London South East prides itself on its community spirit, and in order to keep the chat section problem free, we ask all members to follow these simple rules. In these rules, we refer to ourselves as "we", "us", "our". The user of the website is referred to as "you" and "your".
By posting on our share chat boards you are agreeing to the following:
The IP address of all posts is recorded to aid in enforcing these conditions. As a user you agree to any information you have entered being stored in a database. You agree that we have the right to remove, edit, move or close any topic or board at any time should we see fit. You agree that we have the right to remove any post without notice. You agree that we have the right to suspend your account without notice.
Please note some users may not behave properly and may post content that is misleading, untrue or offensive.
It is not possible for us to fully monitor all content all of the time but where we have actually received notice of any content that is potentially misleading, untrue, offensive, unlawful, infringes third party rights or is potentially in breach of these terms and conditions, then we will review such content, decide whether to remove it from this website and act accordingly.
Premium Members are members that have a premium subscription with London South East and have access to Premium Chat. You can subscribe here.
London South East does not endorse such members, and posts should not be construed as advice and represent the opinions of the authors, not those of London South East Ltd, or its affiliates.
Thanks Trek for your most interesting discussion (with references) about digitisation of LFD's. I had no idea of this sort of thing & learned a lot! I admit I will have to read your post + the refs again with a fresh mind tmoz!! Just enjoyed a nice take-away meal with the Mrs this evening with too much good Rioja so my mental state is not in top form at the moment. I'll sleep well tonight dreaming of Avacta SP in 2 months.
was going to have a rant Taverham but that was funny so I'll let you off!
dave, our CEO has certainly over delivered when it comes to time scales- fully funded until 2021 - he beat that and made it 2020 !
Still stand by £3 Monday at 8am am thinking about a charity trek
The placing was over subscribed and successful I think it shows the direction this share is heading!! Hoping for transformational news in the not too distant future soon!! Cant be long before we see £5+ here!!!
nice one hants
I've just worked it out... 7pm... that's why you're called sleepydave, right?
Sleepydave, great post!
But 7pm? Are you having a lie in?
I agree it's probably inconceivable. Firstly, because I'm sure II's taking large holdings would have wanted some assurances. Secondly, raising £40m which is partly/largely for the purpose of bringing the test to market and then immediately failing would destroy the credibility of both the CEO and the company as people would assume they knew it was going south and just wanted to capitalise before they told anybody.
Well we know that our CEO recently has underpromised and over delivered when it comes to timescales.
Specifically re the LFD test we were told on the 15th May that its development was proceeding apace. Its in my mind although I haven't double checked that he was expecting data to start coming back to him from Cytiva end of May/start of June. If I'm not wrong in that then standing the terms of the placing RNS I would submit its inconceivable that ;
1. The data is not flowing (see what I did!) and
2. The Data is not good
There will be a huge amount of legal and technical work going on to accredit the test and as discussed by others work out
the recommended procedures for self testing which need to be spot on and as uncomplicated as possible.
Probably entirely irrelevant but I see the instructions for the Atlas Medical Saliva Alcohol Test Strip give you 2 uncomplicated choices. Either saturate the "reaction pad" with saliva from the "collection cup" or apply saliva directly to the pad. Sometimes less is more. Even more irrelevent if the above test is positive it has to be followed by a second analytical test the preferred method being Gas Chromatography (shout out for Mass Spectrometers?)
Anyway I'm rambling.
Great posting today guys and gals and see you all Monday 7pm sharp!
Trek, regarding 'spitting into a straw', I haven't seen the video but I'm guessing that is actually a pipette - basically a sqeezable tube that allows you to direct the sample onto a specific spot after it's been collected.
Used in some drug testing kits.
The test is to detect amylase as a marker for saliva - but the principles remain the same.
Sorry, had to go for tea and did not finish post - this is from a lateral flow test kit.
RSID™-Saliva Buffer components
The RSID™-Saliva laboratory kit includes extraction buffer (25 ml) and running buffer
(5 ml) that is required for use with the RSID™-Saliva kit. Each experiment included in
this validation document uses RSID™-Saliva extraction buffer for extraction of the
sample/s (extraction volumes are specified); the final volume of the sample to be tested
is brought to 100 µl with RSID™-Saliva running buffer. RSID™-Saliva extraction buffer
+ RSID™-Saliva running buffer (100 µl) is loaded onto the cassette and results are
recorded after 10 minutes.
RSID™-Saliva extraction buffer is designed to efficiently extract the protein a
amylase from questioned stains and swabs. RSID™-Saliva running buffer is designed
to dissolve the antibody-colloidal gold conjugate from the conjugate pad, maintain an
extract at the appropriate pH, and facilitate correct running of the test. Components of
the extraction and running buffer include buffer and salts (Tris, NaCl, KCl) for
physiological stability, a chelating agent (EDTA) for stability, detergents and surfactants
(Triton X-100 and Tween 20) for extraction efficiency and solubility maintenance,
protein (BSA) for reducing non-specific adsorption and loss, and a preservative (sodium
Re your first question, I did see a video of spitting into a straw (can’t find link now) and thought what’s the point of that! Just as well dribble onto the collection membrane and that’s my guess as to how saliva will be collected.
The second question is very interesting. From as far back as 2018 Sona have been working with bond on how to digitalise LFD readouts. This can be via Bluetooth to phone to cloud or by remote collection device. I do think though that that will be second generation stuff. We/they will just deliver a simple binary test but there are massive technological opportunities.
Here’s an example..
# Buy test from Medusa 19. Name, address and email registration. State if for third part e.g elderly relative.
# Comes with serial number and chemical power transmitter that operates when package is opened.
# Pair mobile with device.
# Perform test.
# Results are up-loaded to cloud and results emailed back with unique SN.
# Test is valid for say 14 days, log on to theatre and book your seat.
All pretty sci-fi!
Sona vid 1 min in linking with Bond 2018
Qiagen have a device that kind of explains the above..
“Powerful combination of detection technology, design and comprehensive Studio Software. Learn more about our customizable solution for your quantitative lateral flow assay.”
Even as far back as 2015 smartphone tech was recognised.
Lateral flow immunoassays provide low cost, fast, portable and simple to use devices, with yes/no answers seen by the naked eye, .... These devices are fully automated and equipped with a high resolution camera, a powerful processor with high storage capacity, wireless connectivity, real-time geo-tagging, secure data management, and cloud computing.” Etc
You see we can only begin to imagine the permutations and applications of this new technology and imo what we get ‘next week’ will be a hammer to hit the virus. What potentially will follow could be an inbuilt smartphone test track and trace technology using the phones contacts and cloud based computing.
I do have experience of working with high end tech in telecoms. Trust me the tech is ‘easy’. It’s the ethics and regulatory hoops that are the difficult part but that is even more so evident in AS’s field so he will be well aware.
Avacta limited only by your imagination!
'Patients were asked to pool saliva in their mouth for 1-2 minutes prior to collection, and gently spit 1-2 mL', this gave 85% positive compared to nasal swab.
I have seen a MS study that used a saline gargle. One report indicated that sampling from back of the throat (essentially gargling) was better
This one looks more sophisticated actual pregnancy test !!!
Seems sensible at first sight, Phantom 25. There will be considerable intra-individual variation in viscosity and hence flow characteristics of saliva samples.
I did read a Cytiva doc than said in some circumstances the saliva has to be mixed with fluid to make it flow better, but cant locate it now
Flyingmachine - thanks for your take on this. You make sensible and realistic comments, and I say that without in any way trying to appear patronising.
I simply hope that end-user sample collection does not compromise our progress in any way whatsoever, whatever is decided.
Stanman, it is an interesting question that I have also pondered over recently. For me, it is preferable for collection to be taken by swabbing inside of the mouth and/or placing in the mouth for a short period of time (as in the video), rather than someone spitting/spilling saliva into a small pot on the device, or a collection pot which you pour onto the device. Spitting or spilling saliva onto the device from your mouth is not condusive to a safe testing environment, which is important for populous areas like airports and other busy meeting points. Collection from within the mouth is preferable but the demo video spent about 5 mins going through what to do and what not to do so really not as simple as one would think at first thought and room for user error. Also, the test for alcohol and drugs probably require less sensitivity than for particles of a virus. So it will be interesting to see what they come up with in order to collect enough viral capture.
Stanman, 2 great questions but probably lost in the noise on this board. I do think the capture of the saliva sample is key. There will have to be some very clear instructions to do it in a controlled way that provides the best possible sensitivity.
I think 13thmonkey is right regarding the results capture. I think the gov will look to incorporate approved consumer tests quickly into their strategy and using technology such as QR codes and an app is the way. I feel the gov can catch up with Avacta on this front though rather than worry about it now.
Thanks to those who responded to the questions!
If the LFD is going to be marketed directly to end users, and that seems to be the case, rest assured that regulatory authorities will take great interest in checking out the propensity for end user errors that might give rise to an incorrect result.
Hence the reason for my posing the question about the process of sample collection.
The video about the Oratect slide was interesting and although this slide is more complex in that it tests for multiple analytes, there is obviously plenty that can go wrong and the commentary simply keeps saying if the checks and balances at any stage indicate it's not working the test slide in use should be discarded and a new one tried again.
It is unlikely that say at £25 a go, an end user will have an unlimited supply of slides to keep trying until they get it right and so will be very tempted to simply to "make do".
I will be very interested to see what the approach of Avacta/Cytiva is to this seemingly simple side of things - it is a pity there is no opportunity for us to ask Alastair about this.
In the civil engineering industry, the tier 1 contractors test us for drugs as part of the site induction when you start on a project, as well as periodic random testing of the whole workforce and after dangerous occurrences or reason to believe. The site that I was on prior to this pandemic uses a system similar to the one pictured in the link below. Basically you suck and chew the stiff cotton like swab until it goes soft, place it into another part of the kit that looks like the outside body of a syringe and push down to expel the saliva from the nozzle. You drip a little bit onto the little receptor holes that you can see on the cassette and then wait a couple of minutes to see which bars appear on the little lcd like panels within the cassette.
Thanks for that video.. 2minutes in... very graphic indeed!
example how to collect saliva direct from mouth https://www.bing.com/videos/search?q=how+do+apply+saliva+into+lateral+flow+device+method&&view=detail&mid=893F8807A71D72C0FBEF893F8807A71D72C0FBEF&&FORM=VRDGAR&ru=%2Fvideos%2Fsearch%3Fq%3Dhow%2Bdo%2Bapply%2Bsaliva%2Binto%2Blateral%2Bflow%2Bdevice%2Bmethod%26qpvt%3Dhow%2Bdo%2Bapply%2Bsaliva%2Binto%2Blateral%2Bflow%2Bdevice%2Bmethod%26FORM%3DVDRE