Ammonia detection and measurement device
AssigneePhotonic BioSystems, Inc.
InventorsGamal E. Khalil, David L. Putnam, Todd W. Hubbard
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Abstract
There is disclosed an apparatus and method for detecting and measuring volatile acidic or basic components including ammonia, ammonium, or volatile amines (compound) in a gas or liquid state fluid. Specifically, the present invention provides a PTFE-carrier solid phase indicator film having an ammonia-sensitive indicator dye embedded therein, such that the dye moiety changes color or spectral properties upon exposure to the compound to be detected.
Claims23
A reversible-in-gas sensor for detecting and measuring volatile basic compounds in a gaseous environment, comprising:
- a polytetraflouroethylene (PTFE) solid substrate;
- and
- an ammonia-sensitive indicator dye having measurable spectral characteristics immobilized, using a method comprising a volatile acid vapor-treatment, in or on the polytetraflouroethylene (PTFE) solid substrate, the immobilized ammonia-sensitive indicator dye being capable of undergoing a color change in spectral characteristics when exposed to a gaseous environment comprising a volatile basic compound, and further capable of color reversion in a gaseous environment.
A method for detecting and measuring volatile basic compounds in a gaseous environment, comprising:
- (a) placing a sensor in a gaseous environment comprising a volatile basic compound, wherein the sensor includes an ammonia-sensitive indicator dye having measurable spectral characteristics immobilized, using a method comprising a volatile acid vapor-treatment, in or on the polytetraflouroethylene (PTFE) solid substrate, the immobilized ammonia-sensitive indicator dye capable of undergoing a color change in spectral characteristics when exposed to the gaseous environment comprising the volatile basic compound, and further capable of color reversion in a gaseous environment;
- and
- (b) determining an amount of volatile basic chemical compound present by measuring a reversible spectral change in the wavelengths of light that are absorbed or emitted by the ammonia-sensitive indicator dye, or by observing a color change.
A method of making a reversible-in-gas sensor for detecting and measuring volatile basic compounds in a gas, comprising:
- dipping a polytetraflouroethylene (PTFE) solid substrate into a bath of a reversible-in-gas, ammonia-sensitive indicator dye having measurable spectral characteristics;
- allowing the indicator dye to adhere to the surface of the solid substrate to form a wet sensor composition;
- allowing the wet sensor composition to dry;
- immersing the dried sensor composition into the vapor phase of a fuming hydrochloric acid solution;
- immersing the sensor in a water bath;
- and
- allowing the sensor to dry.
A method for detecting and measuring ammonia gas leaks inside cold food storage rooms, comprising:
- (a) placing a sensor in a gaseous environment inside a cold food storage room for detecting ammonia gas leaks, wherein the sensor comprises an ammonia-sensitive indicator dye having measurable spectral characteristics immobilized, using a method comprising a volatile acid vapor-treatment step, in or on a polytetraflouroethylene (PTFE) solid substrate, the immobilized ammonia-sensitive indicator dye being capable of undergoing a color change in spectral characteristics when exposed to a gaseous environment comprising ammonia, and further capable of color reversion in a gaseous environment;
- and
- (b) determining the amount of ammonia gas present by measuring a reversible spectral change in the wavelengths of light that are absorbed or emitted by the ammonia-sensitive indicator dye, or by observing a color change.
A reversible-in-gas sensor comprising:
- a polytetraflouroethylene (PTFE) solid substrate;
- and
- an ammonia-sensitive indicator dye having measurable spectral characteristics immobilized, using a method comprising a volatile acid vapor-treatment, in or on the polytetraflouroethylene (PTFE) solid substrate, the immobilized ammonia-sensitive indicator dye being capable of:
- a color change in spectral characteristics when exposed to a gas comprising a volatile basic compound;
- and
- color reversion in a gaseous environment comprising a volatile acidic compound.
A method for detecting and measuring volatile acidic or basic compounds in a gaseous environment, comprising:
- placing a sensor in a gaseous environment, the sensor comprising an ammonia-sensitive indicator dye reversibly configurable in an acid form and a basic form, the dye having measurable spectral characteristics immobilized, using a method comprising one of a volatile acid vapor-treatment and a volatile basic vapor-treatment, in or on the polytetraflouroethylene (PTFE) solid substrate, the volatile acid vapor-treatment configuring the dye in the acid form, the volatile basic vapor-treatment configuring the dye in the basic form,
- when in the acid form, exposure to a volatile basic chemical compound in the gaseous environment causing the dye to undergoing a reversible color change in spectral characteristics;
- when in the basic form, exposure to a volatile acid chemical compound in the gaseous environment causing the dye to undergoing a reversible color change in spectral characteristics;
- and
- determining an amount of volatile acid or basic chemical compound present in the gaseous environment by measuring a reversible spectral change in the wavelengths of light that are absorbed or emitted by the ammonia-sensitive indicator dye, or by observing a color change.
Dependencies are inferred from the claim text.