperature sensors. A microprocessor in electronic communication with sensors calculates subdermal fluid flow from the measured upstream and downstream temperatures, as well as various application-dependent parameters. Devices and methods provided herein are particularly useful for measuring cerebral spinal fluid in a ventricular shunt placed for treatment of hydrocephalus.

Abstract: A microfluidic system includes a flexible substrate having a skin-facing surface and a back-facing surface; a microfluidic network at least partially embedded in or supported by the flexible substrate; a sensor fluidically connected to the microfluidic network, wherein the microfluidic network is configured to transport a biofluid from a skin surface to the sensor; and a capping layer, having a capping layer skin-facing surface and a back-facing surface, wherein the back-facing surface of the capping layer is attached to the skin-facing surface of the substrate. The flexible substrate is at least partially formed of a thermoplastic elastomer or a polymer configured to provide a high barrier to vapor or liquid water transmission.

Abstract: Provided are microfluidic systems for monitoring a biofluid property and related methods. Specially configured microfluidic networks and associated structural support and functional elements, including flexible substrates, capping layers, and fluidic conduits and controllers, provide reliable biofluid collection. Optical components and indicators provide a reliable and readily observable readout, including of any of a number of biofluid properties, including directly from biofluid collected in the microfluidic network.

Abstract: Provided herein are flexible, microfluidic epidermal systems and methods useful in the analysis of biofluids for biomarkers corresponding to a variety of conditions and methods of use. The provided systems configured to create conformal contact with the skin to allow for medical testing or screening, either in situ or later external laboratory testing. The described devices and methods may be used for cystic fibrosis screening, glucose monitoring, drug and/or alcohol testing, creatinine monitoring, urea monitoring, pH measurement and dialysis treatment efficacy testing.