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PH Photothermal Spectrometer And Performing PH Photothermal Spectroscopy

Patent Number: 11,624,664

Abstract

A pH photothermal spectrometer includes a container that receives an analyte medium and pH-sensitive chromophore. An excitation fiber and optical thermometer are disposed in the container. The optical thermometer include a light receiver disposed on a temperature detector fiber.

patent description

Disclosed is a pH photothermal spectrometer for performing pH photothermal spectroscopy, the pH photothermal spectrometer comprising a container comprising an interior bounded by a wall of the container, such that the container receives an analyte medium and a pH-sensitive chromophore, the pH-sensitive chromophore comprises an optical absorption spectrum that adjusts to a pH of the analyte medium, the analyte medium comprising a analyte temperature TA; and optionally receives a fiber encapsulation matrix in which are disposed the analyte medium and the pH-sensitive chromophore; an excitation fiber disposed in the container in optical communication with the pH-sensitive chromophore and that receives a first excitation light comprising a first wavelength and a second excitation light comprising a second wavelength; and communicates the first excitation light and the second excitation light to the pH-sensitive chromophore, such that the pH-sensitive chromophore receives the first excitation light and the second excitation light; and absorbs a first amount A1 of the first excitation light and a second amount A2 of the second excitation light based on the pH of the analyte medium such that absorption of the first excitation light or the second excitation light increases the analyte temperature TA of the analyte medium; and an optical thermometer disposed in the container and comprising a temperature detector fiber that receives a probe light comprising a probe light wavelength in a first optical amount O1; and receives a reflected light comprising the probe light wavelength from a light receiver; and a light receiver disposed on a terminus of the temperature detector fiber in optical communication with the temperature detector fiber and in thermal communication with the analyte medium; and comprising a receiver temperature TR that adjusts to match the analyte temperature TA; and an optical resonance OR at a resonance wavelength LR that changes in response to a change in the receiver temperature TR, such that the light receiver receives the probe light from the temperature detector fiber; produces, from the probe light, a reflected light in a second optical amount O2 and comprising the probe light wavelength, such that the second optical amount O2 of the reflected light depends on the receiver temperature TR of the light receiver, so that a ratio of the first optical amount O1 to the second optical amount O2 provides a pH of the analyte medium; and communicates the reflected light to the temperature detector fiber; and the temperature detector fiber receives the reflected light from the light receiver.

Disclosed is a process for performing pH photothermal spectroscopy with a pH photothermal spectrometer, the process comprising receiving, by the excitation fiber, the first excitation light that comprises the first wavelength and the second excitation light that comprises the second wavelength; contacting the pH-sensitive chromophore with the analyte medium; adjusting the optical absorption spectrum of the pH-sensitive chromophore in response to the pH of the analyte medium; communicating the first excitation light and the second excitation light from the excitation fiber to the pH-sensitive chromophore; receiving, by the pH-sensitive chromophore, the first excitation light and the second excitation light; absorbing, by the pH-sensitive chromophore, the first amount A1 of the first excitation light based on the pH of the analyte medium; absorbing, by the pH-sensitive chromophore, the second amount A2 of the second excitation light based on pH of the analyte medium; adjusting the analyte temperature TA of the analyte medium in response to the pH-sensitive chromophore absorbing the first excitation light and the second excitation light; adjusting the receiver temperature TR of the light receiver to match the analyte temperature TA of the analyte medium in response to adjusting the analyte temperature TA of the analyte medium; receiving, by the light receiver, the probe light in the first optical amount O1 from the temperature detector fiber; producing, by the light receiver from the probe light, the reflected light in the second optical amount O2 that depends on the receiver temperature TR of the light receiver, the reflected light comprising the probe light wavelength; and determining the pH of the analyte medium from a ratio of the first optical amount O1 to the second optical amount O2 to perform pH photothermal spectroscopy.

Created September 21, 2022, Updated December 15, 2023