Spectrometry system

Inventors

Allsworth, Max • Few, Julian William • Marquez Sillero, Isabel • Pearson, Jonathan

Assignees

Owlstone Medical Ltd • Owlstone Inc

Abstract

We describe a method and apparatus for detecting humidity using a Field Asymmetric Ion Mobility Spectrometry (FAIMS) system. The system may comprise an ionizer for generating ions within a gas sample, wherein each ion has an associated ion mobility; an ion filter for separating the ions by applying a compensation field and a dispersion field to the generated ions; a detector for detecting an output from the ion filter; and a processor. The processor may be configured to extract a spectrum of peak intensity of the detected output as a function of the compensation field and the dispersion field; calculate a turning point for the extracted spectrum; determine operating parameters of the field asymmetric ion mobility system; obtain, from a database, a plurality of known turning points each of which have an associated humidity and each of which were obtained using a field asymmetric ion mobility system having operating parameters aligned with the determined operating parameters; and determine the humidity by comparing the calculated turning point with known turning points.

Core Innovation

The invention relates to determining humidity using a field asymmetric ion mobility system. Ions are generated within a gas sample flowing through the field asymmetric ion mobility system, and the generated ions are subjected to a compensation field and a dispersion field. An output ion current is measured, and a spectrum of peak intensity of the measured output is extracted as a function of the compensation field and the dispersion field.

A turning point is calculated for the extracted spectrum. Operating parameters of the field asymmetric ion mobility system are determined, and a database is obtained that includes a plurality of known turning points, where each known turning point has an associated humidity value. Each known turning point in the database is obtained using a field asymmetric ion mobility system having operating parameters aligned with the determined operating parameters.

A humidity value for the gas sample is determined by comparing the calculated turning point with known turning points from the database. The disclosed approach also includes optional refinements for extracting or deriving humidity, such as using peak width or peak location and using range-based extrapolation based on one or more ranges defined by known turning points. The database construction ties turning points to humidity under operating-parameter settings aligned to the conditions used during measurement.

Claims Coverage

The partial content includes two independent claims that collectively cover a humidity-determination method using FAIMS turning-point matching against a humidity-associated database, and a corresponding FAIMS spectrometry system with ionization, ion filtering, detection, processing, and database-based humidity determination. Across these independent claims, the core inventive features center on extracting a peak-intensity spectrum as a function of compensation and dispersion fields, calculating a turning point, aligning operating parameters to obtain humidity-associated turning points, and determining humidity by comparison.

The independent claims require FAIMS operation that produces a peak-intensity spectrum indexed to compensation and dispersion fields, computation of a turning point from that spectrum, and retrieval of humidity-associated known turning points from a database built under operating parameters aligned with the current measurement conditions, followed by humidity determination by comparison of turning points.

Stated Advantages

Documented Applications

No documented applications found