Breath analyzer and urea breath test method

Abstract

The present invention provides an improved breath analyzer and breath testing method for determining the presence or absence of disease in humans, including, but not limited to, the bacterium H. pylori in the subject's digestive tract.

Description

[Technical field]

[0001] Related Applications This application claims priority to International PCT Application No. PCT / US2019 / 065550, filed December 10, 2019, and also claims priority to U.S. Provisional Application No. 62 / 879,345, filed July 26, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application generally relates to a breath analyzer and a breath testing method for detecting gases in a human breath sample to determine the presence or absence of disease in the subject's digestive tract, in some cases including, but not limited to, Helicobacter pylori. [Background technology]

[0003] Helicobacter pylori ("H. pylori") affects approximately two-thirds of the world's population, causes a large proportion of chronic gastritis and peptic ulcers, is the leading cause of gastric cancer, and is the third leading cause of cancer deaths worldwide. The prevalence of H. pylori has declined in Western countries since its discovery in 1982, but remains at very high levels in Eastern Europe, Asia, and the Asia-Pacific region, affecting more than 80% of young adults and children. Eradication of H. pylori and prevention of gastric cancer is most often achieved with a combination of antibiotics and proton pump inhibitors (PPIs). One of the key properties of H. pylori is that it is rich in the enzyme urease, which hydrolyzes urea. When H. pylori in the stomach is exposed to urea, it converts urea to CO2 and NH3, both of which reach the lungs via the bloodstream and are exhaled during exhalation. The breakdown of urea is described by the following equation; CO(NH2)2+H2O-urease->CO2+2NH3

[0004] Detection of H. pylori can be achieved by invasive and non-invasive diagnostic methods. Invasive methods include: 1) upper gastrointestinal endoscopy with biopsy for culture and rapid urease test (CLO test), and 2) blood test for serum antibodies to H. pylori. The advantages of invasive methods are that the diagnosis is accurate by testing tissue from the stomach containing H. pylori, and that serum antibodies are accurate. The disadvantages are: a) endoscopy is costly, inconvenient, and risky; b) misdiagnosis due to failure to obtain tissue from the actual site of the stomach containing H. pylori; and c) serum antibodies to H. pylori do not confirm eradication (they persist for a long time regardless of whether H. pylori is present in the patient).

[0005] Currently known non-invasive methods are: 1) 13 C Urea breath test ( 13 C UBT), which is considered the gold standard breath test, and 2) stool testing for H. pylori antigen. Their advantages are a) the non-invasive nature of these methods, and b) the simplicity of the conventional 13 C UBT has high sensitivity (95%) and specificity (95%). 13 The disadvantages of C UBT are a) the high cost of the equipment ($25,000, Otsuka America POCone infrared spectrometer), which requires operation by a professional who charges a fee; b) 13 The main limitations of H. pylori diagnostics are a) the high cost of C-labeled urea, c) the relatively high cost of the breath test kit ($110), and d) its very limited availability as a commercial product directly to the consumer at the point of care. Stool testing for H. pylori antigens is a) cumbersome and b) has rather low sensitivity (85%) and specificity (85%). The shortcomings of both invasive and non-invasive diagnostic methods have significantly limited the detection and subsequent eradication of H. pylori worldwide.

[0006] 13 C UBT is catalyzed by the abundant enzyme urease 13 C-labeled urea ( 13CO(NH2)2) and in the breath as follows: 13 It is based on the ability of H. pylori to produce CO2 and ammonia (NH3). 13 CO(NH2)2+H2O-urease-> 13 CO2+2NH3

[0007] Conventional 13 C UBT is 13 C-labeled urea meal (pranactin citric drug powder), the first bag for baseline fasting breath sample, and ( 13 The sample is provided as a kit containing a second bag for a postprandial breath sample (C-labeled urea). The bag is either shipped to a central laboratory or tested in the provider's office by trained personnel if they have the necessary equipment. 13 C UBT is 13 in an individual's breath after ingestion of C-labeled urea 13 CO2 / 12 Measure the ratio of CO2, which is the delta to baseline fasting exhaled CO2. 13 The use of C-labeled urea (instead of unlabeled urea) allowed the determination of the amount of urea produced in the exhaled air. 13 CO2 caused by H. pylori 13 This is needed to demonstrate that the CO2 is coming only from the breakdown of C-labeled urea and not from other sources within the body (e.g., muscle) that release CO2, a naturally occurring isotope of carbon. 13 Although C is encountered in nature, it accounts for only 1.8% of the total carbon. Therefore, 13 The possibility that CO2 is a product other than the hydrolysis of H. pylori urea is negligible.

[0008] The above 13 The C UBT procedure is as follows: a) the individual refrains from antibiotics, PPIs, bismuth, and sucralfate for two weeks; b) on the day of the test, the individual fasts (does not take anything by mouth) for one hour; c) the individual 13 C) exhale into a bag provided by the UBT provider; d) the individual 13C urea meal is ingested; e) 20 minutes after ingestion, the individual exhales into a bag provided by the provider; f) a specialized health care provider collects these bags and runs them through a spectrometer if a spectrometer is available on-site, or sends them to a central laboratory for testing; g) the individual is notified of the results within 48 hours if the bags are sent to a central laboratory, or within minutes if a spectrometer is available on-site.

[0009] As described in this disclosure, it would be desirable to provide a handheld breath analysis device that is easy to operate by non-professional personnel, that performs a novel urea breath test (UBT) by measuring both NH3 and CO2 (e.g., simultaneously) in a single breath sample, and that is inexpensive (e.g., $40-60 per device and test). It would also be desirable to provide such a device that provides immediate results at the point of care, providing results directly to the consumer via over-the-counter (OTC) or online sales. Additionally, 13 It would be desirable to provide a breath test that utilizes either 1C-labeled urea, or inexpensive (e.g., less than $1 per test) unlabeled urea. Summary of the Invention [Problem to be solved by the invention]

[0010] Certain embodiments of the present disclosure provide a breath analyzer. The breath analyzer includes an input, a first sensor, and a second sensor. The input is configured to receive a breath sample, and the first sensor and the second sensor are each configured to contact the breath sample. In some embodiments, the breath analyzer has two separate channels. In such a case, the breath sample is configured to move from the input to each of the first sensor and the second sensor via the separate channels. The first sensor includes a first conductive polymer and a conductive material. The first conductive polymer is in contact with the conductive material and has a resistivity that increases in response to an increase in ammonia concentration. The second sensor includes a second conductive polymer and a conductive material. In some embodiments, the conductive material of the first sensor and / or the second sensor includes a plurality of electrodes. In some cases, the plurality of electrodes includes wires arranged in a spiral configuration. In other embodiments, the plurality of electrodes includes wires arranged in a rectangular configuration. The second conductive polymer is in contact with the conductive material and has a resistivity that increases in response to an increase in ammonia concentration. 12 CO2 and 13 The second conductive polymer has a resistivity that increases in response to an increase in the concentration of CO2. The second conductive polymer includes a sulfonated polyaniline blended with polyethylene oxide. In some cases, the ratio of polyethylene oxide to sulfonated polyaniline is 10% to 30% by weight (e.g., about 30% by weight). In certain embodiments, the sulfonated polyaniline is synthesized from an emeraldine form of polyaniline polymer. The breath analyzer further includes a processor and an electrical circuit operably connecting the first sensor and the second sensor to the processor. The processor detects the resistivity of the electrical circuit and uses the resistivity to determine the total concentration of ammonia in the breath sample as well as the concentration of ammonia in the breath sample. 12 CO2 and 13 Calculate the total concentration of CO2. In some embodiments, the breath analyzer is in wireless communication with a remote device.

[0011] Another embodiment of the present disclosure provides a breath test method, comprising the steps of providing a breath analyzer (which may be any breath analyzer described in the present disclosure, including, for example, the breath analyzer described in the previous paragraph). The method further comprises: prompting the subject to exhale a baseline breath sample into the breath analyzer; allowing the processor to measure the resistivity of the first sensor that occurs when the baseline breath sample contacts the first sensor; and allowing the processor to measure the resistivity of the second sensor that occurs when the baseline breath sample contacts the second sensor. The method also comprises providing the subject with a meal or capsule containing urea (the urea is either 13C-labeled or unlabeled), and then prompting the subject to exhale a breath sample after ingesting urea into the breath analyzer. The method additionally includes enabling the processor to measure a resistivity of the first sensor that occurs when the post-urea breath sample contacts the first sensor, enabling the processor to measure a resistivity of the second sensor that occurs when the post-urea breath sample contacts the second sensor, and comparing the measured resistivity of the baseline breath sample to the measured resistivity of the post-urea breath sample. The method further includes calculating a difference between the resistivity of the first sensor of the baseline breath sample and the measured resistivity of the first sensor of the post-urea breath sample, and calculating a difference between the resistivity of the second sensor of the baseline breath sample and the measured resistivity of the second sensor of the post-urea breath sample. Additionally, the method includes calculating a difference in the resistivities of the first sensor (e.g., NH 3( ppb) and the difference in resistivity of the second sensor (e.g., CO2 or 13 and then displaying a final result as positive for H. pylori if the difference between the resistivity measured after urea and the baseline measured resistivity of the first sensor and the second sensor is a positive number, and negative for H. pylori if the difference between the resistivity measured after urea and the baseline measured resistivity of the first sensor and the second sensor is zero or a negative number.

[0012] Certain other embodiments of the present disclosure provide a method for detecting H. pylori in the gastrointestinal tract of a subject, the method comprising: collecting a baseline breath sample from the subject using a breath analyzer; and determining, using the breath analyzer, the total amount of ammonia and 12 CO2 and 13 The method further includes providing the subject with a meal containing a predetermined amount of natural urea or labeled urea. The method further includes collecting a post-urea breath sample from the subject using a breath analyzer, and determining the total amount of ammonia and CO2 present in the post-urea breath sample using the breath analyzer. 12 CO2 and 13 The method further comprises determining the total amount of ammonia and CO2 present in the breath sample after urea ingestion. 12 CO2 and 13 The total amount of CO2 was measured by a predetermined amount, along with the total amount of ammonia present in the baseline breath sample. 12 CO2 and 13 If the total amount of CO2 exceeds the total amount of CO2, it indicates the presence of H. pylori in the subject's digestive tract. The breath analyzer used in this method can be any breath analyzer described in this disclosure (e.g., including the breath analyzer described above, in which the second conductive polymer comprises sulfonated polyaniline blended with polyethylene oxide). [Brief description of the drawings]

[0013] [Figure 1] The acid-base (emeraldine salt (ES)-emeraldine base (EB)) transition of polyaniline is shown. [Diagram 2] 1 illustrates an embodiment of a PANI-CSA gas sensor. [Diagram 3] 1 is a graph showing the change in sensor conductivity for one embodiment of the NH3 sensor. [Figure 4] 4 is a graph showing the change in current due to the change in conductivity of the sensor of FIG. 3. [Diagram 5]1 shows the DropSens flow cell setup. [Figure 6] 1 is a calibration plot of CO2 showing the change in conductivity of the NH3 sensor of the present disclosure based on the change in the percentage of CO2. [Figure 7] 1 is a graph showing the sensitivity of the PANI-CSA sensor of the present disclosure to certain gases. [Figure 8] 1 shows a CO2 sensor with PPY-DBSA coated on a gold finger electrode. [Figure 9] 1 is a graph showing how the current to a PPY-DBSA sensor of the present disclosure changes upon exposure to CO 2 . [Figure 10] 1 shows the calibration of the PPY-DBSA sensor of the present disclosure. [Figure 11] 1 shows the effects of CO 2 , O 2 , H 2 O, and air on the PPY-DBSA sensor of the present disclosure. [Figure 12] FIG. 1 shows a bench prototype schematic diagram of one embodiment of a breath analyzer according to the present disclosure, comprising both a PPY-DBSA sensor and a PANI-CSA sensor. [Figure 13] 1 illustrates a diversion valve for use in the multi-sensor system of the present disclosure. [Figure 14] FIG. 1 is a schematic diagram illustrating a diversion valve for use in the multi-sensor system of the present disclosure. [Figure 15] 1 shows a sensor contact pad of the present disclosure connected to an analytical device via a clip and copper wire. [Figure 16] 1 illustrates one embodiment of a portable breath analysis device of the present disclosure. [Figure 17] 1 illustrates one embodiment of a filmed finger electrode for a gas sensor of the present disclosure. [Figure 18] 4 illustrates a manufacturing process for the interdigitated electrodes of the sensor of the present disclosure. [Figure 19] 19a-c show various possible electrode layouts for the sensors of the present disclosure. [Figure 20]1 shows both a PPY-DBSA sensor and a PANI-CSA sensor according to certain embodiments of the present disclosure. [Figure 21] 1 shows the effect of 5% CO 2 on PPY sensors doped with various dopants (i.e., PPY-ASA, PPY-HBSA, and PPY-DBSA). [Figure 22] 1 shows a PPY-ASA sensor and a PANI-CSA sensor according to certain embodiments of the present disclosure, and also shows the chemical structure of 3-aminobenzenesulfonic acid. [Diagram 23] 1 illustrates steps in an electrochemical polymerization technique according to certain embodiments of the present disclosure. [Figure 24] 1 shows another embodiment of a breath analyzer according to the present disclosure, comprising both a PPY-ASA sensor and a PANI-DNNSA sensor. [Diagram 25] Photographs showing electrochemical sensors prepared by SPANI / PEO blend solutions. [Figure 26] 1 is a graph showing electrical conductivity measurements of SPAN / PEO (30 wt %) upon exposure to carbon dioxide. [Figure 27] 1 is a graph showing the change in resistivity of various conductive polymers with respect to CO 2 . [Figure 28] 1 is a graph showing CO2 readings from a CO2 meter sensor. [Figure 29] FIG. 1 is a schematic perspective, partially cut-away view of a bench prototype of the present disclosure. [Diagram 30] 1 is a photograph showing a bench prototype of the present disclosure. [Diagram 31] 1 is a graph showing the results of a breath test using a CO2 meter. [Diagram 32] 1 is a photograph showing two CO2 sensors, including a PANI / ABSA sensor and a PPY / ABSA sensor. [Diagram 33] 1 is a graph showing the CO2 response of SPANI with 10 wt% PEO. [Diagram 34] 1 shows a non-limiting example of a wireless communication breath analysis device of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The following detailed description should be read with reference to the drawings, in which like elements in different drawings bear like reference numerals. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. Those skilled in the art will recognize that the examples provided herein have many useful alternatives that are within the scope of the invention.

[0015] Conductive polymers are widely used in gas sensor applications because they provide a stable porous matrix for gas components and also modify the electron transfer process. In recent years, many efforts have been made with the aim of improving the physical properties (e.g., solubility, dispersion properties, stability, and mechanical integrity) of conductive polymers. The formation of such complexes has been optimized to prepare materials that can be processed for the manufacture of sensors. Polyconjugated conductive polymer complexes have recently been used in gas sensing applications due to several useful features such as direct and easy deposition on the sensor electrodes, thickness control, and redox conductivity of the polyelectrolyte properties. The potential of these complexes, and the improved atmospheric stability of polypyrrole complexes, make them important candidates for use in certain technological applications. The advantages of applying conductive polymer complexes to gas sensors are their low cost, affinity to various substrates, high sensitivity, and processability.

[0016] Small amounts of NH3 and CO2 may be produced in exhaled air under circumstances unrelated to H. pylori infection, but baseline urea ( 13 C-labeled or unlabeled) as delta to pre-ingestion gas 13 The gases NH3 and CO2 (and / or 13 The simultaneous rise in CO2 suggests that the source of these gases is the urea produced by H. pylori. 13As described herein, the co-inventors of the present application have ensured that only the hydrolysis of NH3 and CO2 (and / or 13 NH3, CO2, and CO2) can be integrated into a portable handheld device that measures and provides instant test results. 13 We have identified and optimized polymer-based sensors that are highly sensitive to CO2. In many cases, these gases (NH3, CO2, and 13 The rise in urea (CO2) can be detected as early as 10 minutes and as late as 90 minutes after ingestion. Thus, an individual exhales into a current breath analyzer or collects an individual's breath sample, and the individual then measures the amount of urea ( 13 C-labeled or unlabeled) substrate must be harvested (i.e., collected) within 10-90 min (e.g., 20 min) of ingestion.

[0017] The present invention provides an improved breath analyzer and breath test method for determining the presence of H. pylori in the digestive tract of a subject, which is less expensive, more convenient, and more accurate in diagnosis than existing methods and devices.

[0018] As described in more detail below, innovative features of the breath analyzer (or breath analysis device) of the present invention include, but are not limited to: a) the detection of NH3, CO2, and 13 a) identification and optimization of a polymer-based sensor for simultaneous measurement of CO2; b) interfacing of signals from two sensors when a gas sample runs through both sensors simultaneously; c) interfacing of two independent sensors; d) software for simultaneously analyzing two or three different gas signals; and e) electronic circuitry and display of results. The display can show results that are either numeric or binary (e.g., positive, negative, etc.).

[0019] As described above, the novel breath analysis device of the present invention is capable of measuring NH3, CO2, and 13The breath analysis device contains two sensors, one sensitive to NH3 and the other sensitive to CO2 and 13 As used herein, CO2 is 12 CO2( 13 (not CO2). 12 CO2 and 13 The molecular weight of CO2 is very similar.

[0020] The term "simultaneously" refers to the simultaneous 13 Although used throughout this disclosure to refer to measuring the content of CO2, one skilled in the art will understand that such gas measurements do not need to be made at exactly the same time. Instead, in any or all embodiments of the present disclosure, the breath sample may contact each sensor of the present disclosure at the same time or nearly the same time. For example, the breath sample does not move to a first sensor and then to a second sensor when using the currently disclosed method and device. Rather, in certain embodiments of the present disclosure, the breath sample moves to both sensors through equidistant (but separate) channels from the mouthpiece to the sensor such that the breath sample reaches both sensors at the same time.

[0021] The urea breath test for detecting H. pylori is based on the ability that the bacterium (H. pylori) possesses to convert urea to NH3 and CO2. In one embodiment, the urea breath test ("UBT") of the present disclosure utilizes unlabeled urea as an exogenous substrate for H. pylori urease. This UBT method measures NH3 in the desired range of 25 ppb to 1 ppm, and CO2 (either alone or in combination) in the range of, for example, 14,000 to 28,000 ppm or 20,000 to 50,000 ppm. 13 (in combination with CO2) can be measured.

[0022] The UBT method and breath analyzer disclosed herein are capable of detecting the presence of urea ( 13 After ingestion of a substance (either C-labeled or unlabeled), the CO2 in that individual, 13In particular, the CO2 sensor of the present invention detects increases in CO2 and NH3 gas levels in breath samples from a baseline of 100 to 1000 pmp. 12 CO2 or 13 The breath testing method of the present invention is sensitive enough to detect an increase in the concentration of CO2 from a baseline breath sample. 13 If the subject exhibits such an increase in the concentration of CO2 or CO2, diagnosing the subject as having H. pylori. 13 None of the CO2 gases, by themselves, can be attributed solely to H. pylori hydrolysis of urea. For example, NH3 can be produced in renal and metabolic disease, while CO2 can be produced from muscle breakdown and colonic microorganisms. However, the co-inventors of the present application have discovered that the simultaneous rise in both gases (NH3, CO2) shortly after ingestion of unlabeled urea (e.g., within 10-90 minutes after ingestion) ensures that the source of the rise in both gases is H. pylori hydrolysis of urea. NH3, CO2, and / or CO2 after urea 13 CO2 values ​​are baseline NH3, CO2, and / or 13 If the UBT is higher than CO2 by a certain predetermined percentage, then the UBT is positive for H. pylori infection. 13 CO2 values ​​are baseline NH3, CO2, and / or 13 If it is the same as CO2 or lower than baseline, the UBT is negative for H. pylori infection.

[0023] In one embodiment, the procedure for the UBT of the present disclosure is as follows: a) the individual abstains from antibiotics, PPIs, bismuth, and sucralfate for two weeks (as they may inhibit H. pylori); b) prior to the UBT, the individual fasts for one hour (taking nothing by mouth); c) the individual exhales once into the input (e.g., mouthpiece) of the breath analyzer (no bag is required to collect breath), which is the baseline breath sample; d) the individual: 13Ingestion of a small solid or liquid meal (or capsule) containing either C-labeled or unlabeled (natural) urea; e) within 10–90 min after ingestion, the individual exhales one more time (no bag) into the input (e.g., mouthpiece) of the breath analyzer, which is the post-urea breath sample; f) Measurement of NH3, CO2, and / or 13 The result, calculated by the device's software as the difference between the post-urea and baseline values ​​of CO2 (i.e., post-urea minus baseline), is displayed on the breath analyzer display screen immediately after the second exhalation.

[0024] NH3 Sensor: First reported in 1862, polyaniline (PANI) is one of the most studied and widely used conductive polymers, in part because it is an inexpensive monomer, and also due to its facile synthesis in aqueous acidic solutions, environmental stability, good processability, and solubility in common organic solvents (thus enabling blending with other polymers).

[0025] Electrochemical Polymerization of Conductive Polymers: The following five paragraphs refer to an electrochemical process that can be used to develop a PANI sensor (such as the PANI sensor of the present disclosure), or any electrochemical sensor. This process is illustrated in FIG.

[0026] In general, the experimental setup for the electrochemical synthesis of conducting polymers in laboratory conditions is relatively simple. It often involves a standard three-electrode electrochemical cell, although a two-electrode cell can be used in the specific case of galvanostatic polymerization (Wallace et al., 2009). The polymer obtained in this procedure is deposited directly on the electrode. The anolyte and catholyte can be passed through the electrode compartment at a specified flow rate, while the polymerization can be achieved at a constant potential. The most common experimental techniques used for the electrochemical polymerization of aniline are the cyclic voltammetry (potentiodynamic), chronopotentiostatic, galvanostatic, and potentiostatic techniques.

[0027] Polymerization using chronopotentiometry is characterized by a periodic regular change of the electrode potential, and the deposited polymer is changed between a non-conducting and a conducting (doped) state throughout the experiment, followed by an exchange of electrolyte through the polymer (Heinze et al., 2010). At the end of the polymerization, the obtained polymer is in its non-conducting form. A relatively high potential is required for the electrochemical oxidation of the aniline monomer. Thus, for the first 2-10 cycles, the upper potential limit is high, but as a result of the autocatalytic nature of the aniline electropolymerization, the upper potential limit can be lowered to avoid degradation due to over-oxidation of the pernigraniline form of polyaniline (Inzelt, 2008).

[0028] The electrochemical polymerization of aniline proceeds with the insertion of chloride anions (dopant) from the electrolyte according to the following equation:

number

[0029] PANI exhibits three different oxidation states: leucoemeraldine (LEB, fully reduced), emeraldine (EB, semi-oxidized), and pernigraniline (PNB, fully oxidized). However, the protonated form of EB, the emeraldine salt, is the only conductive form and is usually obtained by protonating the basic amine and imine sites of EB with a strong acid. This is an important property of PANI, especially for detecting ammonia, because it deprotonates the amine groups in the emeraldine salt, converting it to the emeraldine base form with a corresponding decrease in conductivity of several orders of magnitude. This transition of polyaniline, from emeraldine salt (ES) to emeraldine base (EB), is shown in Figure 1. The reaction that allows this change in conductivity is as follows:

number

[0030] Camphorsulfonic acid (CSA) doped PANI has been shown to have a pH sensitivity of about 70 mV, which is comparable to other small counter ions (Cl - and SO4 2- This is the basis for choosing CSA over other protonic acids for the PANI ammonia sensor.

[0031] PANI is characterized by flexible chains, redoping ability, and high dispersibility in many organic or aqueous solvents (depending on the dopant). In particular, sulfonated polyaniline, which will be described in more detail below, has high sensitivity to carbon dioxide, high stability, and excellent electrical conductivity.

[0032] Fabrication of NH3 sensor: A non-limiting embodiment of the NH3 sensor of the present disclosure is shown in FIG. 2. To fabricate such a sensor, the following steps were carried out: HCl-doped PANI was prepared by chemical oxidative polymerization of aniline in aqueous acidic medium (1M HCl) using ammonium persulfate (APS) as the oxidizing agent. It has been previously reported that a higher polymerization yield can be obtained by using an oxidizing agent to monomer ratio of 1.2. The mixture was polymerized overnight at room temperature. The PANI precipitate was collected on a filter paper and repeatedly washed with 0.1M HCl and then with acetone. The resulting PANI salt was deprotonated by stirring the powder in 0.1M NH4OH aqueous solution at room temperature for 24 hours, thereby obtaining emeraldine base (EB), which was repeatedly washed with water until it reached a neutral pH and then dried in vacuum at 60° C. for 48 hours. PANI was redoped with CSA in a molar ratio of 2:1. Thin film interdigitated platinum electrodes (IDA) (100 μm row spacing) were purchased from the Electronic Design Center, Case Western University. Films were prepared by spin-coating the PANI-CSA solution onto the IDA electrodes. Prior to spin-coating, the electrodes were cleaned by rinsing with methanol, followed by deionized water, and drying in a dry nitrogen stream. A PANI film was then spin-cast onto the IDA (Figure 2).

[0033] NH3 Sensor Characterization: Calibration (Figures 3 and 4) was performed by first serially diluting 25 ppm ammonia to 2.5 ppm, 250 ppb, and 25 ppb; i.e., 10x dilution in a Tedlar bag. A 20 cc syringe was used to collect the sample from the Tedlar bag and inject the sample directly onto the sensor. The DropSens flow cell setup (Figure 5) was used to inject ammonia gas into the sensor, which was placed in the center of the DropSens flow cell. Teflon tubing was used to connect the gas to the flow setup to minimize any NH3 absorption.

[0034] Measurements were performed by applying a fixed potential of 1 V to the sensor (contact pads) and measuring the resulting current that changed with gas passing over the sensor surface (Figures 3 and 4). An Agilent 4155C semiconductor analyzer was used for the measurements, and customized test software was developed using the EasyDesktop software provided with the analyzer. Similar changes in conductivity and current were observed when using a Model 1010 gas diluter. A Model 660D potentiostat analyzer (CH Instrument, Austin, TX) was used to measure the resistivity of the sensor. The observed changes in resistivity at 250 ppb and 25 ppb were approximately 4.8% and 2.5%, respectively, which are high enough to reliably analyze breath samples at trace levels of ppb.

[0035] Sensitivity of the NH3 sensor of the present disclosure: Human breath contains trace amounts of CO2, N2, O2, NH3, NO, H2O, methane, volatile organic compounds (VOCs), and other gases. To evaluate the effect of 4-5% concentration of breath CO2 on the PANI-CSA sensor, the co-inventors of this application tested various CO2 concentrations. The effect at 4-5% CO2 concentration is negligible and cannot be measured, as shown in Figure 6. The overall sensitivity of the PANI-CSA sensor to NH3, CO2, N2, and air is shown in Figure 7. PANI-CSA showed a much higher response to NH3 compared to CO2, N2, and air, considering that the concentration of NH3 was 25 ppm (0.000025%), while 100% dry gas was used for CO2 and N2 (human breath contains 4-5% CO2 and trace amounts of N2).

[0036] 13 C is the naturally occurring isotope of carbon and is encountered in nature at a concentration of 1.8% of the total carbon. 13 Increase in CO2 concentration causes H. pylori urea ( 13 The possibility that the product is other than the hydrolysis of C-labeled urea is negligible. The polymer-based CO2 sensor of the present disclosure also 13 Highly sensitive to CO2,13 The present invention can detect both CO2, CO2, and CO2, either individually or cumulatively. 13 C-labeled urea or 13 Either C-labeled urea or C-unlabeled urea can be used to detect H. pylori after ingestion.

[0037] CO2 Sensor: Many studies on CO2 gas sensing have been reported using doped or undoped SnO2. For CO2 gas sensing, less attention has been paid to electrically conductive polymers such as polypyrrole, which have unique properties such as low density, versatility in methods of production, high anisotropy of electrical conduction, and non-metallic temperature dependence of conductivity. Polypyrrole (PPY) can be prepared by various methods such as chemical, electrochemical, and gas-phase routes.

[0038] It has been reported that when polypyrrole, a type of organic polymer, is oxidized, it becomes a conductive polymer. The co-inventors of the present invention tested the response of doped polypyrrole to 5% CO2 (Figure 21). When polypyrrole was doped with 3-aminobenzenesulfonic acid (ASA), the effect of CO2 was significantly higher than when polypyrrole was doped with 4-hydroxybenzenesulfonic acid (HBSA) or 4-dodecylbenzenesulfonic acid (DBSA), making PPY-ASA more responsive to CO2 than either PPY-DBSA or PPY-HBSA.

[0039] Fabrication of CO2 sensor: In one embodiment of the present disclosure, a CO2 sensor, particularly a PPY-based sensor, was fabricated using dodecylbenzenesulfonic acid (DBSA) as a dopant (Figure 8). Pyrrole (Aldrich) was dried over CaH2 for 24 hours and then distilled under reduced pressure. Ammonium persulfate (APS, Kanto Chemical Co. Inc.) was used as the oxidant and dodecylbenzenesulfonic acid (DBSA, Aldrich) was used as the dopant. 0.15 moles of DBSA and 0.3 moles of pyrrole were dissolved in 500 ml of distilled water under vigorous stirring. 0.06 moles of APS in 100 ml of distilled water was slowly added to the above solution maintained at a temperature of 0°C. The obtained PPY powder (1 g) was completely dissolved by sonication in 25 ml of chloroform containing 25 ml of m-cresol alone or additionally 1 g of DBSA, and then filtered through a 1 μm Teflon membrane filter. The solution was transferred to an interdigitated platinum finger electrode (Case Western University) with gold circuitry, and the solvent was dried to obtain a free-standing film of excellent quality with a thickness of about 100 μm. FT-IR was used to characterize the characteristic peaks of dopant and pyrrole. A smooth and coherent film was obtained by the above preparation and cast onto an additional wafer surface for examination under a scanning electron microscope (SEM).

[0040] Resistivity of CO2 Sensor: The PPY-DBSA sensor of the present disclosure was characterized using a DropSens flow cell setup (Figure 5). The change in current (resistivity) of the PPY-DBSA sensor upon exposure to 5% CO2 (Figure 9) was measured using a Model 660D potentiostat analyzer (CH Instrument, Austin, TX) using amperometric it technology. The PPY-DBSA sensor was tested for sensitivity to CO2, O2, H2O, and air.

[0041] Calibration of CO2 sensor: The PPY-DBSA sensor of the present invention was calibrated using 100% dry gas. A PrecisionGas Diluter Model 1010 from Custom Sensor Solutions was used to deliver the analytical gas (CO2) into the sensor in the center of the DropSens flow cell. A mass and volume flow meter with ±0.8% accuracy (Omega Engineering, Inc., Norwalk, CT) was connected to record the flow rate. The change in resistivity changed with the change in CO2 concentration (Figure 10). The CO2 sensor was tested for response to O2, N2, H2O, and air (Figure 11). The effect of air is negligible and the effect of 100% O2 gas is minimal. However, H2O has a larger response to the resistivity of the CO2 sensor.

[0042] Both sensors of the present invention (CO2 and NH3) require optimization, as described in more detail below.

[0043] NH3 Sensor Optimization: The co-inventors of this application developed a setup to fabricate a PANI-CSA sensor and characterized it. Published reports showed that patients testing positive for H. pylori infection have baseline NH3 breath concentrations in the range of 0.02-0.17 ppm and increased NH3 concentrations in breath after ingestion of unlabeled urea in the range of 0.05-1 ppm.

[0044] Effects of CO2, N2, O2, and H2O: To further optimize the PANI-CSA sensor, the PANI-CSA sensor is exposed to conditions similar to those occurring in human breath. Human breath primarily contains CO2, N2, O2, and H2O. Based on preliminary data from the co-inventors of the present invention, the sensor response to 100% CO2 and 100% N2 is minimal, and the response to air is negligible. Because human breath contains well below 100% CO2 and N2, interference from CO2 and N2 in breath is negligible and therefore insignificant.

[0045] Humidity effects on NH3 sensor: NH3 is hydrophilic and the humidity of human breath can interfere with the sensor response to NH3. To address the humidity effects, a desiccant is used and titrated using a VTIRH-200 relative humidity generator.

[0046] Optimization of the CO2 sensor: The co-inventors of this application have developed a setup to fabricate a highly sensitive PPY-DBSA sensor for CO2. 13 Based on published reports on C UBT, patients infected with H. pylori 13 C-labeled urea was also elevated in the breath after ingestion. 13 With CO2 and above the CO2 baseline 13 The rate of increase in exhaled CO2 ranges from 2.4% to 4.4%, depending on the amount of urea available. Based on these findings, the co-inventors of the present application have determined that the rate of increase in CO2 above baseline following ingestion of 150-300 mg of unlabeled urea is: 13 After ingestion of C-labeled urea 13 We believe this is similar to the rate of increase in CO2.

[0047] Based on the sensor calibration (FIG. 10), it is believed that the CO2 sensor of the present disclosure can sense even below the lowest rate of CO2 rise in patients infected with H. pylori. Although PPY-DBSA has not been reported to be sensitive to NH3, the co-inventors of this application will investigate whether the sensor is sensitive to NH3 and, if so, place an NH3 specific filter (e.g., 3A foam crystalline metal aluminosilicate) directly above the CO2 sensor to block NH3 from contacting the CO2 sensor. This filter, which is a desiccant, blocks both NH3 and H2O.

[0048] Effects of CO2, O2, H2O, air and NH3 on CO2 sensor: The co-inventors of the present application have tested an embodiment of the CO2 sensor of the present disclosure for response to CO2, O2, H2O and air (FIG. 11). Since the effect of air is negligible, O2 and N2 in human breath are believed to have only a minor effect, if any, on the CO2 sensor. Because the content of O2 and N2 in human breath is far less than 100% of the gases tested by the co-inventors of the present invention. Further testing of the effects of O2 and N2 on the CO2 sensor is not believed to be necessary.

[0049] Effect of humidity on CO2 sensors: Preliminary data from the co-inventors of the present invention indicates that humidity affects the resistivity of the PPY-DBSA CO2 sensors of the present invention (Figure 11). To counter this effect, a desiccant can be used and the amount of desiccant can be titrated by using different amounts and examining their effect on the resistivity of the CO2 sensor in the presence of the desiccant.

[0050] The VTI RH-200 Relative Humidity Generator can be used to generate various levels of relative humidity (RH) and to generate CO2 and / or 13 It is possible to calculate the amount of desiccant required for the optimum level of RH to achieve optimal sensitivity (resistivity change) to CO2.

[0051] One embodiment of the portable, handheld breath analysis device of the present invention is shown in Figure 15. As described above, the device measures NH3 and CO2 (and / or 13 In a bench prototype of the device of the present invention, the co-inventors of this application will connect both sensors (e.g., PANI-CSA and PPY-DBSA or SPANI), standardize the prototype for both gases (CO2 and NH3), and optimize the prototype for eventual use with breath samples from patients with H. pylori.

[0052] Non-limiting embodiments of bench prototype: In one embodiment of the present disclosure, the manufactured and optimized PANI-CSA and PPY-DBSA sensors can be used to set up a bench prototype as shown in FIG. 12. Two DropSens flow cells can be used, including DropSens1 for the PPY-DBSA sensor measuring CO2 and DropSens2 for the PANI-CSA sensor measuring NH3. In another embodiment of the bench prototype, the DropSens flow cell is eliminated and the bench prototype configuration does not include a flow cell. In this embodiment, the sensors are directly connected to a CH instrument for gas analysis.

[0053] The two DropSens flow cells are connected to a gas flow two-way valve 5 via tubes 1, 2, 3, 4. Photographs and schematic diagrams of the two-way valve are shown in Fig. 13 and Fig. 14, respectively. Humidity filters and / or desiccants are placed in tubes 1 and 2 in a configuration (circular, spiral, etc.) that optimizes the flow of the gas mixture to each DropSens. Pressure gauges are attached to tubes 1 and 2. The pressure gauges adjust the flow of gas (or exhaled breath) in each tube (1, 2), so that the flow of gas to each sensor (DropSens1 and DropSens2) is the same in the presence of desiccant in each tube. Those skilled in the art will understand that desiccant may change the flow of gas through the tubes, which in turn can be adjusted using the pressure gauges in tubes 1, 2.

[0054] Gas flow two-way valves are used during optimization of the bench prototype to divert the gas mixture to each side of the device. The analysis gas is pretreated to remove water, suspended particles, or unwanted gases before being characterized by each gas sensor. In the case of two gas sensors, as in the bench prototype of Figure 12, the main gas stream is split into two separate gas streams for pretreatment by the diversion valve (e.g., as shown in Figures 12 and 13). The flow ratio of the two outlet streams can be adjusted by opening either or both of the pressure gauges.

[0055] The diversion to one or the other sensor is only for the purpose of individual characterization and calibration of each sensor. Finally, a gas mixture containing NH3 and CO2 goes to both sensors and the valves are opened in both directions. Each sensor receives the same gas mixture as if an individual were to breathe into the device. The same exhaled air is then sent to each sensor. This explains why the NH3 sensor is manufactured so that CO2 does not affect it, and why the CO2 sensor is manufactured so that NH3 does not affect it (and a desiccant that blocks NH3 is placed directly above it). The co-inventors of the present invention have demonstrated from the experiments described herein that the remaining elements of the exhaled air (except CO2 and NH3) do not affect either sensor.

[0056] Measurement of NH3 and CO2: In the proposed bench setup (Figure 12), the sensor measures the gas mixture (NH3, CO2, and / or 13 The contact pads of the sensor (Fig. 2, Fig. 5) are connected to the analyzer via clips and copper wires (Fig. 15). The co-inventors of the present invention use an Agilent 4155C semiconductor analyzer and customized test software developed using the EasyDesktop software provided with the analyzer. NH3 and CO2 (and / or 13 Measurements of two or more gases, including CO2, are obtained by applying a fixed potential of 1V to the sensor for 200 seconds and measuring the change in current that occurs in response to the gas passing over the surface of the sensor.

[0057] CO2 sensor CO2 (and 13 Approaches to improve CO2 affinity:

[0058] Method 1 for fabricating CO2 sensor: Amine modification of PPY Amine modification of sorbents is frequently used to introduce CO2-philic functionality. In principle, the nitrile groups of PPY can be reduced to primary amines using a variety of reagents. However, reactions that work well with low molar mass compounds are not always effective when applied to high molar mass polymers.

[0059] Polypyrrole-based polymers (PPY) have been used to detect CO2 because aromatic amines are the focus of certain chemical interactions. PPY exhibits high conductivity and sensitivity to CO2, but it is very difficult to work with (e.g., due to its inflexible backbone and low solubility) and has poor stability properties. This is mainly because the aromatic five-membered rings are covalently linked to each other and have very limited rotational freedom and low solubility, especially in the doped state. Polythiophenes are also five-membered rings and have similar problems. In the 1990s, there were attempts to solve the problem by alkylating thiophene monomers. The polymers became soluble and processable in the undoped state and attracted a lot of attention. However, after doping, the rigidity of each aromatic unit limited the solubility regardless of the alkyl group. Those skilled in the art will understand that chemical modification is a complex synthetic process and that dispersants reduce the accuracy of the process.

[0060] Increasing the amine content, thereby increasing the CO2 (and 13 To improve the CO2 affinity, the co-inventors of the present invention used diaminonaphthalenesulfonic acid (DANSA) as a dopant. The incorporation of a primary amine improves the CO2 affinity compared to the parent polymer, as demonstrated by the co-inventors' gas adsorption experiments on membrane samples coated on electrodes and by gas property studies of the membrane sensor.

[0061] Another method for fabricating a CO2 sensor is to polymerize PANI and oxidize it with 3-aminobenzenesulfonic acid. PANI is a more stable polymer than polypyrrole (PPY), and doping PANI with 3-aminobenzenesulfonic acid (ASA) produces a sensor with a much higher response to CO2 than a PPY-ASA sensor.

[0062] Method 2 for fabricating a CO2 sensor using sulfonated polyaniline (SPANI) The desired polyaniline is sulfonated polyaniline ("SPANI"), which is self-doped since sulfonic acid groups are covalently linked in the polyaniline backbone. SPANI is also water-soluble since the additional sulfonic acid groups result in water solubility (which works for gas sensing but creates problems in aqueous use). Water-soluble poly[bis(4-phosphonic acid)phenoxy]phosphazene (PPAP) can be selected, which can be a good candidate as a doping agent for PANI. Freshly prepared and dried acid-functional aryloxypolyphosphazene (PPAP) was dissolved in 10 mL of water at 0-5 °C in a round-bottom 100 mL flask, and aniline monomer was added by vigorous stirring (ANI:PPAP ratio 2:1). Then, ammonium persulfate aqueous solution (aniline / oxidant ratio 1:1) was slowly added to the reaction mixture as an oxidant. The reaction turned green in 1 hour and was allowed to stir overnight. The dark green solution obtained from the dialysis membrane was transferred to a Teflon Petri dish and dried overnight in a vacuum oven at 50° C. to produce SPANI, which was confirmed by FTIR and P-NMR.

[0063] Method 3 for fabricating CO2 sensor using water-soluble sulfonated polyaniline (SPANI) For SPANI synthesis, emeraldine hydrochloride PANI polymer powder (1 g) was dispersed in 150 ml of dichloroethane (DCE) at 80°C. Chlorosulfonic acid (1.2 ml) diluted with 15 ml of 2 equivalents of DCE (i.e. 15 ml + 15 ml) was prepared and added to the dispersion solution for 30 min and stirred for 5 h. When the first 15 ml was exhausted, the second 15 ml could be used until the reaction time was 30 min in total. The solid product was then collected by filtration, carefully washed twice with cold water, immersed in 200 ml of distilled water, and heated at 100°C for 4 h to hydrolyze. After hydrolysis, the green solution was dried by vacuum evaporation at 40°C. The crude SPANI powder was collected and washed with methanol to remove impurities, then filtered and dried in an oven at 40°C.

[0064] Alternatively, an aqueous solution of SPANI can be prepared by dissolving SPANI in water. The structure can be confirmed by P-NMR and the concentration of SPANI in the aqueous solution can be measured by UV-Vis spectroscopy. Other solvents (i.e., other than DCE and water) can be used to dissolve SPANI as long as the solvent can dissolve PANI and the acid.

[0065] Sulfonated polyaniline (especially when prepared by method 3 above) exhibits good solubility in water. However, the poor volatility and hydrophobicity of the finger electrodes are a result of poor adhesion between the electrodes and the polymer. To address these issues and increase the adhesion of the films, polyethylene glycol ("PEG") or polyethene oxide ("PEO") have been used as catalysts due to their low glass transition temperatures (T g ) and was used as a binder due to its hydrophilicity.

[0066] Alternative methods to enhance the adhesion of the film may include electrochemical polymerization or using PPY / ABSA film (4-acetamidobenzenesulfonyl azide) (i.e., polypyrrole doped with ABSA). Two exemplary CO2 sensors are shown in FIG. 32, including a PPY / ABSA sensor and a PANI / ABSA sensor (i.e., polyaniline doped with ABSA). Applicants have found that the electrical conductivity of the PANI / ABSA sensor is low (about E-12).

[0067] As shown in Figure 25, three different mass ratios (10 wt%, 20 wt%, and 30 wt%) of PEO were blended with SPANI and drop cast onto finger electrodes. However, for the low ratio of PEO (10 wt%), almost no phase separation was observed. However, for the high ratio of PEO (30 wt%), the film has a uniform and single-phase appearance. The baseline conductivity in air was 60 ± 5 μA at 0.5 V.

[0068] Conductivity measurements were performed with a CH Instrument by applying 0.5 V and measuring the emerging current. As shown in Figure 26, the baseline (air) shows stable values ​​and low noise. The current change with 5% CO2 is shown, and the baseline can be recovered very quickly when purging with air.

[0069] Four different conducting polymer electrochemical sensors were prepared and tested for their response to CO2. The conducting polymers tested included PPY / ASA; PPY / HBSA; PPY / DBSA; and SPANI. The test gas was 5% carbon dioxide. The SPANI sensor was tested and the resistance change rate was 40% after exposure to carbon dioxide. The results are shown in Figure 27 and demonstrate that SPANI has high potential in CO2 sensing applications.

[0070] Figure 28 is a graph showing CO2 measurements from a CO2 meter sensor. The operating range of the CO2 meter is less than 5% and the sensitivity is approximately 100 ppm.

[0071] 29 and 30 show a bench prototype. As shown in FIG. 29, the prototype has dual channels for characterization of CO2 and NH3 gas. In particular, the prototype includes an NH3 sensor, an NH3 channel, a CO2 channel, a CO2 meter, and a temperature and humidity sensor. The ammonia and CO2 channels are configured to receive breath samples through a tube (not shown) that serves as a mouthpiece. As shown in FIG. 30, the location of the NH3 sensor refers to the space where the ammonia sensor is placed in the prototype. Those skilled in the art will understand that the location of the ammonia sensor may be different from that shown in FIG. 30. The CO2 meter of the bench prototype is an industrial type CO2 sensor (ExplorIR-M 5% CO2 sensor) that was used in the study of the prototype device.

[0072] The bench prototype also includes humidity and temperature sensors, one possible location of which is shown in FIG. 30. In most cases, the temperature and humidity sensors will indicate that the temperature is room temperature (e.g., about 70 degrees Fahrenheit). The humidity is expected to be different for the NH3 and CO2 sensors. This is because the humidity of the breath is blocked in most cases by about 80-90% of the NH3 sensor (e.g., by using a desiccant). In some embodiments, a desiccant will be used in the CO2 channel to block some of the humidity of the breath sample before it reaches the CO2 sensor.

[0073] Figure 31 is a graph showing the results of a breath test using a CO2 meter. As shown, the CO2 meter signal becomes saturated with exhaled air and has an operating range of 0-5% CO2.

[0074] 33 is a graph showing the CO2 response of SPANI using 10 wt% PEO. As shown, the noise was significantly reduced (compared to PANI / ABSA) with the SPANI-PEO (10%) sensor, and the change in current (I%) at 1% CO2 was 13%.

[0075] Conductivity measurements and the closely related salinity measurements are important in multiple applications from characterization and sensing of specific gases. A typical layout of finger electrodes in the area of ​​a gas sensor is shown in Figure 17. Extensive research has been done on the measurement of H2, O2, NO x , CO, etc. Additionally, materials and circuit layouts have been found to improve the performance of these specific gas applications. Various metallic materials (gold, silver, platinum, etc.) deposited on top of the dielectric substrate can provide the desired working potential and interface properties.

[0076] Conductive materials are coated onto the electrodes of the present disclosure to complete the galvanic circuit for characterizing the flow of electrons. Conductive polymers, such as polyaniline, are the interactive films of the gas sensors of the present invention. The attachment of gas molecules with different affinities changes the electrical properties of the film, which is reflected in the current measurement. The layout of the electrodes has also been reported to affect the performance of the galvanic characterization. A number of alternative layouts that have been prepared for the gas analysis device are shown in the figures.

[0077] Fabrication of electrodes for gas characterization: A planar micro-supercapacitor configuration can be chosen, where the interdigitated electrodes are fabricated on the same plane and isolated by physical separation. This configuration has the advantage of being easy to fabricate and flexible depending on the choice of electrodes. Figure 18 shows a non-limiting example of the fabrication procedure of the sensor of this device. The patterned electrodes are fabricated by three main steps: deposition, patterning, and pyrolysis of photoresist. A 5 mm thick alumina nitrile substrate is used to electrically insulate the supercapacitor from the substrate. SU-8 photoresist (MicroChem) is spun coated on the substrate to a thickness of about 10-100 μm. After soft baking at 115 °C for 5 min in air, the interdigitated electrodes are patterned by UV lithography. The chip is exposed to a plasma PVD treatment of gold, silver, or platinum under Ar (argon) and then transferred to a sputter coating device. The current collector was then deposited using evaporation of a 100 nm Ti / 400 nm Au layer, annealed at 250 °C for 20 min, and patterned by a conventional lift-off process to remove the photoresist and blocked metal.

[0078] The electrodes used in any of the sensors of this disclosure may include interdigitated platinum, gold, or silver lines printed thick film on a 0.6 mm thick alumina substrate, which provides excellent adhesion with the printed lines. Such electrodes are used by spreading the material over the interdigitated fingers. Bonding pads allow the lines to be contacted for electrical connection.

[0079] Electrode Layout: The circuit layout determines the performance and consistency of the conductivity measurement. Several circuit layouts for interdigitated electrodes are described below and shown in Figures 19a-19c. Any of these electrode layouts can be used in any (or all) sensors of the present invention.

[0080] The electrodes may have a single channel or a multi-channel arrangement. One possible electrode design is a finger electrode, as shown in FIG. 19a. The gap between the electrodes determines the overall current flow rate at the desired value of 1 μA. Another electrode layout (as shown in FIG. 19b) includes two elongated lines formed into a rectangular configuration. Yet another electrode layout (as shown in FIG. 19c) includes two lines elongated into a spiral configuration. Alternative electrode configurations are also contemplated and are within the scope of the present disclosure.

[0081] In another embodiment of the present invention, NH3 and CO2 or 13 Each CO2 sensor is placed in its own sealed chamber within the device. In this embodiment, a breath sample is introduced into the device through a mouthpiece, and each sensor receives a portion of the same breath sample. The sealed chamber of each sensor receives NH3, CO2 or 13 This allows for the placement of filters and / or desiccants that block specific gases directly in close proximity to each sensor without affecting the response of other sensors to the same exhaled content of CO2.

[0082] In some embodiments, the breath analysis device can connect to and communicate with remote devices (such as smartphones, wireless hubs, computers, or servers in the cloud) using one or more communication technologies, including but not limited to wired communication (such as USB), wireless and cellular communication (such as WiFi, Bluetooth, ZigBee, GSM, LTE, and infrared). Data can be transmitted as plain text or after encryption.

[0083] Figure 34 shows a non-limiting example of a wireless communication breath detection device. A breath sample is exhaled into the mouthpiece of the breath analysis device and processed by the breath analysis device. The results are then filed or transmitted to a computer, one or more smart devices, or the cloud.

[0084] In some embodiments of the breath analysis device, the data communicated from the breath analysis device includes data of direct measurement of gas concentration, and device health information such as device temperature and battery status. The data communicated from the breath analysis device may be raw data read directly from the sensor(s), or may be data processed in the breath analysis device after signal conditioning. The communicated data may also be derived data such as the patient's health status, the status of a disease the patient has, or health data.

[0085] In some embodiments of the breath analysis device, data communicated to the breath analysis device from a smartphone, wireless hub, computer, or a server in the cloud may include device software updates, device parameter updates, and information about the user or the user's health, health or disease status.

[0086] Although several preferred embodiments of the present invention have been described, it should be understood that various changes, adaptations and modifications can be made therein without departing from the spirit of the invention and the scope of the appended claims.

Claims

1. an input for receiving a breath sample; a first sensor in contact with the breath sample, the first sensor including a first conductive polymer and a conductive material, the first conductive polymer in contact with the conductive material, the first conductive polymer having a resistivity that increases in response to increased ammonia concentration; A second sensor in contact with the breath sample, the second sensor comprising a second conductive polymer and a conductive material, the second conductive polymer contacting the conductive material of the second sensor, the second conductive polymer being amplified. １２ CO ２ and １３ CO ２ a second sensor having a resistivity that increases in response to a concentration of said second conductive polymer, said second conductive polymer comprising sulfonated polyaniline blended with polyethylene oxide; and A processor; an electrical circuit operatively connecting the first sensor and the second sensor to the processor, the processor detecting resistivity of the first sensor and the second sensor and using the resistivity to determine a total concentration of ammonia in the breath sample and １２ CO ２ and １３ CO ２ An electrical circuit for calculating the total concentration of A breath analyzer comprising:

2. 2. The breath analyzer according to claim 1, wherein the sulfonated polyaniline is synthesized from the emeraldine form of polyaniline polymer.

3. 3. The breath analyzer according to claim 1 or 2, wherein the conductive material of the first sensor and / or the second sensor comprises a plurality of electrodes.

4. The breath analyzer according to any one of claims 1 to 3, wherein the breath analyzer is in wireless communication with a remote device.

5. The breath analyzer of any one of claims 1 to 3, wherein the breath analyzer has two separate channels and the breath sample is configured to travel from the input through the separate channels to each of the first sensor and the second sensor.

6. 4. The exhalation device according to claim 1, wherein the ratio of polyethylene oxide to sulfonated polyaniline is between 10% and 30% by weight.

7. 7. The breath analyzer according to claim 6, wherein the ratio of polyethylene oxide to sulfonated polyaniline is 30% by weight.

8. 1. A method for detecting H. pylori in the gastrointestinal tract of a subject, comprising: Collecting a baseline breath sample from the subject using a breath analyzer according to any one of claims 1 to 7; The breath analyzer is used to determine the concentration of ammonia present in the baseline breath sample, and １２ CO ２ and １３ CO ２ determining the concentration of A predetermined amount of １３ ingesting a meal containing C-labeled or unlabeled urea; collecting a post-urea breath sample from the subject using the breath analyzer; The breath analyzer was used to measure the concentration of ammonia present in the breath sample after ingestion of the urea, and １２ CO ２ and １３ CO ２ determining the concentration of said concentration of ammonia present in said breath sample after ingestion of said urea; and １２ CO ２ and １３ CO ２ the concentration of ammonia present in the baseline breath sample and １２ CO ２ and １３ CO ２ indicating the presence of H. pylori in the gastrointestinal tract of the subject if the concentration exceeds A method comprising:

9. said concentration of ammonia present in said breath sample after ingestion of said urea; and １２ CO ２ and １３ CO ２ the concentration of ammonia present in the baseline breath sample and １２ CO ２ and １３ CO ２ 9. The method of claim 8, further comprising indicating the absence of H. pylori in the gastrointestinal tract of the subject if the concentration does not exceed 100%.

10. The method according to claim 8 or claim 9, wherein collecting the baseline breath sample from the subject and collecting the post-urea ingestion breath sample from the subject comprises collecting both the baseline breath sample and the post-urea ingestion breath sample from a single subject and from a single portable breath analyzer, the single portable breath analyzer being a breath analyzer according to any one of claims 1 to 7.

11. A breath testing method comprising: (a) providing a breath analysis device according to any one of claims 1 to 7; (b) prompting the subject to exhale a baseline breath sample into the breath analyzer; (c) the processor measuring a resistivity of the first sensor that occurs when the baseline breath sample contacts the first sensor; (d) the processor measuring a resistivity of the second sensor that occurs when the baseline breath sample contacts the second sensor; (e) providing the subject with a meal or capsules containing urea, the urea comprising: １３ either C labeled or unlabeled; (f) prompting the subject to exhale a post-urea breath sample into the breath analyzer; (g) the processor measuring a resistivity of the first sensor that occurs when the post-urea breath sample contacts the first sensor; (h) the processor measuring a resistivity of the second sensor that occurs when the post-urea breath sample contacts the second sensor; (i) comparing the measured resistivity of the baseline breath sample to the measured resistivity of the post-urea breath sample; (j) calculating a difference between the measured resistivity of the first sensor of the baseline breath sample and the measured resistivity of the first sensor of the post-urea breath sample by calculating the measured resistivity of the first sensor of the baseline breath sample minus the resistivity of the first sensor of the post-urea breath sample; (k) calculating a difference between the measured resistivity of the second sensor of the baseline breath sample and the measured resistivity of the second sensor of the post-urea breath sample by calculating the measured resistivity of the second sensor of the baseline breath sample minus the resistivity of the second sensor of the post-urea breath sample; (l) NH ３ said difference in resistivity of said first sensor in ppb and CO ２ and １３ CO ２ expressing the difference in resistivity of the second sensor in ppm; (m) indicating a final result as positive for H. pylori if the difference between the resistivity measured after urea ingestion and the resistivity measured at baseline of the first and second sensors is a positive number and as negative for H. pylori if the difference between the resistivity measured after urea ingestion and the baseline of the first and second sensors is zero or a negative number; A method comprising:

12. The breath testing method according to claim 11, wherein the urea is unlabeled urea.

13. The breath test method according to claim 11 or 12, wherein the subject exhales the post-urea breath sample into the breath analyzer within 10 to 90 minutes after taking a meal or a capsule.

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