We thank Susanne Lopes Rasmussen and Solvej Kolbj&#248;rn Jensen for their technical assistance and for handling the clinical samples. This project is part of the EbolaMoDRAD consortium, which has received funding from the Innovative Medicine Initiative 2 Joint Undertaking under grant agreement N&#176;115843. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation program and EFPIA.

The Committee on Biomedical Research Ethics, Capital region has given informed consent, and all methods described here have been exempted from a review by the ethical committee system, in accordance with the Danish law on assay development projects.
1. Preparation of Blood Collection Vacuum Tubes for Virus Inactivation and Rapid NA Extraction
CAUTION: The buffer used for this protocol contains guanidinium thiocyanate (GITC) and a non-ionic surfactant, which are irritants. Take appropriate laboratory safety measures, use a flow hood, and wear gloves when handling it. Avoid any skin and eye contact. If the buffer is spilled, the contaminated surface must never be disinfected directly with chloramine or sodium hypochlorite (the active ingredients in &#34;bleach&#34;) because this mixture may lead to the formation of toxic cyanide. First, wipe up the spilled buffer with the absorbent tissue. Next, clean the surface with 70% ethanol and then with water, and finally, use chloramine or sodium hypochlorite.
<ol>
	<li>To prepare the blood collection vacuum tubes, inject 1.6 mL of the specific commercial lysis buffer into a 4 mL EDTA vacuum tube by puncturing the lid of the tube using a 25 G x 1 needle and a 3 mL syringe. 
	NOTE: Do not remove the lid of the vacuum tube. The vacuum must be maintained.</li>
	<li>Store the vacuum tubes containing the buffer at room temperature until use. 
	NOTE: The tubes are stable for at least 1 year after their preparation.</li>
</ol>
2. Preparation of Buffers for NA Extraction
<ol>
	<li>To prepare the buffers for an NA extraction, place two 1.8 mL, two 4.5 mL, and one 3.6 mL tubes in a rack.</li>
	<li>Add, by pipetting, 960 &#181;L of magnetic glass particles (MGPs) to a clean 1.8 mL tube and label it with MGPs. Resuspend the MGP suspension completely before pipetting it. 
	NOTE: The MGPs tend to quickly collect at the bottom of the tube.</li>
	<li>Add, by pipetting, 4 mL of wash buffer I to a clean 4.5 mL tube and label it as WB-1. 
	CAUTION: Wash buffer I contains guanidinium chloride, which is irritant. Take appropriate laboratory safety measures, use a flow hood, and wear gloves when handling it. Avoid any skin and eye contact.</li>
	<li>Add, by pipetting, 1.5 mL of wash buffer II to a clean 3.6 mL tube and label it as WB-2.</li>
	<li>Add, by pipetting, 3 mL of wash buffer III to a clean 4.5 mL tube and label it as WB-3.</li>
	<li>Add, by pipetting, 100 &#181;L of elution buffer to a clean 1.8 mL tube and label it as EB.</li>
	<li>Store the aliquoted buffers at room temperature until use. 
	NOTE: The tubes are stable for at least 1 month after their preparation.</li>
</ol>
3. Blood Collection from Patients with Signs and Symptoms of a Virus Infection
CAUTION: Take appropriate laboratory safety measures when collecting whole blood from the patient. Wear gloves and glasses. If the patient is in isolation, please follow biosafety level 4 procedures.
<ol>
	<li>To collect intravenous whole blood from the patient, use a butterfly needle with small-bore extension tubing and a blood collection vacuum tube containing a lysis/binding buffer. Rest the patient&#39;s arm in a downward position and position the collection tube lower than the butterfly needle. Insert the butterfly needle into the vein of the patient and attach the blood collection vacuum tube to the small-bore extension. 
	NOTE: This will prevent back-flow.</li>
	<li>After the blood collection, mix the contents of the tube by flipping the tube 5 - 10 times. 
	NOTE: Due to the remaining vacuum in the blood collection tube containing 1.6 mL of lysis/binding buffer, the volume of the sample collected will automatically be 1.6 mL.</li>
	<li>Disinfect the outside of the tube using 70% ethanol.</li>
	<li>Incubate the tubes for 20 min at room temperature. 
	NOTE: The protocol can be paused here and the full blood collection tubes can be stored at -20 &#176;C, 5 &#176;C, 25 &#176;C or 37 &#176;C for at least 1 month7.</li>
	<li>Continue directly to the simplified NA extraction method.</li>
</ol>
4. Simplified NA Extraction of the Whole Blood
<ol>
	<li>To purify NA from the lysis/binding buffer-inactivated collected blood, mix the contents of the tube by flipping the vacuum tube by hand 5 - 10x.</li>
	<li>Remove the lid of the tube carefully and discharge the lid.</li>
	<li>Pour the prepared aliquot of MGPs (1 mL) directly into the blood collection tube.</li>
	<li>Place a new lid from an unused blood collection tube on the tube containing the sample.</li>
	<li>Place a finger on the lid to ensure that the tube is tightly closed and mix the contents of the tube by flipping the blood collection tube by hand 5 - 10 times.</li>
	<li>Place the tube in the magnetic holder and keep a finger on the lid to ensure the tube is tightly closed.</li>
	<li>Flip the magnetic holder with the tube a few times by hand to make sure that all the MGPs are collected at the side of the tube with the magnet. 
	NOTE: The magnetic holder can be replaced with an elongated magnet and a rubber band.</li>
	<li>Remove the lid of the tube and discard the contents of the tube either by using a disposable pipette or simply by pouring the contents into a 50 mL collection tube. 
	NOTE: Avoid aerosols from the 50 mL collection tube by closing the tube with a lid.</li>
	<li>Pour the prepared aliquot of WB-1 (4 mL) directly into the blood collection tube.</li>
	<li>Place the lid on the tube and place a finger on the lid to ensure the tube is tightly closed.</li>
	<li>Remove the tube from the magnetic holder, keeping the lid securely tightened with a finger. 
	NOTE: If using a magnet and a rubber band, simply remove the rubber band and magnet from the tube.</li>
	<li>Resuspend the MGPs by flipping the blood collection tube by hand 5 - 10 times.</li>
	<li>Repeat steps 4.6&#160;- 4.8.</li>
	<li>Pour the prepared aliquot of WB-2 (1.5 mL) directly into the blood collection tube.</li>
	<li>Place the lid on the tube and remove the tube from the magnetic holder. 
	NOTE: If using a magnet and a rubber band, simply remove the rubber band and magnet from the tube.</li>
	<li>Place a finger on the lid to ensure the tube is tightly closed.</li>
	<li>Resuspend the MGPs by flipping the blood collection tube for a few seconds by hand.</li>
	<li>Repeat step 4.6&#160;- 4.8.</li>
	<li>Pour the prepared aliquot of WB-3 (3 mL) directly into the blood collection tube.</li>
	<li>Place the lid on the tube and remove the tube from the magnetic holder. 
	NOTE: If using a magnet and a rubber band, simply remove the rubber band and magnet from the tube.</li>
	<li>Place a finger on the lid to ensure the tube is tightly closed.</li>
	<li>Resuspend the MGPs by flipping the blood collection tube by hand 5 - 10 times.</li>
	<li>Repeat steps 4.6&#160;- 4.8.</li>
	<li>Pour the prepared aliquot of EB (100 &#181;L) directly into the blood collection tube.</li>
	<li>Place the lid on the tube and remove the tube from the magnetic holder. 
	NOTE: If using a magnet and a rubber band, simply remove the rubber band and magnet from the tube.</li>
	<li>Resuspend the MGPs in the EB by tapping the blood collection tube 5 - 10 times with a finger. 
	NOTE: The protocol can be paused here, and the tubes can be stored at -20 &#176;C.</li>
	<li>Transfer one droplet (5 - 8 &#181;L) of the resuspended MGPs to the downstream NA amplification reaction mix using a 1.5 mL disposable pipette (any downstream diagnostic NA amplification assay such as LAMP/RT-LAMP or qPCR/RT-qPCR assays can be used). 
	NOTE: The NAs will stick to the MGPs, so be sure to use the MGPs in the downstream NA amplification reaction. Mix the MGP suspension before use. After mixing, the MGPs will collect at the bottom of the tube.</li>
</ol>

<ol>
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J., Weller, S. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Buffer+AVL+alone+does+not+inactivate+Ebola+virus+in+a+representative+clinical+sample+type.">Buffer AVL alone does not inactivate Ebola virus in a representative clinical sample type.</a> Journal of Clinical Microbiology. 53 (10), 3148-3154 (2015).</li><li>Byrnes, S., Fan, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Portable,+Pressure+Driven,+Room+Temperature+Nucleic+Acid+Extraction+and+Storage+System+for+Point+of+Care+Molecular+Diagnostics.">A Portable, Pressure Driven, Room Temperature Nucleic Acid Extraction and Storage System for Point of Care Molecular Diagnostics.</a> Analytical Methods. 5 (13), 3177-3184 (2013).</li><li>Rosenstierne, M. 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The authors have nothing to disclose.

In this report, we describe a safe, rapid, and simple manual bedside NA extraction method for the downstream molecular detection of a virus in lysis/binding buffer-inactivated whole blood. The described NA extraction method was developed to be performed directly on whole blood samples collected in vacuum blood collection tubes containing the lysis/binding buffer (Table of Materials)7. This specific buffer inactivates EBOV7 and is the critical component in t...

In virus outbreak situations, when patients are confined to the hospital isolation wards or when a fast diagnosis is needed, a safe, simple, and accurate point-of-care molecular diagnosis is imperative for the patient care and risk containment. The two recent viral outbreaks, of the Ebola virus (EBOV) in West Africa (2013) and the Zika virus in South America (2015), have increased the interest in improved point-of-care molecular diagnostic tests, such as reverse transcription loop-mediated isothermal amplification (RT-LAMP)1,2 and recombinase polymerase amplification (RPA)3,4. Both RT-LAMP and RPA are rapid, sensitive, and specific molecular tests that can be performed on simplified sample preparations. For the Zika virus, RT-LAMP has been combined with a lateral flow assay (LFA), which can detect Zika virus in non-purified whole blood samples within 30 min1; however, for EBOV, which is classified as a risk group 4 pathogen and is highly contagious, the samples need to be handled under biosafety level 4 (BSL-4) conditions and inactivated before any safe diagnostic procedures can be performed.
Simplified inactivation methods for EBOV, such as the addition of lysis buffers to the sample2,3,4,5, were used during the outbreak; however, these methods require&#160;handling under BSL-4 conditions with laboratory equipment, such as BSL-3 biosafety cabinets, centrifuges, heating blocks, and pipettes, at a minimum. This equipment is normally not present in isolation wards or out in field hospitals. To overcome this challenge, attempts have been made to perform diagnostics in suitcases3, and several portable devices and machines have been developed [e.g., a portable device for nucleic acid (NA) extraction]6. However, EBOV-positive samples still need to be inactivated before these devices can be used.
We have previously reported a rapid bedside virus inactivation method for the EBOV7, Vaccinia virus, and Cowpox virus8 by addition of a commercial lysis/binding buffer to ordinary vacuum blood collection tubes, allowing for the direct transfer of blood from the patient into the inactivation buffer7. This direct and immediate inactivation in a closed system eliminates the need for handling the samples using any rigorous containment, such as BSL-4 conditions7, and the samples can be handled under normal BSL-2 conditions. This inactivation method is compatible with several NA extraction systems, such as robots and hand purification kits7; however, these methods require laboratory equipment, such as robots, centrifuges, and electricity, which are not always present in field settings or inside hospital isolation wards.
In this report, we describe a safe, rapid, and simplified manual NA extraction method for the subsequent molecular detection of a virus in lysis/binding buffer-inactivated whole blood. The NA extraction method does not require any equipment other than a magnet/magnetic holder. No centrifuges, heating blocks, or electricity are needed for the NA extraction. Hence, this method is not dependent on laboratory facilities and can easily be used anywhere (e.g., in field hospitals, in hospital isolation wards, or with low-resource settings). The NA extraction method is rapid and simple and can be used directly in any downstream NA tests, such as qPCR, RT-qPCR, LAMP, or RT-LAMP. When this NA extraction method is combined with LAMP and a portable battery-driven isothermal instrument, a bedside diagnosis can be obtained within 40 min of the blood collection.

<table><tbody><tr><td>Vacutainer K2 EDTA tubes (4 mL)</td><td>Becton Dickinson</td><td>368861</td><td></td></tr><tr><td>Plus Blood Collection</td><td>Becton Dickinson</td><td>362725</td><td></td></tr><tr><td>23G x 1 needle</td><td>Becton Dickinson</td><td>300800</td><td></td></tr><tr><td>LUER LOK syringe (3 mL)</td><td>Becton Dickinson</td><td>309658</td><td></td></tr><tr><td>Butterfly needle with small-bore extension tubing</td><td>J&amp;oslash;rgen Kruuse A/S</td><td>121714</td><td></td></tr><tr><td>1% Virkon</td><td>Nomeco A/S</td><td>849265</td><td></td></tr><tr><td>MagNA Pure LC DNA Isolation Kit I - Lysis/Binding Buffer - Refill</td><td>Roche Diagnostics A/S</td><td>03246752001</td><td></td></tr><tr><td>MagNA Pure LC Total Nucleic Acid Isolation Kit</td><td>Roche Diagnostics A/S</td><td>3038505001</td><td></td></tr><tr><td>Nunc&amp;trade; Biobanking and Cell Culture Cryogenic Tubes (1,8 mL)</td><td>Thermo Fisher Scientific</td><td>375418</td><td></td></tr><tr><td>Nunc&amp;trade; Biobanking and Cell Culture Cryogenic Tubes (3,6 mL)</td><td>Thermo Fisher Scientific</td><td>379189</td><td></td></tr><tr><td>Nunc&amp;trade; Biobanking and Cell Culture Cryogenic Tubes (4,5 mL)</td><td>Thermo Fisher Scientific</td><td>379146</td><td></td></tr><tr><td>DynaMag&amp;trade;-5 Magnet</td><td>Thermo Fisher Scientific</td><td>12303D</td><td></td></tr><tr><td>Transfer pipette (3.5 mL)</td><td>Sarstedt</td><td>86.1171.010</td><td></td></tr><tr><td>Thermo Scientific&amp;trade; Samco&amp;trade; Fine Tip Transfer Pipettes (1.5 mL)</td><td>Thermo Fisher Scientific</td><td>231</td><td></td></tr><tr><td>Thermo Scientific&amp;trade; Nunc&amp;trade; 50 mL Conical Sterile Polypropylene Centrifuge Tubes</td><td>Thermo Fisher Scientific</td><td>339652</td><td></td></tr></tbody></table>

rapid, safe, and simple manual bedside nucleic acid extraction for the detection of virus in whole blood samples

The rapid diagnosis of an infection is essential for the outbreak management, risk containment, and patient care. We have previously shown a method for the rapid bedside inactivation of the Ebola virus during blood sampling for safe nucleic acid (NA) tests by adding a commercial lysis/binding buffer directly into the vacuum blood collection tubes. Using this bedside inactivation approach, we have developed a safe, rapid, and simplified bedside NA extraction method for the subsequent detection of a virus in lysis/binding buffer-inactivated whole blood. The NA extraction is directly performed in the blood collection tubes and requires no equipment or electricity. 
After the blood is collected into the lysis/binding buffer, the contents are mixed by flipping the tube by hand, and the mixture is incubated for 20 min at room temperature. Magnetic glass particles (MGPs) are added to the tube, and the contents are mixed by flipping the collection tube by hand. The MGPs are then collected on the side of the blood collection tube using a magnetic holder or a magnet and a rubber band. The MGPs are washed three times, and after the addition of elution buffer directly into the collection tube, the NAs are ready for NA tests, such as qPCR or isothermal loop amplification (LAMP), without the removal of the MGPs from the reaction. The NA extraction method is not dependent on any laboratory facilities and can easily be used anywhere (e.g., in field hospitals and hospital isolation wards). When this NA extraction method is combined with LAMP and a portable instrument, a diagnosis can be obtained within 40 min of the blood collection.

The protocol presented here is simple and efficient and can be broadly applied to any molecular assay to be performed on infectious whole blood samples inactivated with the lysis/binding buffer. The workflow for the blood inactivation and NA extraction is shown in Figure 1, including the preparation of blood collection vacuum tubes7 (Figure 1A), the blood collection7 (<strong class=...

Watch this Scientific Journal Video about Rapid, Safe, and Simple Manual Bedside Nucleic Acid Extraction for the Detection of Virus in Whole Blood Samples at JoVE.com

Rapid, Safe, and Simple Manual Bedside Nucleic Acid Extraction for the Detection of Virus in Whole Blood Samples

Here, we present a protocol for the rapid virus nucleic acid extraction from the virus-inactivated whole blood. The extraction is performed directly in the blood collection tubes and requires no equipment or electricity. The method is not dependent on laboratory facilities and can be used anywhere (e.g., in field hospitals).

The rapid diagnosis of an infection is essential for the outbreak management, risk containment, and patient care. We have previously shown a method for ...

rapid-safe-simple-manual-bedside-nucleic-acid-extraction-for

Research

JoVE Journal

Immunology and Infection

7.3K Views.  Statens Serum Institut. Hier presenteren we een protocol voor de snelle virus nucleïnezuur extractie van de volbloed virus-geïnactiveerd. De winning gebeurt rechtstreeks in het bloed collectie buizen en vereist geen apparatuur of elektriciteit. De methode is niet afhankelijk van laboratoriumfaciliteiten en kan overal worden gebruikt (bijvoorbeeld, in veldhospitalen).

Video: Rapid, Safe, and Simple Manual Bedside Nucleic Acid Extraction for the Detection of Virus in Whole Blood Samples

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Part III. Virus Detection by RT-qPCR

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a standardized method for use in multiple analytical laboratories during monitoring period 3 of the Unregulated Contaminant Monitoring Rule. Herein we present the protocol for extraction of viral ribonucleic acid (RNA) from water sample concentrates and for quantitatively measuring enterovirus and norovirus concentrations using reverse transcription-quantitative PCR (RT-qPCR). Virus concentrations for the molecular assay are calculated in terms of genomic copies of viral RNA per liter based upon a standard curve. The method uses a number of quality controls to increase data quality and to reduce interlaboratory and intralaboratory variation. The method has been evaluated by examining virus recovery from ground and reagent grade waters seeded with poliovirus type 3 and murine norovirus as a surrogate for human noroviruses. Mean poliovirus recoveries were 20% in groundwaters and 44% in reagent grade water. Mean murine norovirus recoveries with the RT-qPCR assay were 30% in groundwaters and 4% in reagent grade water.

Here we present a procedure to quantify enterovirus and norovirus in environmental and drinking waters using reverse transcription-quantitative PCR. Mean virus recovery from groundwater with this standardized procedure from EPA Method 1615 was 20% for poliovirus and 30% for murine norovirus.

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a ...

Environment

High-throughput, Automated Extraction of DNA and RNA from Clinical Samples using TruTip Technology on Common Liquid Handling Robots

TruTip is a simple nucleic acid extraction technology whereby a porous, monolithic binding matrix is inserted into a pipette tip. The geometry of the monolith can be adapted for specific pipette tips ranging in volume from 1.0 to 5.0 ml. The large porosity of the monolith enables viscous or complex samples to readily pass through it with minimal fluidic backpressure. Bi-directional flow maximizes residence time between the monolith and sample, and enables large sample volumes to be processed within a single TruTip. The fundamental steps, irrespective of sample volume or TruTip geometry, include cell lysis, nucleic acid binding to the inner pores of the TruTip monolith, washing away unbound sample components and lysis buffers, and eluting purified and concentrated nucleic acids into an appropriate buffer. The attributes and adaptability of TruTip are demonstrated in three automated clinical sample processing protocols using an Eppendorf epMotion 5070, Hamilton STAR and STARplus liquid handling robots, including RNA isolation from nasopharyngeal aspirate, genomic DNA isolation from whole blood, and fetal DNA extraction and enrichment from large volumes of maternal plasma (respectively).

TruTip is a simple nucleic acid extraction technology whereby a porous, monolithic binding matrix is inserted into a pipette tip. Consequently, the sample preparation format is compatible with most liquid handling instruments, and can be used for many medium to high-throughput clinical applications and sample types.

TruTip is a simple nucleic acid extraction  technology whereby a porous, monolithic binding matrix is inserted into a  pipette tip. The geometry of the ...

Bioengineering

Detection of Viruses from Bioaerosols Using Anion Exchange Resin

This protocol demonstrates a customized bioaerosol sampling method for viruses. In this system, anion exchange resin is coupled with liquid impingement-based air sampling devices for efficacious concentration of negatively-charged viruses from bioaerosols. Thus, the resin serves as an additional concentration step in the bioaerosol sampling workflow. Nucleic acid extraction of the viral particles is then performed directly from the anion exchange resin, with the resulting sample suitable for molecular analyses. Further, this protocol describes a custom-built bioaerosol chamber capable of generating virus-laden bioaerosols under a variety of environmental conditions and allowing for continuous monitoring of environmental variables such as temperature, humidity, wind speed, and aerosol mass concentration. The main advantage of using this protocol is increased sensitivity of viral detection, as assessed via direct comparison to an unmodified conventional liquid impinger. Other advantages include the potential to concentrate diverse negatively-charged viruses, the low cost of anion exchange resin (~$0.14 per sample), and ease of use. Disadvantages include the inability of this protocol to assess infectivity of resin-adsorbed viral particles, and potentially the need for the optimization of the liquid sampling buffer used within the impinger.

An anion exchange resin-based method, adapted to liquid impingement-based bioaerosol sampling of viruses is demonstrated. When coupled with downstream molecular detection, the method allows for facile and sensitive detection of viruses from bioaerosols.

This protocol demonstrates a customized bioaerosol sampling method for viruses. In this system, anion exchange resin is coupled with liquid ...

VirWaTest, A Point-of-Use Method for the Detection of Viruses in Water Samples

Viruses excreted by humans and animals may contaminate water sources and pose a risk to human health when this water is used for drinking, food irrigation, washing, etc. The classical fecal bacteria indicator does not always check for the presence of viral pathogens so the detection of viral pathogens and viral indicators is relevant in order to adopt measures of risk mitigation, especially in humanitarian scenarios and in areas where water-borne viral outbreaks are frequent.
At present, several commercial tests allowing the quantification of fecal indicator bacteria (FIB) are available for testing at the point of use. However, such commercial tests are not available for the detection of viruses. The detection of viruses in environmental water samples requires concentrating several liters into smaller volumes. Moreover, once concentrated, the detection of viruses relies on methods such as nucleic acid extraction and molecular detection (e.g., polymerase chain reaction [PCR]-based assays) of the viral genomes.
The method described here allows the concentration of viruses from 10 L water samples, as well as the extraction of viral nucleic acids at the point of use, with simple and portable equipment. This allows the testing of water samples at the point of use for several viruses and is useful in humanitarian scenarios, as well as at any context where an equipped laboratory is not available. Alternatively, the method allows concentrating viruses present in water samples and the shipping of the concentrate to a laboratory at room temperature for further analysis.

Here we present VirWaTest, which is a simple, affordable and portable method for the concentration and detection of viruses from water samples at the point of use.

Viruses excreted by humans and animals may contaminate water sources and pose a risk to human health when this water is used for drinking, food ...

Electricity-Free, Sequential Nucleic Acid and Protein Isolation

Traditional and emerging pathogens such as Enterohemorrhagic Escherichia coli (EHEC), Yersinia pestis, or prion-based diseases are of significant concern for governments, industries and medical professionals worldwide. For example, EHECs, combined with Shigella, are responsible for the deaths of approximately 325,000 children each year and are particularly prevalent in the developing world where laboratory-based identification, common in the United States, is unavailable 1. The development and distribution of low cost, field-based, point-of-care tools to aid in the rapid identification and/or diagnosis of pathogens or disease markers could dramatically alter disease progression and patient prognosis. We have developed a tool to isolate nucleic acids and proteins from a sample by solid-phase extraction (SPE) without electricity or associated laboratory equipment 2. The isolated macromolecules can be used for diagnosis either in a forward lab or using field-based point-of-care platforms. Importantly, this method provides for the direct comparison of nucleic acid and protein data from an un-split sample, offering a confidence through corroboration of genomic and proteomic analysis.
Our isolation tool utilizes the industry standard for solid-phase nucleic acid isolation, the BOOM technology, which isolates nucleic acids from a chaotropic salt solution, usually guanidine isothiocyanate, through binding to silica-based particles or filters 3. CUBRC's proprietary solid-phase extraction chemistry is used to purify protein from chaotropic salt solutions, in this case, from the waste or flow-thru following nucleic acid isolation4.
By packaging well-characterized chemistries into a small, inexpensive and simple platform, we have generated a portable system for nucleic acid and protein extraction that can be performed under a variety of conditions. The isolated nucleic acids are stable and can be transported to a position where power is available for PCR amplification while the protein content can immediately be analyzed by hand held or other immunological-based assays. The rapid identification of disease markers in the field could significantly alter the patient's outcome by directing the proper course of treatment at an earlier stage of disease progression. The tool and method described are suitable for use with virtually any infectious agent and offer the user the redundancy of multi-macromolecule type analyses while simultaneously reducing their logistical burden.

A tool and chemistries are described to sequentially isolate nucleic acids followed by proteins from a sample without the need for electricity. The tool consists of a sorbent held within a transfer pipette while the isolation chemistries are based on solid-phase extraction principles. The isolated macromolecules can be analyzed by immuno-based and PCR-based assays.

Traditional and emerging pathogens such as Enterohemorrhagic Escherichia coli (EHEC), Yersinia pestis, or prion-based diseases are of significant concern ...

Biology

Efficient SARS-CoV-2 Quantitative Reverse Transcriptase PCR Saliva Diagnostic Strategy utilizing Open-Source Pipetting Robots

The emergence of the recent SARS-CoV-2 global health crisis introduced key challenges for epidemiological research and clinical testing. Characterized by a high rate of transmission and low mortality, the COVID-19 pandemic necessitated accurate and efficient diagnostic testing, particularly in closed populations such as residential universities. Initial availability of nucleic acid testing, like nasopharyngeal swabs, was limited due to supply chain pressure which also delayed reporting of test results. Saliva-based reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) testing has shown to be comparable in sensitivity and specificity to other testing methods, and saliva collection is less physically invasive to participants. Consequently, we developed a multiplex RT-qPCR diagnostic assay for population surveillance of Clemson University and the surrounding community. The assay utilized open-source liquid handling robots and thermocyclers instead of complex clinical automation systems to optimize workflow and system flexibility. Automation of saliva-based RT-qPCR enables rapid and accurate detection of a wide range of viral RNA concentrations for both large- and small-scale testing demands. The average turnaround for the automated system was &#60; 9 h for 95% of samples and &#60; 24 h for 99% of samples. The cost for a single test was $2.80 when all reagents were purchased in bulk quantities.

The protocol describes a SARS-CoV-2 diagnostic method that utilizes open-source automation to perform RT-qPCR molecular testing of saliva samples. This scalable approach can be applied to clinical public health surveillance as well as to increase the capacity of smaller university laboratories.

The emergence of the recent SARS-CoV-2 global health crisis introduced key challenges for epidemiological research and clinical testing. Characterized by ...

Filtration Isolation of Nucleic Acids:  A Simple and Rapid DNA Extraction Method

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad to extract cellular DNA from whole blood in less than 2 min. The blood specimen is treated with detergent, mixed briefly and applied by pipet to the separation membrane. The lysate wicks into the blotting pad due to capillary action, capturing the genomic DNA on the surface of the separation membrane. The extracted DNA is retained on the membrane during a simple wash step wherein PCR inhibitors are wicked into the absorbent blotting pad. The membrane containing the entrapped DNA is then added to the PCR reaction without further purification. This simple method does not require laboratory equipment and can be easily implemented with inexpensive laboratory supplies. Here we describe a protocol for highly sensitive detection and quantitation of HIV-1 proviral DNA from 100 &#181;l whole blood as a model for early infant diagnosis of HIV that could readily be adapted to other genetic targets.

We describe here a simple and rapid paper-based DNA extraction method of HIV proviral DNA from whole blood detected by quantitative PCR. This protocol can be extended for use in detecting other genetic markers or using alternative amplification methods.

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad ...

Two-Step Reverse Transcription Droplet Digital PCR Protocols for SARS-CoV-2 Detection and Quantification

Diagnosis of the ongoing SARS-CoV-2 pandemic is a priority for all countries across the globe. Currently, reverse transcription quantitative PCR (RT-qPCR) is the gold standard for SARS-CoV-2 diagnosis as no permanent solution is available. However effective this technique may be, research has emerged showing its limitations in detection and diagnosis especially when it comes to low abundant targets. In contrast, droplet digital PCR (ddPCR), a recent emerging technology with superior advantages over qPCR, has been shown to overcome the challenges of RT-qPCR in diagnosis of SARS-CoV-2 from low abundant target samples. Prospectively, in this article, the capabilities of RT-ddPCR are further expanded by showing steps on how to develop simplex, duplex, triplex probe mix, and quadruplex assays using a two-color detection system. Using primers and probes targeting specific sites of the SARS-CoV-2 genome (N, ORF1ab, RPP30, and RBD2), the development of these assays is shown to be possible. Additionally, step by step detailed protocols, notes, and suggestions on how to improve the assays workflow and analyze data are provided. Adapting this workflow in future works will ensure that the maximum number of targets can be sensitively detected in a small sample significantly improving on cost and sample throughput.

This work summarizes steps on developing different assays for SARS-CoV-2 detection using a two color ddPCR system. The steps are elaborate and notes have been included on how to improve the assays and experiment performance. These assays may be used for multiple SARS-CoV-2 RT-ddPCR applications.

Diagnosis of the ongoing SARS-CoV-2 pandemic is a priority for all countries across the globe. Currently, reverse transcription quantitative PCR (RT-qPCR) ...

Swabbing the Urban Environment - A Pipeline for Sampling and Detection of SARS-CoV-2 From Environmental Reservoirs

To control community transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the 2020 global pandemic, most countries implemented strategies based on direct human testing, face covering, and surface disinfection. Under the assumption that the main route of transmission includes aerosols and respiratory droplets, efforts to detect SARS-CoV-2 in fomites have focused on locations suspected of high prevalence (e.g., hospital wards, cruise ships, and mass transportation systems). To investigate the presence of SARS-CoV-2 on surfaces in the urban environment that are rarely cleaned and&#160;seldomly disinfected, 350 citizens were enlisted from the greater San Diego County. In total, these citizen scientists collected 4,080 samples. An online platform was developed to monitor sampling kit delivery and pickup, as well as to collect sample data. The sampling kits were mostly built from supplies available in pandemic-stressed stores. Samples were processed using reagents that were easy to access despite the recurrent supply shortage. The methods used were highly sensitive and resistant to inhibitors that are commonly present in environmental samples. The proposed experimental design and processing methods were successful at engaging numerous citizen scientists who effectively gathered samples from diverse surface areas. The workflow and methods described here are relevant to survey the urban environment for other viruses, which are of public health concern and pose a threat for&#160;future pandemics.

A citizen science project was designed to recruit San Diego residents to collect environmental samples for SARS-CoV-2. A multilingual web-based platform was created for data submission using a user-friendly mobile device interface. A laboratory information management system facilitated the collection of thousands of geographically diverse samples with real-time outcome tracking.

To control community transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the 2020 global pandemic, most countries ...

DNA Virus Detection System Based on RPA-CRISPR/Cas12a-SPM and Deep Learning

We report a fast, easy-to-implement, highly sensitive, sequence-specific, and point-of-care (POC) DNA virus detection system, which combines recombinase polymerase amplification (RPA) and CRISPR/Cas12a system for trace detection of DNA viruses. Target DNA is amplified and recognized by RPA and CRISPR/Cas12a separately, which triggers the collateral cleavage activity of Cas12a that cleaves a fluorophore-quencher labeled DNA reporter and generalizes fluorescence. For POC detection, portable smartphone microscopy is built to take fluorescent images. Besides, deep learning models for binary classification of positive or negative samples, achieving high accuracy, are deployed within the system. Frog virus 3 (FV3, genera Ranavirus, family Iridoviridae) was tested as an example for this DNA virus POC detection system, and the limits of detection (LoD) can achieve 10 aM within 40 min. Without skilled operators and bulky instruments, the portable and miniature RPA-CRISPR/Cas12a-SPM with artificial intelligence (AI) assisted classification shows great potential for POC DNA virus detection and can help prevent the spread of such viruses.

We present a protocol that combines recombinase polymerase amplification with a CRISPR/Cas12a system for trace detection of DNA viruses and builds portable smartphone microscopy with an artificial intelligence-assisted classification for point-of-care DNA virus detection.

We report a fast, easy-to-implement, highly sensitive, sequence-specific, and point-of-care (POC) DNA virus detection system, which combines recombinase ...

Rapid, Safe, and Simple Manual Bedside Nucleic Acid Extraction for the Detection of Virus in Whole Blood Samples

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