GB2600990A

GB2600990A - Rapid non-invasive testing for disease using clothing

Info

Publication number: GB2600990A
Application number: GB2018014.7A
Authority: GB
Inventors: Stanley Curtis Mervyn
Original assignee: Roboscientific Ltd
Current assignee: Roboscientific Ltd
Priority date: 2020-11-16
Filing date: 2020-11-16
Publication date: 2022-05-18
Also published as: GB202018014D0

Abstract

An apparatus for detecting a viral or bacterial disease from volatile organic compounds (VOCs) absorbed onto a facemask 2 from the breath of a subject. The apparatus comprises: (a) a housing into which the facemask can be inserted and also containing a heater 3 whose temperature can be controlled between 30 and 90 degrees Celsius; (b) an air sampling unit able to take a sample of the odours or VOCs emitted by the face mask heated inside the container and to divert the sample to enter a sensor set 9, which comprises at least two sensors for sensing VOCs; (c) a processing unit 10 comprising a pattern recognition analyser for comparing an output signal of the sensor set to disease-specific patterns derived from a database; and (d) a housing. The apparatus may alternatively use VOCs from the sweat of a previously worn piece of clothing.

Description

Intellectual Property Office Application No G1320180147 RTM Date:8 October 2021 The following terms are registered trade marks and should be read as such wherever they occur in this document: Tenax C arbotrap Carbopack C arb oxen Intellectual Property Office is an operating name of the Patent Office www.gov.uk/ipo Rapid Non-Invasive Testing for Disease using clothing

BACKGROUND AND SUMMARY OF THE INVENTION

There are many methods of testing a subject for infection by a particular disease. These are largely based upon PCR or Elisa type of technology which are invasive requiring typically a swab taken from the gums or from the nasal area and usually they are undertaken by trained personnel. Such tests are expensive for large-scale testing particularly when conducted regularly. Thus there is a need for a testing method that is inexpensive to use; is non-invasive and less intrusive and which can give a result in seconds. Such a system would permit the pre-screening of large numbers of subjects for disease, allowing rapid interventions or further targeted laboratory based testing.

The present invention relates to a non-invasive sampling, sensing and detector system which will detect viral & bacterial diseases causing illness in human subjects, by measuring and analysing and making comparison with the digital fingerprints of mixtures of odours or Volatile Organic Compounds in the breath or body sweat of the subject.

It is well known that certain volatile compounds can be detected on the breath and that such volatiles can be indicative of certain diseases or conditions. By way of example, it is recognised that the smell of acetone on the breath is indicative of ketosis, and that this can be related to diabetes mellitus. It is also well known that alcohol on the breath is indicative of blood alcohol levels. The technique of detecting diseases by measuring and analysing and making comparison with the digital fingerprints of mixtures of odours or Volatile Organic Compounds is well established in the prior art with several inventions using breath samples from subjects.

Examples of this prior art include Neel (1994) U.S. Pat. No. 5,356,594, Satterfield (2014) U.S. Pat. Application US 2014/0276100 Al, Philips (2001) U.S. Pat. No. 6,312,390, Philips (2001) U.S. Pat. No. 6,221,026, Sood (2014) U.S. Pat. Application US 2014/0127326 Al and Wang (2004) U.S Pat. Application US 2004/0137637 Al.

The present invention does not require a breath or body sweat sample to be taken directly from the subject. Instead the testing sample is the face mask of a type commonly and routinely worn as protection during an outbreak of contagious disease or a pandemic. After use the mask is placed in a container attached to a VOC sampler and analyser. The sample is heated to a temperature between 30 and 90 degrees Celsius which action releases the odours or Volatile Organic Compounds which have been absorbed into the mask's material from the subject's breath during the time the mask was worn. Similarly the sample could be a piece of clothing such as a sock which would have absorbed body sweat during the period when it was worn. It could also be placed into the container and heated to release the odours or Volatile Organic Compounds for sampling and measurement.

The base system comprises: (a) a container for holding the used mask or clothing, said container having an air inlet and an air outlet to the sampling unit; the assembly being heated by a temperature controlled heater; (b) an air sampling unit able to take a sample of the air from the container and to divert said sample to enter the sensor set; (c) a selected definitive sensor set comprising at least two sensors known to react to the presence of the specific odours or volatile organic compounds ( VOCs) in the air sample which are known to indicate the presence of a specific disease or diseases, and (d) a processing unit comprising a pattern recognition analyser, wherein the pattern recognition analyser receives output signals of the sensor set compares them to disease-specific patterns derived from a database of response patterns of the sensor set to the breath or other body sweat emissions of subjects with known diseases, wherein each of the disease-specific patterns is characteristic of a particular disease, both bacteriological or viral; and selects a closest match between the output signals of the sensor set and the disease-specific pattern.

This method does not detect the specific bacteria or virus associated with a disease rather it detects the presence of a combination of odours or Volatile Organic Compounds which are generated in the subject as a reaction to the infection. With a suitable array of sensors and appropriate processing of their reactions it is possible to build up a digital fingerprint which is specific to a single disease. With a library of such digital fingerprints stored within the apparatus it becomes possible, through a process of comparison, to identify the presence of disease even when two or more are present in one subject. It has been found that in the case of diseases caused by viral infections the indicative combinations of odours or Volatile Organic Compounds will include, but not be limited to, chemical compounds from the aldehydes (ethanal, heptanal, octanal), ketones (acetone, butanone) and methanol (D.M. Ruszkiewicz et al., Diagnosis of COVID-19 by analysis of breath with gas chromatography-ion mobility spectrometry -a feasibility study, EClinicalMedicine (2020).

In the case of diseases caused by bacterial infections the indicative combinations of odours or Volatile Organic Compounds will include, but not be limited to, chemical compounds from the alcohols (3-methyl-butanol, propan-2-ol), aldehydes (propanal, hexanal, 3-methyl-butanal) and sulphur compounds (methyl sulphide, dimethyl sulphide) group.

The sensitivity of the system can be enhanced by inserting a piece of material known to absorb odours or Volatile Organic Compounds into the face mask or clothing. Suitable commercially available absorbent materials include but are not limited to, Tenax TA, Tenax GR, Carbotrap, Carbopack B and C. Carbotrap C, Carboxen, Car bosieve Sill, Proapak, Spherocarb, and combinations thereof; preferred adsorbent combinations include, but are not limited to, Tenax GR and Carbopack B: Carbopack B and Carbosieve Sill; and Carbopack C and Carbopack Band Carbosieve Sill or Carboxen 1000. Those skilled in the art will know of other suitable absorbent materials.

It further becomes possible following the outbreak of a previously unknown disease to adapt the apparatus to detect the new disease by sampling and measuring the odours or Volatile Organic Compounds emitted by subjects infected with the new disease and to determine the digital fingerprint describing the combination of odours or Volatile Organic Compounds identifying said disease. The apparatus could then have its digital library and software updated to include the new disease. All the historical measurements with time and date codes could be stored in memory for subsequent review and auditing.

A BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of the components of a system in accordance with the invention that includes several optional components; FIG. 2 is a diagrammatic perspective view of a portable handheld monitoring unit system in accordance with the invention; FIG. 3 shows the typical responses of a sensor set or array when exposed to the full body odours or Volatile Organic Compounds firstly from subjects not infected with the disease and secondly from subjects infected with the disease.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a preferred embodiment of the apparatus. This includes an air inlet 1 open to the atmosphere of the environment; a mask or clothing sample 2 and associated heater 3; and a container 5 for housing the mask or clothing sample. A pipe 4 routes the air sample from the container 5 to a diverter valve 6. This valve has a changeover function and can connect the sensor set 9 to the sample pipe 4 or to the fresh air pipe 8; via the optional air filter 7. This air is used to purge or clean the sensor set after each sampling and measuring sequence. The air is pulled through the sensor set by the air pump 14 which exhausts into outlet 15. This outlet may incorporate an optional air filter 16 containing suitable absorbent material to limit the risk of releasing any infected material into the general atmosphere. The sensor set 9 is connected to the electronic processor system 10 which is also connected to the optional display 11; the optional control panel 12; the electrical power supply 13; the optional wireless connection 17; a wired connection 18 to an external computer or other apparatus and an optional audible or visual alarm 19 to provide an alert following detection of a disease.

FIG. 2 is a diagrammatic perspective view of a portable handheld monitoring unit system in accordance with the invention; within the housing 20 there could typically be the components shown in FIG.1.

FIG.3. Shows the amplitude responses of a sensor set or array when (a) exposed to the atmosphere containing the odours or Volatile Organic Compounds emitted from subjects not infected with the disease (Healthy), (b) when exposed to the atmosphere containing the odours or Volatile Organic Compounds emitted from subjects infected with the disease (Infected) and c) the difference between the Infected and Healthy. These illustrative results were taken with the specific disease Campylobacter Infection. In this case the sensor responses are differentiated by the maximum amplitude deviation from baseline, with the difference between the Infected and healthy the criteria for analysis, but there are many other more complex pattern recognition techniques which might be implemented depending on the application. Such techniques include, but are not limited to, K-nearest neighbour (KNN), Canonical Discriminate Analysis (CDA), Soft Independent Modelling of Class Analogy (SIMCA), probabilistic neural network (PNN), artificial neural network (ANN), support vector machine (SVM), Linear Discriminant Analysis (LDA) and Fisher Linear Discriminate (FLD).

Although the invention has been described in detail with reference to the presently preferred embodiments, those of ordinary skill in the art will appreciate that various modifications can be made without departing from the invention.

Claims

CLAIMSAccordingly, the invention is defined only by the following claims:- 1. An apparatus which will detect a viral or bacterial disease in a subject by measuring and analysing and making comparison with the digital fingerprints of the odours or Volatile Organic Compounds released from the subject's breath previously absorbed into a previously worn face mask; and, the system comprising: (a) a housing into which the face mask can be inserted also containing a heater whose temperature can be controlled between 30 and 90 degrees Celsius, (b) an air sampling unit able to take a sample of the odours or Volatile Organic Compounds emitted by the face mask heated inside said container and to divert said sample to enter the sensor set; (b) a selected definitive sensor set comprising at least two sensors reactive to the presence of specific odours or Volatile Organic Compounds (VOCs) in the air sample taken from the mask sample; and (c) a processing unit comprising a pattern recognition analyser, wherein the pattern recognition analyser receives output signals of the sensor set; compares them to disease-specific patterns derived from a database of response patterns of the sensor set exposed to the breath samples of subjects with known disease, wherein each of the disease-specific patterns is characteristic of a particular disease, both bacteriological or viral; and selects a closest match between the output signals of the sensor set and the disease-specific pattern and all contained within (d) an overall housing.
2. The method of claim 1, wherein the apparatus will detect a viral or bacterial disease in a subject by measuring and analysing and making comparison with the digital fingerprints of the odours or Volatile Organic Compounds released from the subject's body sweat previously absorbed into a previously worn piece of clothing; and, the system comprising: (a) a housing into which the sample of clothing can be inserted also containing a heater whose temperature can be controlled between 30 and 90 degrees Celsius, (b) an air sampling unit able to take a sample of the odours or Volatile Organic Compounds emitted by the clothing heated inside said container and to divert said sample to enter the sensor set; (b) a selected definitive sensor set comprising at least two sensors reactive to the presence of specific odours or Volatile Organic Compounds ( VOCs) in the air sample taken from the clothing; and (c) a processing unit comprising a pattern recognition analyser, wherein the pattern recognition analyser receives output signals of the sensor set; compares them to disease-specific patterns derived from a database of response patterns of the sensor set exposed to the body sweat samples of subjects with known disease, wherein each of the disease-specific patterns is characteristic of a particular disease, both bacteriological or viral; and selects a closest match between the output signals of the sensor set and the disease-specific pattern and all contained within (d) an overall housing.
3. The method of claim 1, wherein at least one other sensor is selected from the group consisting of surface acoustic wave sensors, quartz crystal resonators, metal oxide sensors, dye-coated fibre optic sensors, micro-machined cantilever arrays, composites having regions of conducting material and regions of insulating organic material, composites having regions of conducting material and regions of conducting or semi-conducting organic material, chemically-sensitive resistor or capacitor film, semi-conducting polymer sensors, metal-oxide-semiconductor field effect transistors, and bulk organic conducting polymeric sensors.
4. The method of claim 1, wherein said test sample comprises the odours or Volatile Organic Compounds emanating from either breath samples released from a previously worn face mask or from body sweat samples released from previously worn clothing 5. The method of claim 1, wherein the container 5 for enclosing the face mask or clothing sample is made removable and disposable to enhance the biosecurity of the system.6. The method of claim 1, wherein the data is analysed by comparing the data to a database containing data profiles from a plurality of detectable signals and identifying the at least one specific odour or Volatile Organic Compound present in the sample thereby characterizing the disease or combinations of diseases.7. The method of claim 1, wherein the disease or diseases causing the illness in the subject is of bacteriological or viral origin.8. The system according to claim 1 wherein the database comprises response patterns of the sensor set when sampling odours or Volatile Organic Compounds emanating from the group consisting of breath samples and body sweat samples having a bodily origin of subjects suffering from a known disease.9. The system according to claim 1, with a method of diagnosing, screening or monitoring the presence of a disease or diseases in a test subject in a non-invasive manner by sampling the atmosphere around the subject, the method comprising the steps of: (a) providing a system according to claim 1; (b) exposing the sensor set to the odours or Volatile Organic Compounds emanating from the group consisting of breath samples or body sweat samples; (c) measuring the output signals of the sensor set upon exposure to the said sample; (d) comparing the output signals using a pattern recognition analyser to the database -derived disease-specific patterns; and (e) selecting the closest match between the output signals of the sensor set and the database-derived disease specific patterns and applying a tolerance between the output signals of the sensor set and the database-derived disease specific patterns, to indicate a Pass or a Fail (Infected or Non-Infected) condition.10. The system according to claim 1 with the addition of a wireless communication device, including but not limited to Wi-Fi; Bluetoothe and Telephone SMS messaging, to enable a warning signal to be transmitted in the event of a disease or diseases being detected in the location in which it is being monitored.11. The system according to claim 1 with the addition of an air filter unit, including but not limited to a capsule of carbon granules or carbon impregnated cloth, and being capable of adsorbing odours and Volatile Compounds, said air filter unit purifying the air used to clean and purge the sensor set before the next sampling and measurement sequence.12. The system according to claim 1 with the addition of an air filter unit, including but not limited to a capsule of adsorbent material carbon granules or carbon impregnated cloth, said air filter unit being inserted ahead of the air outlet to limit the risk of releasing any infected material into the general atmosphere.13. The system according to claim 1 with the provision of a computer or other memory and being capable of recording every measurement taken by every sensor in the sensor set together with date and time records; these records being downloaded through an electrical or wireless connection to said apparatus.14. The method of claim 1, wherein the disease-specific patterns in the database can be added to with new disease-specific patterns characterising a disease or diseases not previously included in the database of response patterns of the sensor set to the odour or Volatile Organic Compound emissions from the breath or body sweat of subjects with known diseases.15. In the method of claim 1 wherein the cases of diseases caused by viral infections the indicative combinations of odours or Volatile Organic Compounds will include, but not be limited to, chemical compounds from the aldehydes, ketones and alcohols group and in the case of diseases caused by bacterial infections the indicative combinations of odours or Volatile Organic Compounds will include, but not be limited to, chemical compounds from the alcohols, aldehydes and sulphides group.16. The system according to claim 1 with the sensitivity of the system being enhanced by the insertion of a piece of material, known to absorb odours or Volatile Organic Compounds, into the face mask or clothing. Suitable commercially available absorbent materials include but are not limited to, Tenax TA, Tenax GR, Carbotrap, Carbopack B and C. Carbotrap C, Carboxen, Carbosieve Sill, Proapak, Spherocarb, and combinations thereof; preferred adsorbent combinations include, but are not limited to, Tenax OR and Carbopack B: Carbopack B and Carbosieve Sill; and Carbopack C and Carbopack Band Carbosieve SIII or Carboxen 1000. Those skilled in the art will know of other suitable absorbent materials.