Abstract: This disclosure describes microfluidic devices that include one or more magnets, each magnet being operable to emit a magnetic field; and a magnetizable layer adjacent to the one or more magnets, in which the magnetizable layer is configured to induce a gradient in the magnetic field of at least one of the magnets. For example, the gradient can be at least 103 T/m at a position that is at least 20 ?m away from a surface of the magnetizable layer. The magnetizable layer includes a first high magnetic permeability material and a low magnetic permeability material arranged adjacent to the high magnetic permeability material. The devices also include a microfluidic channel arranged on a surface of the magnetizable layer, wherein a central longitudinal axis of the microfluidic channel is arranged at an angle to or laterally offset from an interface between the high magnetic permeability material and the low magnetic permeability material.

Abstract: In some embodiments, the present invention generally relates to the separation of blood within a device to form plasma or serum. In some embodiments, the present invention generally relates to the removal of fluids, such as blood, contained within a device. In one aspect, the present invention is generally directed to systems and methods for receiving blood from a subject and processing the blood to form plasma or serum. For example, a device may be applied to the skin of a subject to receive blood from the subject and pass the blood through a separation membrane, which separates the blood into plasma and a portion concentrated in blood cells. As another example, blood or plasma may be allowed to clot within the device and serum (the unclotted portion of the blood) may be withdrawn from the device. The device may contain, in some cases, a vacuum source such as a pre-packaged vacuum to facilitate receiving of blood and/or passage of the blood through the separation membrane to produce plasma or serum.

Abstract: The present invention generally relates to devices and techniques associated with diagnostics, therapies, and other applications, including skin-associated applications, for example, devices for delivering and/or withdrawing fluid from subjects, e.g., through the skin. In some embodiments, the device includes a system for accessing an extractable medium from and/or through the skin of the subject at an access site, and a pressure regulator supported by a support structure, able to create a pressure differential across the skin at at least a portion of the access site. The device may also include, in some cases, a sensor supported by the support structure for determining at least one condition of the extractable medium from the subject, and optionally a signal generator supported by the support structure for generating a signal relating to the condition of the medium determined by the sensor.

Abstract: Microfluidic cuvettes and a network of multiplexed channels including such cuvettes. The channels operationally share a main output channel defining an output of the network. A microfluidic channel includes an inlet, a cuvette, and an outlet that is coupled into the main output channel. The network is configured to provide a difference in resistances, to the fluid, by the main output channel and by an individual outlet is sufficient to prevent cross-contamination of different cuvettes, thereby operably isolating individual channels from one another. An individual cuvette is adapted to substantially prevent the formation of air-bubbles as part of the fluid flow through the cuvette and, therefore, to be fully filled and fully emptied. A system and method for photometric measurements of multiple fluid samples employing such network of channels.

Abstract: In some embodiments, the present invention generally relates to the separation of blood within a device to form plasma or serum. In some embodiments, the present invention generally relates to the removal of fluids, such as blood, contained within a device. For example, a device may be applied to the skin of a subject to receive blood from the subject and pass the blood through a separation membrane, which separates the blood into plasma and a portion concentrated in blood cells. As another example, blood or plasma may be allowed to clot within the device and serum (the unclotted portion of the blood) may be withdrawn from the device. The device may contain, in some cases, a vacuum source such as a pre-packaged vacuum to facilitate receiving of blood and/or passage of the blood through the separation membrane to produce plasma or serum.

Abstract: The present invention generally relates to devices and techniques associated with diagnostics, therapies, and other applications, including skin-associated applications, for example, devices for delivering and/or withdrawing fluid from subjects, e.g., through the skin. In some embodiments, the device includes a system for accessing an extractable medium from and/or through the skin of the subject at an access site, and a pressure regulator supported by a support structure, able to create a pressure differential across the skin at least a portion of the access site. The device may also include, in some cases, a sensor supported by the support structure for determining at least one condition of the extractable medium from the subject, and optionally a signal generator supported by the support structure for generating a signal relating to the condition of the medium determined by the sensor.

Abstract: Systems and methods for delivering and/or receiving a substance or substances, such as blood, from subjects. In one embodiment, devices and methods for receiving blood from a subject employ devices including a substance transfer component (such as one or more microneedles), and a storage chamber having an internal pressure less than atmospheric pressure prior to receiving blood. In certain embodiments, substances may be received from and/or delivered to the subject with relatively little pain. The pain may be assessed, for example, using pain scales such as the WONG BAKER FACES Pain Scale. The device may be self-contained, applied to the skin, and activated to receive blood from the subject. The device, or a portion thereof, may be processed to determine the blood and/or an analyte within the blood using sensors or agents in the device or an external apparatus.

Abstract: The present invention generally relates to devices and techniques associated with diagnostics, therapies, and other applications, including skin-associated applications, for example, devices for delivering and/or withdrawing fluid from subjects, e.g., through the skin. In some embodiments, the device includes a system for accessing an extractable medium from and/or through the skin of the subject at an access site, and a pressure regulator supported by a support structure, able to create a pressure differential across the skin at at least a portion of the access site. The device may also include, in some cases, a sensor supported by the support structure for determining at least one condition of the extractable medium from the subject, and optionally a signal generator supported by the support structure for generating a signal relating to the condition of the medium determined by the sensor.

Abstract: The present invention is generally directed to systems and methods for sampling fluids from subjects. The fluid may be any suitable bodily fluid, e.g., blood or interstitial fluid. In some cases, the subject is a patient. The subject may have a device that can be applied to the skin of the subject (e.g., by the subject, or another person), and the device is able to obtain a sample of fluid. The fluid may be stored within a reservoir in the device, and the fluid may be obtained from the subject at any convenient time, e.g., at home, away from a healthcare setting, etc. In some embodiments, the device, or a portion thereof, may be returned to a clinical and/or laboratory setting to analyze the fluid stored within the device.

Abstract: The present invention generally relates to receiving bodily fluid through a device opening. In one aspect, the device includes a flow activator arranged to cause fluid to be released from a subject. A deployment actuator may actuate the flow activator in a deployment direction, which may in turn cause fluid release from a subject. The flow activator may also be moved in a retraction direction by a retraction actuator. In one aspect, the device may include a vacuum source that may help facilitate fluid flow into the opening of the device and/or may help facilitate fluid flow from the opening to a storage chamber. In one aspect, a device actuator may enable fluid communication between the opening and the vacuum source and the flow activator may be actuated after the enablement of fluid communication.

Abstract: The present invention generally relates to receiving bodily fluid through a device opening. In one aspect, the device includes a flow activator arranged to cause fluid to be released from a subject. A deployment actuator may actuate the flow activator in a deployment direction, which may in turn cause fluid release from a subject. The flow activator may also be moved in a retraction direction by a retraction actuator. In one aspect, the device may include a vacuum source that may help facilitate fluid flow into the opening of the device and/or may help facilitate fluid flow from the opening to a storage chamber. In one aspect, a device actuator may enable fluid communication between the opening and the vacuum source and the flow activator may be actuated after the enablement of fluid communication.

Abstract: The present invention generally relates to receiving bodily fluid through a device opening. In one aspect, the device includes a flow activator arranged to cause fluid to be released from a subject. A deployment actuator may actuate the flow activator in a deployment direction, which may in turn cause fluid release from a subject. The flow activator may also be moved in a retraction direction by a retraction actuator. In one aspect, the device may include a vacuum source that may help facilitate fluid flow into the opening of the device and/or may help facilitate fluid flow from the opening to a storage chamber. In one aspect, a device actuator may enable fluid communication between the opening and the vacuum source and the flow activator may be actuated after the enablement of fluid communication.

Abstract: Techniques are provided to produce and use non-spherical colloidal particles with independently tuned size, shape, flexibility, and chemical properties. A pre-polymer mixture for forming hydrogel particles includes a percentage of PEGDA selected to impart a target stiffness to the particles and includes, a percentage of acrylic acid selected to impart an independent target chemical function to the particles. The mixture also includes a percentage of photo-initiator to polymerize PEGDA upon exposure to a light source to impart an independently selected target size or shape or both to the particles.

Abstract: The present invention generally relates to receiving bodily fluid through a device opening. In one aspect, the device includes a flow activator arranged to cause fluid to be released from a subject. A deployment actuator may actuate the flow activator in a deployment direction, which may in turn cause fluid release from a subject. The flow activator may also be moved in a retraction direction by a retraction actuator. In one aspect, the device may include a vacuum source that may help facilitate fluid flow into the opening of the device and/or may help facilitate fluid flow from the opening to a storage chamber. In one aspect, a device actuator may enable fluid communication between the opening and the vacuum source and the flow activator may be actuated after the enablement of fluid communication.

Abstract: The present invention generally relates to receiving bodily fluid through a device opening. In one aspect, the device includes a flow activator arranged to cause fluid to be released from a subject. A deployment actuator may actuate the flow activator in a deployment direction, which may in turn cause fluid release from a subject. The flow activator may also be moved in a retraction direction by a retraction actuator. In one aspect, the device may include a vacuum source that may help facilitate fluid flow into the opening of the device and/or may help facilitate fluid flow from the opening to a storage chamber. In one aspect, a device actuator may enable fluid communication between the opening and the vacuum source and the flow activator may be actuated after the enablement of fluid communication.

Abstract: The present invention generally relates to receiving bodily fluid through a device opening. In one aspect, the device includes a flow activator arranged to cause fluid to be released from a subject. A deployment actuator may actuate the flow activator in a deployment direction, which may in turn cause fluid release from a subject. The flow activator may also be moved in a retraction direction by a retraction actuator. In one aspect, the device may include a vacuum source that may help facilitate fluid flow into the opening of the device and/or may help facilitate fluid flow from the opening to a storage chamber. In one aspect, a device actuator may enable fluid communication between the opening and the vacuum source and the flow activator may be actuated after the enablement of fluid communication.

Abstract: In some embodiments, the present invention generally relates to the separation of blood within a device to form plasma or serum. In some embodiments, the present invention generally relates to the removal of fluids, such as blood, contained within a device. For example, a device may be applied to the skin of a subject to receive blood from the subject and pass the blood through a separation membrane, which separates the blood into plasma and a portion concentrated in blood cells. As another example, blood or plasma may be allowed to clot within the device and serum (the unclotted portion of the blood) may be withdrawn from the device. The device may contain, in some cases, a vacuum source such as a pre-packaged vacuum to facilitate receiving of blood and/or passage of the blood through the separation membrane to produce plasma or serum.

Abstract: Systems and methods for delivering to and/or receiving fluids or other materials, such as blood or interstitial fluid, from subjects, e.g., from the skin. Beading disruptors and/or capillaries may be used for facilitating the transport of fluids from a subject into a device. Beading disruptors may disrupt the “pooling” of bodily fluids such as blood on the surface of the skin and help influence flow in a desired way. A capillary may conduct flow of fluid in the device, e.g., to an inlet of a channel or other flow path that leads to a storage chamber. A vacuum (reduced pressure relative to ambient) may be used to receive fluid into the device, e.g., by using relatively low pressure to draw fluid into the inlet of a channel leading to a storage chamber. The vacuum source may be part of the device.

Abstract: The present invention generally relates to systems and methods for delivering and/or receiving a substance or substances such as blood, from subjects, e.g., from the skin and/or from other tissues of the body. In some cases, the device may contain a substance transfer component such as needles or microneedles, which can be inserted into the skin or another organ to deliver and/or receiving fluid or other substances from the subject. In some embodiments, the device may include an activator constructed and arranged to insert one or more substance transfer components into the skin or other organ. In certain cases, the device may also include a storage chamber for receiving a fluid received from the subject.

Abstract: The present invention generally relates to systems and methods for delivering and/or receiving a substance or substances such as blood, from subjects, e.g., to the skin and/or from the skin. In one aspect, the present invention is generally directed to devices and methods for receiving blood from a subject, e.g., from the skin, using devices including a substance transfer component (which may contain, for example, one or more microneedles), and a storage chamber having an internal pressure less than atmospheric pressure prior to receiving blood. In certain embodiments, substances may be received from and/or delivered to the subject with relatively little pain. The pain may be assessed, to for example, using pain scales such as the Wong-Baker FACES Pain Scale. In some cases, the device may be self-contained, and in certain instances, the device can be applied to the skin, and activated to receive blood from the subject.