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SONA's test is based on a sample via a nasopharyngeal swab, so not exactly the same as Avacta's direct using saliva. This was confirmed by David Regan, SONA's Strategic Advisor.
Maybe - not sure who distributor will be but you get the point. If they order from Sona then they won't order from someone else. Sons are ahead. They have First mover advantage. Not the end of the world but I can grab my pom poms and start cheering if you think it will change things. Enjoy your walk.
Cytiva are working with Sona?
My view. Boils down to affimers vs antibodies. I guess everyone here is affimers but it is new tech.
If companies are pre-ordering from Sona then i doubt they are also ordering from Cytiva. From that I deduce the S&M teams at Cytiva and Medusa are not yet able to confirm test works. So back to us all waiting on that.
Membrane surfactants and protein binding: good news/bad news
Every nitrocellulose membrane on the market contains a surfactant, usually an anionic surfactant. The exact nature of the surfactant is proprietary for every membrane manufacturer, but the surfactant functions are always the same. First, it makes the membrane hydrophilic. Second, and perhaps even more important, it helps proteins bind to the membrane (Fig 4).
The good news: The surfactant partially denatures proteins dispensed onto the membrane in a buffer and helps them bind to NC fibers.
The bad news: The surfactant denatures proteins. This can potentially destroy the antigen binding sites of some monoclonal antibodies completely, making these reagents unusable in a lateral flow test.
Worth reading both links...
But AS is confident, they would have tested it on membranes before send to Cytiva for diagnostics and FDA submission
Trek
It’s not clear yet. They bind using antibodies or antigens.....sona are using antigens...and they can’t upscale consistently or rapidly.
Process...
“A lateral flow immunoassay, or immunochromatographic assay, is a rapid, convenient test that uses antibodies (or sometimes antigens) to detect specific macromolecules, such as antigens, drug substances, or other proteins.
One of the first steps in lateral flow rapid test development is the selection of the “right” materials, especially the nitrocellulose (NC) membrane. The NC is the heart of the lateral flow test, where the target molecule is bound and where the results are displayed.
A successful lateral flow immunoassay depends on a series of reactions. When selecting materials for immunoassay development, membrane properties and reagent properties must be considered together, as their interactions determine the outcome of test development.”
Full article..(note membrane is key)
https://www.cytivalifesciences.com/en/us/solutions/lab-filtration/knowledge-center/Considerations-for-membrane-selection-for-lateral-flow-immunoassays
the “Company”) is pleased to provide the following update on the development of its rapid-response, Covid-19 antigen test. The Company received confirmation from an independent laboratory that its test achieved a positive response to a recombinant whole spike protein control reagent specific to SARS-CoV2 and matched the limit of detection (LOD) achieved in its own labs. In-house analytical testing has indicated a very high level of specificity to COVID-19, with no false positives being generated.
https://sonanano.com/sona-nanotech-provides-covid-19-antigen-test-progress-update/
Ok here’s why it’s not in the bag....
Further testing will be conducted both in-house and independently using pre-treated viral samples after recent independent testing using virus samples that were de-activated by heat did not provide a response. Exposing a virus to high heat levels can modify its characteristics, making the treated virus sample an inappropriate proxy for a live sample. These findings, coupled with previous hospital-based experiments, have suggested that testing using a live viral culture and/or patient sampling will be required for ultimate confirmation of the effectiveness of the Sona test. The Company expects to confirm further third party validation testing, specific to its device needs, in the near future.
So issues with heat and stability, hence need to move to lab. They basically say between lines you need pcr type test to be sure..
Also from first link, this may also be key to avacta....Cytiva have 3 types of membrane but we don’t know yet if the Affimer is more or less susceptible to binding than the antigen on site. I would suspect that because we can bind to the whole and the detached spike protein that would mean greater sensitivity for Affimer. A guess though....
Next post
Another twitter troll who's claiming to have the inside track on the technical data and being able to compare both tests, Full of s***
Patience is a virtue, good things come to those who wait. GLA, should hear something this week.
Sona in my opinion is barely putting up a fight.... Their test is more expensive, more complicated and uses old antibody style reagents that will hit the same production issues as all antibody derived reagents.
Having said all that they appear to the only true challenge to AVCT's fast, simple low cost test. Unless anyone else has found a better competitor? AVCT's test, if it works, will be hard to beat because if you were to design the perfect test for this current situation you would probably come up with AVCT test.
This is the SONA CEO talking about their test, 13:20mins in he describes how it works. You 'simply' swab your throat, put the swab in a test tube, shake it and then put a few drops on the lateral flow device..
https://youtu.be/HJbWsOJBt1A
Thanks, seems u can't buy it through HL, at least it isn't recognised
The key point, is Sona are not able to produce 'mass screening', this is being able to supply the planet! Avacta's simple test will have the capability to supply the whole world with a test with the results in minutes. BBN also made reference that although SONA has advanced sales they may have issues still.
Avacta will soon have advanced sales too as the distribution team will be working on this now.
Avacta's timing is still not confirmed 100% but is will have scalability like no other and this is the key. But everyday we are getting closer!
Cheers, RK
SNANF
It's Canadian listed. Sona.to
Sona are listed on NASDAQ
What is the market code for SONA? I can't find em on here.
Surely any comments would be opinion Vs opinion.
Check out BBNs Twitter for his a couple of days ago though
...on Twitter, @GTeamjds:
"AVCT is way behind..SONAs test is superior with its GNRs and GEs membrane and adding Bonds digital contract tracing. Sensitivity/specificity optimal levels. Margins high. Cheap...going to HC and FDA. Well known strategic advisors."
Comments?