Patent Publication Number: US-2023143974-A1

Title: Portable device for detecting and quantifying a concentration of a marker present in a sample of biological fluid

Description:
The present invention relates to a portable device for detecting and quantifying a concentration of a marker present in a sample of biological fluid. 
     In particular, the present invention relates to a highly sensitive portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which is capable of detecting and determining concentrations of the marker up to 0.01 ng/L. 
     Such a device finds particular application in the medical and personal care fields, for quantifying the concentration of a marker, for example TROPONIN I, in a user&#39;s blood or plasma sample. 
     As is known, cardiovascular diseases, and especially acute coronary syndromes, are among the most common diseases and currently represent the cause of about half of all deaths in the Western world. Conditions related to cardiovascular diseases cost the European Union around 192 billion euros annually, representing a significant financial burden on healthcare resources. 
     One of the most dangerous forms of acute coronary syndromes is myocardial infarction, defined as necrosis of the cardiac myocytes following prolonged ischemia. Since myocardial infarction causes irreversible damage to the heart, a patient suspected of having such a disease must be diagnosed as quickly and efficiently as possible. 
     To this end, various tests are performed, such as the electrocardiogram and the measurement of specific biomarkers in the patient&#39;s blood. 
     However, for hospital admissions related to acute coronary syndromes, up to 50% of patients show an EKG reading which is considered normal or contains ambiguous information. Therefore, the assessment of the variation in the concentration of cardiac disease markers (referred to below as cardiac markers) is currently the most accurate source of information to allow the doctor to make an informed decision on the appropriate treatment for the patient. 
     The internationally recognized guidelines for the diagnosis of cardiac markers recommend a detection of TROPONIN I concentration in the blood starting from 5 ng/L in the blood sample and also recommend a response time for reporting results which is less than 60 minutes. In other words, the report of the tests carried out on the patient must be available within 60 minutes of the patient&#39;s admission. 
     However, such a guideline in terms of response time has proved problematic, as less than 25% of hospitals have successfully achieved the aforesaid goal. 
     It follows that, generally, the patient must wait longer than 60 minutes before being able to receive adequate healthcare treatment, putting his health at risk for the aforesaid reasons. 
     Furthermore, the patient&#39;s waiting inside the healthcare facility, in addition to being risky and unpleasant for the same patient, involves a further series of disadvantages, such as the possible filling of specific spaces in the healthcare facility or the financial burden deriving from the patient&#39;s prolonged stay. 
     Therefore, a strongly felt need in the sector is that of being able to rapidly measure the concentrations of markers, especially cardiac markers, so as to be able to efficiently initiate the healthcare treatment. 
     To meet this need, some point-of-care (POCT) devices have been made commercially available for identifying and determining the concentration of cardiac markers. 
     The expression “point-of-care devices” refers to all those devices allowing tests which can be performed near the patient and/or in the place where specific healthcare is provided and which simultaneously allow to promptly provide results. 
     In other words, such devices allow the patient to perform the tests in the doctor&#39;s office, in an ambulance, at home or in the hospital and allow healthcare personnel to obtain results quickly. 
     Consequently, Point-of-Care Testing is currently the most suitable organizational solution for correct and effective decentralized diagnostics, with constant control of the analytical quality by an analysis laboratory. 
     There are currently several Point-of-Care devices on the market intended for the diagnosis of myocardial infarction which operate by determining the concentration of cardiac markers, such as TROPONIN I. 
     Such devices for detecting and quantifying TROPONIN I are based on different analytical techniques. 
     For example, devices based on the electrochemical technique, on the detection technique by fluorescence spectroscopy or on the detection technique by infrared spectroscopy (FTIR) are known. 
     However, such devices have a series of disadvantages which make the use thereof still not very efficient. 
     First of all, none of the devices is capable of complying with the recommendations from the guidelines for the diagnosis of cardiac markers, as such devices have a TROPONIN I detection limit in a blood sample of not less than 20 ng/L, i.e., almost five times greater than the established value. 
     A further disadvantage of such devices is related to the large volumes (&gt;100 μL) of biological sample required for the normal analysis operations and/or the need to pre-treat the biological sample (for example the separation of plasma or serum from the blood sample). 
     Another disadvantage is the cost of the devices, which make the purchase thereof prohibitive. 
     Such factors make the devices usable exclusively by healthcare professionals. 
     In this context, the technical task underlying the present invention is to propose a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which overcomes the drawbacks of the prior art mentioned above. 
     In particular, it is an object of the present invention to provide a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which can comply with the criteria recommended by the guidelines regarding detection sensitivity and precision. 
     It is a further object of the present invention to provide a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which can be easily used even by unskilled personnel and/or by the patient himself/herself. 
     It is a further object of the present invention to provide a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which is capable of providing results rapidly. 
     It is a further object of the present invention to provide a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which is precise and reliable. 
     It is a further object of the present invention to provide a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which requires a small volume of biological sample for correct operation. 
     It is a further object of the present invention to provide a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which is easily and comfortably transportable, in particular by the user himself. 
     It is a further object of the present invention to provide a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which is easily available on the market and which has a low cost. 
     The specified technical task and objects are substantially achieved by a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample which is easy to use, comprising the technical features set out in one or more of the appended claims. 
     In particular, the specified technical task and objects are substantially achieved by a portable device for detecting and quantifying a concentration of a marker, for example TROPONIN I, present in a biological fluid sample, comprising a cartridge adapted to receive the biological fluid sample and comprising at least one reactive agent configured to bind to the marker, defining an electrochemiluminescent solution. The cartridge is preferably coupled to an electrode cell configured to supply electrical energy to the electrochemiluminescent solution so as to trigger an electrochemiluminescence reaction of the electrochemiluminescent solution, generating a light signal representative of a concentration value of the marker in the biological fluid sample. The device further comprises an analyzer, connectable to the cartridge and configured to receive and analyze at least one property of the light signal so as to quantify a concentration of the marker in the biological fluid. 
    
    
     
       Further features of the present invention will become more apparent from the following indicative and thus non-limiting description of a preferred, but not exclusive, embodiment of such a device, as shown in the accompanying drawings, in which: 
         FIGS.  1 A and  1 B  respectively show a diagrammatic perspective view and a diagrammatic top view of an embodiment of a cartridge for a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample in accordance with the present invention; 
         FIG.  2    shows a diagrammatic section of the cartridge in  FIG.  1   ; and 
         FIG.  3    shows an embodiment diagram of an analyzer for the portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample according to the present invention, during a use configuration in which the cartridge is connected to the analyzer. 
     
    
    
     With reference to the accompanying drawings, reference numeral  1  generally indicates a portable device for detecting and quantifying a concentration of a marker present in a biological fluid sample. 
     In the present description, the expression “biological fluid sample” is intended as human biomaterial, substantially in liquid form, sampled or which can be sampled from a subject. 
     Preferably, the expression “biological fluid sample” refers to a blood or plasma sample. 
     According to a preferred embodiment of the device  1 , it finds application for detecting and quantifying a concentration of the marker TROPONIN I in blood or plasma. 
     However, according to alternative embodiments, which are not excluded from the scope of the present patent application, such a device  1  can be advantageously used for detecting and quantifying a concentration of a generic marker in a biological fluid sample, such as blood, plasma, saliva and urine. 
     For example, such a device can be used as a serological test for detecting and quantifying the antibodies produced in the event of infection due to the presence of a virus belonging to the coronavirus family. 
     Substantially, the device  1  comprises a cartridge  100  and an analyzer  200 . 
     The cartridge  100  is configured to receive the biological fluid sample and comprises at least one reactive agent configured to bind to the marker, defining an electrochemiluminescent solution. 
     In the present description, the term “bind” is intended as the formation of a bond, preferably of a chemical nature, which holds the at least one reactive agent and the marker together. 
       FIGS.  1 A,  1 B and  2    show an exemplary and non-limiting embodiment of the cartridge  100 . 
     In such an embodiment, the cartridge  100  has a substantially parallelepiped shape. 
     The cartridge  100  is made of rigid material, preferably of polymeric material, even more preferably of polyester. 
     According to an aspect of the present invention, the cartridge  100  has a length between 4 cm and 8 cm, preferably 6 cm, a width between 1.5 cm and 2.5 cm, preferably 2 cm, and a thickness between 0.6 cm and 1.5 cm, preferably 0.8 cm. 
     Advantageously, the reduced size of the cartridge  100  allow the user to comfortably carry one or more cartridges  100  therewith. 
     Advantageously, moreover, such size allow the user to be able to store, for example in his own home, a plurality of cartridges  100  in a limited space, in order to have a supply always available in case of need. 
     The cartridge  100  can comprise a chamber  102  for receiving the biological fluid sample, preferably with a conical or frustoconical shape, adapted to collect the biological fluid sample. 
     Said receiving chamber  102  can further comprise a sampling element, not illustrated, configured to achieve an extraction of the biological fluid sample from a user when in contact with the user. For example, the sampling element can comprise a fingerstick or a lancing device. 
     Alternatively, the receiving chamber  102  can be configured to receive the biological fluid sample by means of a known alternative instrument, such as a transfer pipette or any equivalent instrument. 
     The cartridge  100  can comprise a first and a second reaction chamber, indicated in the figures with the respective reference numerals  103  and  104 . 
     The first reaction chamber  103  is arranged in fluid communication with the receiving chamber  102  and comprises a first reactive agent configured to bind to the marker of the biological fluid sample. 
     Preferably, such a first reactive agent can be a secondary antibody configured to bind to TROPONIN I. 
     According to a first embodiment, the first reaction chamber  103  comprises a microfluidic channel  103   a , interposed between the receiving chamber  102  and the second reaction chamber  104 , and configured for a transport of the biological fluid sample from the receiving chamber  102  to the second reaction chamber  104 . 
     According to such an embodiment, the first reaction chamber  103  is also at least partially coincident with the receiving chamber  102 . 
     Preferably the first reactive agent is applied to a bottom wall of the receiving chamber  102  and is configured to detach from the bottom wall when in contact with the biological fluid sample. 
     In other words, the biological fluid sample is received in the receiving chamber  102  where it comes into contact with the first reactive agent, applied to the bottom of the receiving chamber  102 , which binds to the marker detaching itself from the bottom walls and defining the aforesaid electrochemiluminescent solution. 
     A chemical and/or physical barrier  105  can also be present, interposed between the receiving chamber  102  and the second reaction chamber  104 , configured to break apart after a certain period of time from a first contact between the barrier  105  and the biological fluid sample so as to slow down a movement of the biological fluid sample from the receiving chamber  102  to the second reaction chamber  104 . Preferably, such a period of time is between 2 minutes and 10 minutes. Even more preferably, the period of time is equal to 5 minutes. 
     Such a barrier  105  is preferably operatively arranged before the microfluidic channel  103   a.    
     Advantageously, by virtue of such a barrier  105 , the first reactive agent has time to bind to the marker before the biological fluid sample reaches the second reaction chamber  104  through the microfluidic channel  103   a.    
     According to a further embodiment, the first reactive agent is preferably applied at least on the walls of the microfluidic channel  103   a  and is configured to detach from the walls when in contact with the biological fluid sample. 
     Furthermore, in such an embodiment, the barrier  105  is operatively arranged in a joining portion between the microfluidic channel  103   a  and the second reaction chamber  104 . In other words, the barrier  105  is operatively arranged near an end of the microfluidic channel  103   a  connected and facing the second reaction chamber  104 . 
     Such a microfluidic channel  103   a  can have a circular, square or rectangular section and has a width having a value between 40 μm and 500 μm, preferably equal to 80 μm. 
     Advantageously, the size of the microfluidic channel  103   a  causes a movement of the biological fluid sample which occurs substantially by capillarity. 
     It follows that the movement of the biological fluid sample inside the microfluidic channel  103   a  is slow enough to allow an optimal mixing of the first reactive agent with the biological fluid sample itself, defining the aforementioned electrochemiluminescent solution. 
     Functionally, in other words, the biological fluid sample from the receiving chamber  102  enters by capillarity inside the microfluidic channel  103   a  where it comes into contact with the first reactive agent which binds to the marker, detaching itself from the walls of the microfluidic channel and defining the aforesaid electrochemiluminescent solution. 
     According to a further embodiment, the first reactive agent can be applied both on the walls of the microfluidic channel  103   a  and on the bottom wall of the receiving chamber  102 . 
     The second reaction chamber  104 , arranged in fluid communication with the first reaction chamber  103 , comprises a second reactive agent configured to also bind to the biological fluid sample marker. 
     Preferably, such a first reactive agent can be a primary antibody configured to bind to TROPONIN I. 
     Advantageously, the first and the second reactive agents are stable and non-toxic. 
     The cartridge  100  further comprises an electrode cell  101 . 
     Such an electrode cell  101  is preferably inserted in the second reaction chamber  104 . 
     Even more preferably, the electrode cell  101  is operatively arranged in a bottom portion  104   b  of the second reaction chamber  104 . 
     In other words, the second reaction chamber  104  defines, together with the electrode cell  101 , an electrochemical cell. 
     The electrode cell  101  is configured to supply electrical energy to the electrochemiluminescent solution so as to trigger an electrochemiluminescence reaction of the electrochemiluminescent solution capable of generating a light signal representative of a concentration of the marker in the biological fluid sample. 
     Preferably, the cartridge  100  is therefore disposable. 
     Structurally, the electrode cell  101  can comprise a working electrode, a reference electrode and an auxiliary electrode. 
     Preferably, the second reactive agent is applied to the working electrode. 
     At a functional level, the electrode cell  101  is preferably configured to generate a potential difference between distinct points, and in particular between the working electrode and the reference electrode, so as to cause a chemical reaction in the second reaction chamber  104 . 
     Advantageously, by using a three-electrode cell  101  to activate the electrochemiluminescence reaction, it is possible to precisely control the reaction. 
     In other words, by means of the energy supplied by the electrode cell  101 , an electrochemiluminescent reaction occurs inside the second reaction chamber  104 . 
     According to a further structural aspect, the working electrode can be made of vitreous carbon or gold or platinum, the reference electrode can be made of silver or silver chloride while the auxiliary electrode can be made of vitreous carbon or gold or platinum. 
     The cartridge  100  can further comprise a washing chamber  106 , arranged in fluid communication with the second reaction chamber  104  and comprising an absorption element  106   a  configured to absorb and remove an excess portion of the electrochemiluminescent solution from the second reaction chamber  104 . 
     By virtue of such a washing chamber  106  it is therefore possible to normalize the quantity of electrochemiluminescent solution necessary for the electrochemiluminescence reaction. 
     The excess portion can be a portion of the excess biological fluid sample and/or a portion of the first reactive agent not bound to the marker and/or a portion of the second reactive agent not bound to the marker. 
     Preferably, the washing chamber  106  absorbs the electrochemiluminescent solution component not bound to the electrode cell. 
     Preferably, the washing chamber  106  is operatively arranged in a position opposite to the first receiving chamber  103  with respect to the second reaction chamber  104 . 
     In other words, the second reaction chamber  104  is interposed between the washing chamber  106  and the first reaction chamber  103 . 
     Preferably, the absorption element  106   a  is made of hydrophilic material. Even more preferably, the absorption element  106   a  is made of cellulose diacetate. 
     The electrode cell  101  is powered by an electric generator. 
     In this regard, the cartridge  101  can comprise a connector  107 , preferably a normalized connector of the hot swap type, even more preferably a USB connector, configured for a reversible coupling with a source of electricity. 
     In other words, such a connector  107  acts as a generator for the electrode cell  101 . 
     Such a connector  107  can be applied to any compatible interface which is suitable for supplying electrical energy. 
     Preferably, the connector  107  can be applied directly to a receiving portion  201  of the analyzer  200 , as will be seen in the following of the present description. In other words, in such an embodiment, the connector  107  is configured to activate the electrode cell  101  when the cartridge is connected to the analyzer  200 . 
     As seen in the accompanying drawings, the second reaction chamber  104  comprises a covering element  104   a , transparent to the electromagnetic radiation generated by the electrochemiluminescence reaction so as to allow the reception of the light signal by the analyzer  200 . 
     In the present description, the expression “transparent to electromagnetic radiation” means that the covering element  104   a  allows the passage of the light signal produced by the electrochemiluminescence reaction. 
     Said covering element  104   a  is operatively arranged in a position opposite to the electrode cell  101  with respect to the second reaction chamber  104 . 
     In other words, the second reaction chamber  104  is at least partially delimited at the bottom by the electrode cell  101  operatively arranged in the bottom portion  104   b  and is delimited at the top by the covering element  104   a.    
     Advantageously, such a covering element  104   a  has the dual function of protecting the second reaction chamber  104  and allowing the electromagnetic radiation of the light signal to reach the analyzer  200  which is, in use, operatively arranged in a position such as to be able to receive the light signal. 
     In particular, the analyzer  200  is connectable or connected to the cartridge  100  to receive and analyze at least one property of the light signal so as to quantify a concentration value of the marker in the biological fluid. 
     Advantageously, the electrochemiluminescence technique allows to optimally analyze a large variety of biological samples, such as blood, plasma, serum, saliva, urine and cellular supernatant. 
     Furthermore, the sensitivity and precision of such a system are very high, allowing the detection and determination of marker concentrations up to 0.01 ng/L. 
     According to a preferred embodiment, illustrated by way of non-limiting example in  FIG.  3   , the analyzer  200  can comprise an optical sensor  202 , arranged above the covering element  104   a  and oriented in the direction of the covering element  104   a  when the cartridge  100  is connected to the analyzer  200 . 
     The optical sensor  202  is configured to measure a light intensity value of the light signal emitted by the electrochemiluminescence reaction. 
     The analyzer  200  can comprise a converter of the light signal captured by the optical sensor so as to convert the light signal of an analog nature into a digital one. 
     The analyzer  200  further comprises a control unit “U”, connected to the optical sensor  202  and configured to determine the concentration of the marker as a function of the light intensity value measured by the optical sensor  202  and to generate information content representative of the concentration of said marker in said biological fluid sample. 
     Preferably, by analyzing the light signal coming from the optical sensor  202 , the control unit “U” determines the quantification of the presence of the marker as a function of the light intensity of the light signal itself. 
     Functionally, the at least one reactive agent binds to the marker, generating an electrochemiluminescent solution which is activated by the electrode cell  101 . The more marker present in the biological fluid sample, the more the electrochemiluminescent solution will emit photons. Consequently, by measuring the properties of the light signal emitted by the electrochemiluminescent solution, the analyzer  200  will be capable of determining the concentration of the marker since it is proportional to the electrochemiluminescent solution and therefore to the intensity of the light signal. 
     The analyzer  200  can further comprise a video and/or audio emission system  203  connected to the control unit “U” to receive the information content and configured to emit a visual and/or sound signal corresponding to the information content, so that the user can receive a visual/audible feedback of the measurement made. 
     For example, the video and/or audio emission system  203  can comprise at least one of a display, preferably digital, and at least one speaker. 
     According to an aspect of the present invention, the analyzer  200  can further comprise a communication system configured to transmit the information content to an external receiving unit. 
     For example, the analyzer  200  can comprise a wireless communication system for remote communication. 
     For example, if the device  1  is used on a patient during transport by ambulance, the test result can be sent directly to the healthcare facility where the patient is directed, so that he can immediately be subjected to a specific treatment. 
     Also, in the situation where the device  1  is used in one&#39;s home, the device sends the result of the test to the healthcare facility where the device user is being treated. 
     The analyzer  200  can have compact size so that it can be transported by a user. 
     According to a further aspect, the analyzer  200  can be powered by a power supply connectable to the electrical grid and/or have a support battery thereof and/or have a rechargeable battery. 
     According to a further aspect, the device  1  can comprise a plurality of cartridges  100  (a set or a kit) reversibly connectable to the analyzer  200 , each cartridge  100  comprising a respective reactive agent configured to bind to a respective marker. 
     Advantageously, such a device  1  can thereby be used for detecting and determining the concentration of a plurality of markers. 
     Advantageously, according to an embodiment, the device  1  can be used for detecting a marker identifying the presence of a virus belonging to the coronavirus family. 
     Advantageously, according to an embodiment, the device  1  can be used for detecting the antibodies produced following infection due to the presence of a virus belonging to the coronavirus family. 
     For example, the device  1  can be advantageously used for detecting and quantifying a viral load of the severe acute respiratory syndrome from coronavirus  2  present in a biological fluid sample. 
     The present invention achieves the suggested objects, overcoming the drawbacks reported in the prior art. 
     Advantageously, the portable device  1  for detecting and quantifying a concentration of a marker present in a biological fluid sample can be easily used even by unskilled personnel and/or by the user himself. 
     Such a result is achieved by virtue of the structure of the cartridge  100  which determines the intuitive use thereof and by virtue of the analyzer  200  which operates in a completely automated manner and also allows rapid feedback to be provided to the user. 
     Advantageously, in fact, the portable device  1  for detecting and quantifying a concentration of a marker present in a biological fluid sample is capable of providing the results rapidly, precisely and by means of a low volume of biological fluid sample. 
     Such a result is achieved by virtue of the technical features of the cartridge  100  which allow triggering the chemiluminescence reaction in a few minutes and with a small biological fluid sample and by virtue of the technical features of the analyzer  200  which allow a very rapid and precise analysis by exploiting the electrochemiluminescence reaction. 
     A further object achieved is that of providing a portable device  1  for detecting and quantifying a concentration of a marker present in a biological fluid sample which is easily and comfortably transportable, in particular by the user himself. Such a result is achieved by virtue of the small size of the cartridge  100  and the analyzer  200 .