Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-11789031-B2
Publication Date
2023-10-17
Expiration Date
Abstract
The present invention relates generally to a slope spectroscopy standards and methods of making slope spectroscopy standards, specifically standards and methods of developing standards specifically for variable pathlength (slope) measurements.
Core Innovation
The disclosure relates to creating and using slope spectroscopy standards for variable path length spectrophotometry rather than adapting conventional UV/Vis absorbance standards. It uses variable path length spectroscopy to generate absorbance values as a function of path length and then produces an absorbance-vs-pathlength regression slope for each standard. The standards are selected to provide stable, measurable slopes across a defined absorbance range.
Standards are developed by measuring and validating absorbance-vs-pathlength regression slopes over multiple path lengths, and by selecting standards with target minimum slope ranges. The disclosure describes establishing NIST-traceable certified slope values, including quantified uncertainty for the certified slope. Performance evaluation includes comparing measured slope to certified slope and using repeatability metrics based on standard deviation/RMS and related residual metrics.
The disclosure also describes standard development for single compounds and multi-component mixtures. Multi-component standards are described in the context of including caffeine together with an additional drug-analog absorber to mimic antibody/drug conjugate ratio effects, including for drug-to-antibody ratio mimicry. The disclosed standards are used to assess spectrophotometer fitness by measuring slope with variable path length spectroscopy and comparing pre/post adjustments.
Claims Coverage
The partial content includes two independent method claims. Each claim centers on variable path length spectroscopy testing, deriving slope or regression-based correlation, and comparing results to certified or predetermined values, using a standard selected from methylxanthine or specified salts.
Variable path length spectroscopy slope fitness determination using certified slope comparison
Testing the spectrophotometer by measuring absorbance values for a predetermined concentration of a standard at a predetermined wavelength and multiple pathlengths using variable path length spectroscopy; calculating a slope value of the standard from a linear regression of the absorbance values at the multiple pathlengths; comparing the calculated slope value to a certified slope value or to the corresponding slope value on a standard curve to determine the state of fitness of the spectrophotometer.
Variable path length spectroscopy regression correlation fitness determination
Testing the spectrophotometer by measuring absorbance values for a predetermined concentration of a standard at a predetermined wavelength and multiple pathlengths using variable path length spectroscopy; comparing the measured absorbance values at the multiple pathlengths to a predetermined linear regression of the standard and determining the correlation between the measured values and the predetermined values to determine the state of fitness of the spectrophotometer.
Across the independent claims, spectrophotometer fitness is determined using variable path length spectroscopy with a predetermined standard at a predetermined wavelength, with fitness determined either by slope comparison to certified or standard-curve slope or by correlation to a predetermined linear regression.
Stated Advantages
Enables determining a state of fitness of a spectrophotometer by comparing calculated slope to a certified slope value or a slope on a standard curve.
Enables determining a state of fitness of a spectrophotometer by correlating measured absorbance values at multiple pathlengths with a predetermined linear regression.
Uses standards having NIST-traceable certified slope values with quantified uncertainty.
Documented Applications
Assessing spectrophotometer fitness by measuring slope with variable path length spectroscopy and comparing results to certified values, including evaluating pre/post adjustments.
Developing standards for single compounds and multi-component mixtures, including multi-component standards used for antibody/drug conjugate (ADC) ratio mimicry via drug-to-antibody ratio mimicry.
Interested in licensing this patent?