Abstract: This invention this invention is a device and method for validating the identity of a liquid in a container that is transparent to light, while the liquid is in the container, without physically invading container. The liquid is particularly suited for validating vaccines such as the vaccine for COVID-19. The invention uses light from a refractometer and/or nephelometer, passing into and reflected out of the transparent wall of the container, to characterize the liquid.

Abstract: A nephelometer for determining the turbidity of a body of fluid in which a light beam is directed as an angled beam through the body and two light detectors measure the intensity of light scatter at two points in the beam. The two measurements are divided and scaled, and then the result is logarithmically amplified and displayed as the turbidity.

Abstract: A noninvasive method for estimating a concentration of a target analyte in a sample comprises generating a first and second (reference) radiation, a principal radiation and a target analyte carrier detection radiation; directing the first, second, principal and the target analyte carrier detection radiations at the sample which includes the target analyte; and detecting a first, second, principal and target analyte carrier detection amount of the radiation that leaves the sample. The method further comprises modulating the sample thickness in order to achieve time-wise or spatial target analyte concentration variation within the sample.

Abstract: The present invention pertains to the measurement of the refractive index of a medium, such as a fluid, through the wall of its container. The essential characteristic of the invention is that, by using at least two separate light paths that are of unequal length and that reflect from the wall/medium interface, it is possible to perform the measurement of the refractive index of the medium so that the result is insensitive to the color and thickness of the wall.

Abstract: A noninvasive method for estimating a concentration of a target analyte in a sample comprises generating a first and second (reference) radiation, a principal radiation and a target analyte carrier detection radiation; directing the first, second, principal and the target analyte carrier detection radiations at the sample which includes the target analyte; and detecting a first, second, principal and target analyte carrier detection amount of the radiation that leaves the sample. The method further comprises modulating the sample thickness in order to achieve time-wise or spatial target analyte concentration variation within the sample.

Abstract: A nephelometer for determining the turbidity of a body of fluid in which a light beam is directed as an angled beam through the body and two light detectors measure the intensity of light scatter at two points in the beam. The two measurements are divided and scaled, and then the result is logarithmically amplified and displayed as the turbidity.

Abstract: The present invention pertains to the measurement of the refractive index of a medium, such as a fluid, through the wall of its container. The essential characteristic of the invention is that, by using at least two separate light paths that are of unequal length and that reflect from the wall/medium interface, it is possible to perform the measurement of the refractive index of the medium so that the result is insensitive to the color and thickness of the wall.

Abstract: A noninvasive method for estimating a concentration of a target analyte in a sample comprises generating a first and second (reference) radiation, a principal radiation and a target analyte carrier detection radiation; directing the first, second, principal and the target analyte carrier detection radiations at the sample which includes the target analyte; and detecting a first, second, principal and target analyte carrier detection amount of the radiation that leaves the sample. The method further comprises modulating the sample thickness in order to achieve time-wise or spatial target analyte concentration variation within the sample.

Abstract: A method may include directing a radiation beam at a sample, the beam including two periods of radiation having different wavelengths, an analyte in a fluid within the sample having different absorption coefficients for the two different wavelengths, detecting the beam with a detector when the sample is in a first fluid state, the detector configured to generate an output signal proportional to an intensity of the beam at each of the two different wavelengths, detecting the beam with the detector when the sample is in a second fluid state, the sample transitioning from the first fluid state to the second fluid state by a pulsation of the sample, obtaining estimates of an amount of fluid at the first and second fluid states, and determining an analyte concentration estimate based on the output signal and the estimate of the amount of fluid at the first and second fluid states.

Abstract: A method and apparatus for noninvasively measuring the concentration of a target analyte in a sample matrix using a fiberless transflectance probe is described. It includes directing a beam of electromagnetic radiation, consisting of at least two components of different wavelengths, to the sample matrix and conducting the backscattered radiation to a detector which outputs a signal indicative of the differential absorption of the two wavelengths in the sample matrix. The transflectance probe comprises a tapered tubular housing having an inner reflective surface, an optical rod having an outer reflective surface, and a detection window which serves as an interface between the probe and the surface of the sample matrix. The method and apparatus described are particularly useful in measuring the concentration of glucose in tissue containing blood.

Abstract: A method and apparatus for noninvasively measuring the concentration of a target analyte in a sample matrix using a fiberless transflectance probe is described. It includes directing a beam of electromagnetic radiation, consisting of at least two components of different wavelengths, to the sample matrix and conducting the backscattered radiation to a detector which outputs a signal indicative of the differential absorption of the two wavelengths in the sample matrix. The transflectance probe comprises a tapered tubular housing having an inner reflective surface, an optical rod having an outer reflective surface, and a detection window which serves as an interface between the probe and the surface of the sample matrix. The method and apparatus described are particularly useful in measuring the concentration of glucose in tissue containing blood.

Abstract: An improved method for non-invasively measuring a concentration of a target analyte dissolved in a fluid flowing through a sample is presented. It includes directing a probe beam of electromagnetic radiation, having time multiplexed components of different wavelengths, where at least one of the time-multiplexed components consists of two different simultaneous wavelengths through the sample and measuring the difference of the absorption of the radiation of the time-multiplexed components at different sample states. During sample state changes, the amount of fluid containing the target analyte within the sample is changing, varying the total amount of target analyte in the sample, and the absorption properties of the sample. The sample states may be produced by compressing and uncompressing the tissue sample. The method is useful in measuring the concentration of a target analyte, such as glucose, in tissue containing blood.

Abstract: An improved method for non-invasively measuring a concentration of a target analyte dissolved in a fluid flowing through a sample is presented. It includes directing a probe beam of electromagnetic radiation, consisting of time multiplexed components of different wavelengths, where at least one of the time-multiplexed components consists of two different simultaneous wavelengths, whose intensity relation defines the effective wavelength of their combination, through the sample and measuring the difference of the absorption of the radiation of the time-multiplexed components at different sample states. During sample state changes, the amount of fluid containing the target analyte within the sample is changing, which varies the total amount of target analyte in the sample, as well as the absorption properties of the sample. The sample states are produced, for instance, by compressing and uncompressing the tissue sample.

Abstract: An improved method for non-invasively measuring a concentration of a target analyte dissolved in a fluid flowing through a sample is presented. It includes directing a probe beam of electromagnetic radiation, consisting of time multiplexed components of different wavelengths, through the sample and measuring the difference of the absorption of the radiation at at least one wavelength pair at different sample states. During sample state changes, the amount of fluid containing the target analyte within the sample is changing, which varies the total amount of target analyte in the sample, as well as the absorption properties of the sample. The sample states are produced, for instance, by compressing and uncompressing the tissue sample. The accuracy of the presented method is enhanced by including continuous estimation of the amount of the fluid containing the target analyte within the sample, and measurement of the variations of the absorption at a wavelength at which the target analyte absorbs significantly.

Abstract: An improved method for non-invasively measuring a concentration of a target analyte dissolved in a fluid flowing through a sample is presented. It includes directing a probe beam of electromagnetic radiation, consisting of time multiplexed components of different wavelengths, through the sample and measuring the difference of the absorption of the radiation at at least one wavelength pair at different sample states. During sample state changes, the amount of fluid containing the target analyte within the sample is changing, which varies the total amount of target analyte in the sample, as well as the absorption properties of the sample. The sample states are produced, for instance, by compressing and uncompressing the tissue sample. The accuracy of the presented method is enhanced by including continuous estimation of the amount of the fluid containing the target analyte within the sample, and measurement of the variations of the absorption at a wavelength at which the target analyte absorbs significantly.

Abstract: The object of the invention is a method for correcting a temperature dependent dispensing error occurring during liquid dispensing, such as pipetting, as well as a liquid dispensing device, such as a pipette, having a higher degree of accuracy. According to the method the dispensing takes place by means of two chambers connected to each other over a gas passage. The first chamber communicates, in addition to the gas passage, with the liquid to be dispensed, and the second chamber is gas tight except for the gas passage. In order to receive liquid in the dispensing device, the volume of the second chamber is increased, resulting in gas flowing therein from the first chamber, and in turn, liquid to be dispensed flowing into the first chamber until a pressure equilibrium between the chambers has been reached.

Abstract: The present invention relates to the determination of an analyte or multiple analytes in blood using information derived from the differential optical absorption spectra of blood. Specifically, the information is derived from the differential spectra of tissue before and immediately after the volume of blood in the tissue has been changed.

Abstract: To deterine glucose or other constituents of the human or animal body, near-infrared radiation containing two alternating wavelengths that have equal extinction coefficients in the tissue is directed onto a sample area of the body. The intensity relation of the two different wavelengths is adjusted so as to balance the two wavelength detected signals. The extracellular-to-intracellular fluid ratio of the tissue is changed or is allowed to change, and the alternating component of the transmitted beam power is measured. The amplitude of the alternating-current (AC) signal given by the detector represents glucose concentration or the difference from a preset reference concentration.

Abstract: To determine glucose or other constituents of the human or animal body, a stabilized near-infrared radiation beam containing two alternating wavelengths that have approximately equal extinction coefficients in the tissue, is directed onto the sample area, the transmitted signal alternating component is zeroed by tuning one of the wavelengths, the extracellular-to-intracellular fluid ratio of the tissue is changed by exerting varying mechanical pressure on the tissue, or the ratio is allowed to change as a result of the natural pulsation. The alternating component of the transmitted beam power is measured in the changed fluid ratio state. The amplitude of the alternating-current (AC) signal given by the detector, is taken to represent glucose concentration or the difference from a preset reference concentration.

Abstract: A non-invasive system for measuring the concentration of an analyte, such as glucose, in an absorbing matrix is described. The system directs beams of light at the matrix using an analyte sensitive wavelength and an analyte insensitive wavelength. The principles of photoplethysmography are applied to measure the change in light intensity caused by matrix absorption before and after the blood volume change caused by the systolic phase of the cardiac cycle. The change in light intensity is converted to an electrical signal which is used to adjust the light intensity and as a measure of analyte concentration.