Not applicable.
Centralized clinical testing of diagnostics is expensive and time consuming, causing delays in health care delivery. Often point of need testing and diagnostic assays lack the ability to provide quantitative and diagnostic information. In some cases, it may be useful in both clinical and non-clinical settings to provide a point of need testing system to address these and other issues.
The present disclosure provides, by way of various example embodiments, systems and methods for a point of need testing system. The point of need testing system includes a first collector and a sample amplifier. The first collector is configured to collect a first biofluid sample. The sample amplifier is configured for performing an amplification reaction to generate amplification products of a target nucleic acid to produce a second biofluid sample. The sample amplifier may comprise a reagent reservoir containing one or more reagents for performing the amplification reaction to generate amplification products of the target nucleic acid and, optionally, a control nucleic acid. The sample amplifier may further includes an inlet dimensioned to receive the first biofluid sample from the first collector, a filter, a heater, a second collector, or any combination thereof. In some embodiments, the sample amplifier further includes an indicator configured to produce an indication that the second biofluid sample has been produced from the first biofluid sample. In some embodiments, a reader can be used with the sample amplifier to read a second biofluid produced by the sample amplifier.
In some embodiments, a point of need testing system can include a reader. The ready may be configured to accept the second biofluid sample and produce an output. The reader can include a heater configured to heat the second biofluid sample, a lateral flow test strip, a detection site, an excitation array, a photodetector, or any combination thereof. In some embodiments, a photodetector can be configured to communicate a signal wirelessly.
In some embodiments, a point of need testing system includes a sample amplifier that is separate from the reader. The sample amplifier can be configured as a portable sample amplifier and the reader can be configured as a stationary reader so that the portable sample amplifier can be brought into contact with the stationary reader to accept the biofluid sample.
In some embodiments, a method of testing a biofluid sample is disclosed. The method includes collecting a first biofluid sample, filtering the first biofluid sample to remove particulate, heating the first biofluid sample in the presence of one or more reagents for performing an amplification reaction to generate amplification products of a target nucleic acid to produce a second biofluid sample; collecting the second biofluid sample, transporting the second biofluid sample to a detection site, irradiating the second biofluid sample at the detection site, and detecting emitted electromagnetic radiation indicative of the presence or absence of the target nucleic acid and, optionally, a control nucleic acid. The method may be performed with any of the point of need testing systems described herein.
In some embodiments, a method of testing a biofluid sample can include obtaining a first biofluid sample by inserting the biofluid into a biofluid collector. The method can include inserting the biofluid sample into a sample amplifier by rotating the biofluid collector and employing gravity to move the biofluid from the biofluid collector to the sample amplifier.
In some embodiments, a method of testing a biofluid sample can including transmitting a result to a processor. The method can also include decoding electromagnetic radiation intensity detected by a photodetector.
The accompanying drawings, which are incorporated in and form a part of this specification, illustrate example embodiments of the invention and, together with the description, serve to explain the principles of certain embodiments.
The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art after having studied the teachings in this disclosure, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans, after having studied the teachings in this disclosure, will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention.
A point of need (or point-of-care) testing system for use in clinical and non-clinical settings is described below. It can be generally useful to quantitatively test a biological fluid (“biofluid”) sample. In some embodiments, the biofluid can include, without limitation, saliva, blood, serum, urine, cerebrospinal fluid, interstitial fluid, and other fluid samples. The point of need testing systems generally operate by detecting the presence or absence of a target nucleic acid. This may be accomplished by amplifying a target nucleic acid to prepare an amplification products that can be detected with a reader.
In particular embodiments, the testing system can be used to test a biofluid sample that has been allotted appropriate reaction time to amplify one or more target nucleic acids, including target nucleic acids indicative of potential pathogens, or control nucleic acids within the biofluid sample to generate amplification products. An “amplification product” or “amplicon” is a piece of nucleic acid that is the product of amplification or replication events. The amplification product may also be a source of further amplification or replication events. The “amplification” refers to production of one or more copies of nucleic acid sequence. Amplification of the nucleic acid sequence may be accomplished by various amplification methods known in the art including isothermal and non-isothermal amplification methods.
As used herein, “subject” or “patient” refers to mammals and non-mammals. A “mammal” may be any member of the class Mammalia including, but not limited to, humans, non-human primates (e.g., chimpanzees, other apes, and monkey species), farm animals (e.g., cattle, horses, sheep, goats, and swine), domestic animals (e.g., rabbits, dogs, and cats), or laboratory animals including rodents (e.g., rats, mice, and guinea pigs). Examples of non-mammals include, but are not limited to, birds, and the like. The term “subject” does not denote a particular age or sex. In one specific embodiment, a subject is a mammal, preferably a human. The subject may have or suffer from, or be suspected of having or suffering from, a disease, condition, or disorder.
In some embodiments, the subject may have or suffer from, or be suspected of having or suffering from, an infection by a pathogen. “Pathogen” means an organism that can produce disease in a subject. Examples of pathogens include, without limitation, viruses, bacteria, fungi, and parasites.
The target nucleic acid and the control nucleic acid can, but need not, originate from the same source. For example, the target nucleic acid may originate from a pathogen and the control nucleic acid may originate from the subject. In other embodiments, the both the target and control nucleic acids may originate from the subject. In yet other embodiments, the both the target and control nucleic acids may originate from a pathogen.
Some nucleic acid amplification processes can take close to an hour (e.g., approximately 45 minutes to 75 minutes) for target nucleic acids in a biofluid to be properly amplified into a detection sample. In some cases, it may be useful for a user to start the amplification process prior to arriving at a sample reader that reads the detection sample.
In some embodiments, the systems and devices of this disclosure are capable of analyzing samples at the point-of-need rather than in a laboratory. As used herein, the term “point of need” or “point of care” can be defined to mean a location on or near a site of patient care where medical or medically related services such as medical testing and/or treatment are provided, including but not limited to hospitals, emergency departments, intensive care units, primary care setting, medical centers, patient homes, physician offices, pharmacies, or sites of an emergency.
In some embodiments, the systems and devices of this disclosure are capable of analyzing samples to provide point-of-entry style testing. As used herein, the term “point of entry” can be defined as an entry point to a variety of workplaces or gathering locations, such as, for example, airports, train stations, nursing homes, schools, etc. Allowing for the testing of samples collected at or brought to the entry point aids in restricting access to the workplace or gathering location for those who test positive. Further, in some embodiments, the systems and devices of this disclosure are capable of analyzing samples at home to provide regular checks of individuals in a multi-family environment, such as assisted living facilities, dormitories, etc. In some embodiments, systems and devices of this disclosure include software that permits wirelessly transmitting test results to trusted parties including the individual being tested, the location allowing (or denying) entry, and healthcare entities.
The advantages of the systems and devices of this disclosure are multifold and include, for example, the benefit of shortening the time between sample collection and analysis, thereby identifying subjects having particular test results and, if appropriate, providing medical treatment sooner than traditionally possible with conventional diagnostic systems.
Further illustrated in
In other embodiments, sonication can be used to apply sound energy to agitate particles in the biofluid sample to move the biofluid sample from the biofluid collector 104 into the sample amplifier 108. In other embodiments, capillary flow may be used to induce a flow of the biofluid sample from the biofluid collector 104 to the sample amplifier 108. In other embodiments, a pressure difference created between the biofluid collector 104 and the sample amplifier 108 when the biofluid collector 104 is secured to the sample amplifier 108 can force the biofluid from the biofluid collector 104 to the sample amplifier 108.
In some embodiments, sample amplifier 108 may provide compounds or compositions suitable for use with point of need diagnostic devices or other biological assays. Suitably, the sample amplifier 108 may include, without limitation, buffers, surfactants, chaotropic salts, proteases such as poteninase K, chelating agents such as EDTA, co-factors, salts such as chaotropic salts, carrier RNA, or any combination thereof.
In the illustrated embodiment, the sample amplifier includes a housing 124 that houses a filter 128, a heater 132, a reagent reservoir 136, and a second biofluid collector 140. The housing 124 may selectively provide access to an interior of the housing 124 from an exterior of the housing 124. In some embodiments, access to the interior of the housing 124 can allow the user to remove, replace, dispose, and/or recharge certain components within the housing 124, as will be described in greater detail below.
The filter 128 in the illustrated embodiment is a filter configured to remove particulates from biofluid. In some embodiments, the filter is a mechanical, affinity, adsorption, or chemical bonding filter. As those of ordinary skill in the art will readily recognize and appreciate after having studied and benefited from the teachings in this disclosure, a variety of mechanical filters may be used, such as filter employing mesh membranes, beads, pores, or other filtering apparatuses. In some embodiments, particulates can include unwanted particles in the biofluid that are not useful to (or may hinder) amplifying nucleic acids in the biofluid. Such particles can include residual food particles from saliva, for example. The filter 128 may be disposable and replaceable within the sample amplifier 108 such that a user can remove the filter 128 after use and replace the filter 128 with an unused filter.
The heater 132 in the illustrated embodiment is configured to heat the biofluid sample within the sample amplifier 108. In some embodiments, the heater 132 may be reusable between biofluid samples within the housing 124. The heat provided by the heater 132 can accelerate the reaction kinetics of an amplification reaction of the target nucleic acid within the biofluid sample with reagents in the reagent reservoir 136.
The reagent reservoir 136 contains one or more reagents for performing an amplification technique therein to generate amplification products or amplicons of the target or control nucleic acid. Suitably, the reagent reservoir may contain a primer, a strand-displacing DNA polymerase, a reverse transcriptase, a DNA helicase, or any combination thereof. Like the filter 128, the reagent reservoir 136 may be disposable and replaceable within the sample amplifier 108 such that the user can remove the reagent reservoir 136 after use and replace the reagent reservoir 136 with an unused reservoir.
After a predetermined amount of time, the sample amplifier 108 can convert the biofluid sample into a second, processed biofluid sample which can be used as a detection sample as will be described below. The processed biofluid sample may contain amplification products or amplicons suitable for detection, thereby providing qualitative or quantitative information on the presence or absence of the target nucleic acid in the biofluid. The second biofluid collector 140 can collect (or receive) and retain the detection sample.
In some embodiments, the heater 132 may include a first heater and a second heater. The first heater may be placed proximate to a top of the biofluid sample and the second heater may be placed proximate to a bottom of the biofluid sample in the device. In an area that is proximate to the reagent reservoir 136, the biofluid sample may be surrounded by a thermally conductive material, such as copper, for example, to promote even heating provided by the heater 132 at the area proximate to the reagent reservoir 136.
In some embodiments, the sample amplifier 108 can further include an indicator (not shown). The indicator can include one or more of an audio, visual, or tactile indication. For example, the indicator may output a light (e.g., a green light) when a predetermined amount of time has passed from when the biofluid first entered the sample amplifier 108. In some embodiments, a user may initiate the sample amplifier via a start actuator, such as a button or a switch, for example, which begins the countdown from the predetermined amount of time. In other embodiments, a timer armed with the predetermined amount of time may be started once the biofluid collector 104 is secured to the sample amplifier 108. In some embodiments, the predetermined amount of time may be between approximately 15 minutes and 90 minutes. In other embodiments, the predetermined amount of time may be between approximately 30 minutes and 60 minutes. In general, the predetermined amount of time is the time required for the biofluid to be reacted and amplified such that the detection sample can be read by the reader 112.
The lateral flow strip 148 is proximate to the inlet 160 and can transport the detection sample from the second biofluid collector 140 to the detection site 156. The lateral flow strip 148 enables flow through capillary forces. In alternative embodiments, a channel that allows for flow driven by pressure may substitute for the lateral flow strop. Suitably, the lateral flow strip 148 or channel may include reagents, such as reagents for performing an amplification technique or compounds or compositions suitable for use with point of need diagnostic devices or other biological assays. The second biofluid collector 140 may include a paper-based membrane or microfluidic channel that is configured to induce capillary flow from the second biofluid collector 140 to the lateral flow strip 148. In some embodiments, the heater 152 may heat the detection sample as the detection sample is transported along the lateral flow strip 148 and is received at the detection site 156. Heating the lateral flow strip 148 or detection site 156 allows for the amplification reaction to be accomplished in whole or in part within the lateral flow strip 148 or detection site 156.
The detection site 156 can be positioned between an excitation array 164 and a photodetector 168. Optionally, an optical filter (not shown) may be positioned between the excitation array 164 and the detection site 156 or an optical filter (not shown) may be positioned between the detection site 156 and the photodetector 168. In some embodiments, optical filters are positioned between excitation array 164 and the detection site 156 and the detection site 156 and the photodetector 168.
The excitation array 164 provides electromagnetic radiation that may be absorbed by the detection sample. The electromagnetic radiation may be of any suitable wavelength that can provide a detectable signal indicating the presence or absence of an amplification product of a target nucleic acid. In some embodiments, the electromagnetic radiation may be of any suitable wavelength that can provide a detectable signal indicating the presence or absence of an amplification product of a control nucleic acid. In some embodiments, the excitation array 164 provides electromagnetic radiation in the infrared, visible, or ultraviolet spectrums. The excitation array 164 may emit broadband or narrowband electromagnetic spectrums. An optical filter provided between the excitation array 164 and the detection site 156 may be used to selectively provide the wavelengths within a desired spectral window to the detection site 156.
The photodetector 168 may detect any suitable wavelength or electromagnetic radiation. In some embodiments, the photodetector 168 detects electromagnetic radiation in the infrared, visible, or ultraviolet spectrums. The photodetector 168 may include an array connected to a readout circuit, which can include a microchip. The photodetector 168 can wirelessly or wiredly communicate to a processor (not shown) that can decode and translate intensities sent via a digital signal that originate from a current signal. The detection sample may include biomarkers, chromophores, fluorophores, dyes, and other compounds or substances capable of emit light of a second wavelength or color when stimulated by a first light of a first wavelength or color. The presence of amplification products of the target and/or control nucleic acid sequence in the second biofluid sample may alter electromagnetic radiation intensity emitted at the second wavelength relative to an amplification product free second biofluid sample. The photodetector 168 can detect the light of the second color and output the current which is then transmitted to the processor. The intensity of the detected light allows for determination of the presence or absence of the target nucleic acid and/or control nucleic acid target. The processor can output qualitative or quantitative results that can be used for epidemiological data collection and studies.
An optical filter provided between the detection site 156 and the photodetector 168 may be used to select selectively provide wavelengths within a desired spectral window to the photodetector 168. When optical filters are positioned between excitation array 164 and the detection site 156 and the detection site 156 and the photodetector 168, the optical filter positioned between excitation array 164 and the detection site 156 may selectively provide the wavelength of the first color and the optical filter positioned between the detection site 156 and the photodetector 168 may selectively provide the wavelength of the second color. Such an embodiment may minimize the electromagnetic radiation provided by the excitation array 164 being provided directly to the photodetector 168.
In some embodiments, the reader 112 can further include an indicator (not shown). The indicator can include one or more of an audio, visual, or tactile indication. For example, the indicator may output a light (e.g., a green light or a red light) if a specific pathogen at a predetermined level is found (or not found) in the detection sample. Similar to the sample amplifier 108, elements of the reader 112 may be reusable. For example, the heater and components of the detection site 156 such as the photodetector, excitation array, and the microchip. Correspondingly, the lateral flow strip 148 may be replaceable within the housing 144 which can be selectively accessible from the outside.
In some embodiments, the first device of the method 200 may be separate from the second device. However, in other embodiments, the first device may be fluidly coupled to the second device such that steps 240 and 250 of the method 200 are unnecessary.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
This application claims priority to U.S. provisional patent application No. 63/039,208, titled Point of Need Diagnostic with Thermal Control and filed Jun. 15, 2020, the entirety of which is incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/037447 | 6/15/2021 | WO |
Number | Date | Country | |
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63039208 | Jun 2020 | US |