Abstract: Described are devices, methods, and kits for non-invasively measuring glucose. In general, the devices comprise skin patches for placement on a skin surface and measurement devices for measuring glucose collected in the patches. The patches may include an adhesive material, a collection layer, an interface layer, and a sweat-permeable membrane. The sweat-permeable membrane is configured to act as a barrier to epidermal contaminants and glucose brought to the skin surface via diffusion. In this way, non-correlatable skin surface glucose will not be measured. The patches may further include components to induce a local sweat response. The measurement device typically includes a display, a processor, and a measurement mechanism. The methods typically include the steps of wiping the skin surface with a wipe containing at least one solvent for removing glucose, placing a patch on a skin surface, and measuring glucose collected in the patch. Kits comprising the patch and measurement device are also described.

Abstract: Described here are patches, systems, and methods for measuring glucose. In general, the patches comprise a microfluidic collection layer and a detector, and the systems comprise a patch and a measurement device. Some methods for measuring glucose comprise cleaning the skin surface, collecting sweat from the skin surface using a microfluidic collection device, and measuring the collected glucose. Other methods comprise cleaning the skin surface, collecting sweat in a patch comprising a microfludic collection layer, and measuring glucose collected in the patch. Still other methods comprise cleaning the skin surface, collecting a first sweat sample from the skin surface in a patch comprising a microfludic collection layer and a detector layer, transferring the first sweat sample from the collection layer to the detector layer, measuring glucose in the first sweat sample, and repeating the collection, transferring, and measuring steps at least once.

Abstract: Described here are patches, systems, and methods for measuring glucose. In general, the patches comprise a microfluidic collection layer and a detector, and the systems comprise a patch and a measurement device. Some methods for measuring glucose comprise cleaning the skin surface, collecting sweat from the skin surface using a microfluidic collection device, and measuring the collected glucose. Other methods comprise cleaning the skin surface, collecting sweat in a patch comprising a microfludic collection layer, and measuring glucose collected in the patch. Still other methods comprise cleaning the skin surface, collecting a first sweat sample from the skin surface in a patch comprising a microfludic collection layer and a detector layer, transferring the first sweat sample from the collection layer to the detector layer, measuring glucose in the first sweat sample, and repeating the collection, transferring, and measuring steps at least once.

Abstract: Described here are patches, systems, and methods for measuring glucose. In general, the patches comprise a microfluidic collection layer and a detector, and the systems comprise a patch and a measurement device. Some methods for measuring glucose comprise cleaning the skin surface, collecting sweat from the skin surface using a microfluidic collection device, and measuring the collected glucose. Other methods comprise cleaning the skin surface, collecting sweat in a patch comprising a microfludic collection layer, and measuring glucose collected in the patch. Still other methods comprise cleaning the skin surface, collecting a first sweat sample from the skin surface in a patch comprising a microfludic collection layer and a detector layer, transferring the first sweat sample from the collection layer to the detector layer, measuring glucose in the first sweat sample, and repeating the collection, transferring, and measuring steps at least once.

Abstract: Described are devices, methods, and kits for non-invasively measuring glucose. In general, the devices comprise skin patches for placement on a skin surface and measurement devices for measuring glucose collected in the patches. The patches may include an adhesive material, a collection layer, an interface layer, and a sweat-permeable membrane. The sweat-permeable membrane is configured to act as a barrier to epidermal contaminants and glucose brought to the skin surface via diffusion. In this way, non-correlatable skin surface glucose will not be measured. The patches may further include components to induce a local sweat response. The measurement device typically includes a display, a processor, and a measurement mechanism. The methods typically include the steps of wiping the skin surface with a wipe containing at least one solvent for removing glucose, placing a patch on a skin surface, and measuring glucose collected in the patch. Kits comprising the patch and measurement device are also described.

Abstract: A non-invasive analyte measurement device having increased signal to noise ratios is disclosed herein. Typically, the glucose measurement device is self-normalizing in that it does not employ an independent reference sample in its operation. The device uses attenuated total reflection (ATR) infrared spectroscopy. The device is used on a fingertip and compares two specific regions of a measured infrared spectrum to determine the blood glucose level of the user. This device is suitable for monitoring glucose levels in the human body and is especially beneficial to users having diabetes mellitus. Moreover, the device utilizes a periodically modulated optical signal and at least one lock-in amplifier to correlate the signals to gain maximum sensitivity and an increased signal-to-noise ratio. The device and procedure can be used for other analyte materials which exhibit unique mid-IR signatures of the type described herein and that are found in appropriate regions of the outer skin.

Abstract: A method and apparatus for analyzing a sample wherein at least two orthogonally polarized, intensity and phase modulated laser beams with different wavelengths and frequencies of intensity and phase modulation are directed onto the sample, and the signals derived from the laser beams which interact with the sample are synchronously demodulated to determine characteristics of the sample such as index of refraction, absorption coefficient and film thickness. A reference beam can be provided to correct for noise and drift.

Abstract: A method and an apparatus for the analysis of particles contained in a material, such as particles in a fluid or on a surface, such as the surface of a semiconductor, by two orthogonally polarized, intensity and phase modulated laser beams, wherein the detected scattered light is synchronously demodulated. The apparatus comprises a laser source producing a polarized laser beam, a state of polarization modulator, and a photoreceiver for detecting light scattered by particles at an angle to the incident light. A synchronous demodulator, such as a dual channel lock-in amplifier, separates the intensity and phase modulated portions of the scattered signals. A reference unit for detecting a non-scattered light produced by the sample to provide a reference is preferably provided, as well. The size, index of refraction and identity, of the particles, for example, can be determined.