Re: Where to purchase a solid sampler?
Posted: Sun Jul 03, 2016 6:45 pm
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Where to purchase a solid sampler?
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Re: Where to purchase a solid sampler?
Posted: Sun Jul 03, 2016 6:47 pm
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Re: Where to purchase a solid sampler?
Posted: Sun Jul 03, 2016 7:06 pm
No worries Joe
Thank you for the details - that is really useful
I am also based in the UK -
Your work sounds fascinating. I will need some time to digest and cogitate on it -as will others
If you give me your email - I have a presentation talk that I presented to the RSC using Tenax TA for the analysis of volatiles that I can send you
Kind regards
Ralph
Thank you for the details - that is really useful
I am also based in the UK -
Your work sounds fascinating. I will need some time to digest and cogitate on it -as will others
If you give me your email - I have a presentation talk that I presented to the RSC using Tenax TA for the analysis of volatiles that I can send you
Kind regards
Ralph
Re: Where to purchase a solid sampler?
Posted: Sun Jul 03, 2016 7:09 pm
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Re: Where to purchase a solid sampler?
Posted: Sun Jul 03, 2016 7:14 pm
If you give me your email - I have a presentation talk that I presented to the RSC using Tenax TA for the analysis of volatiles that I can send you
Kind regards
Ralph
Kind regards
Ralph
Re: Where to purchase a solid sampler?
Posted: Sun Jul 03, 2016 7:30 pm
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Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 8:49 am
Hi Joe
Interesting work and quite a challenge. There is a lot of work on ant cuticular hydrocarbons and you have an expert just up the road: Prof Stephen Martin,
Chair in Social Entomology
School of Environment and Life Sciences
The University of Salford
Manchester UK M5 4WT
They use mostly solvent extractions and some SPME, but ants are giants compared to your mites.
Do you really need to work on single mites ? - unless you have evidence that the predators select between individuals your life will be much easier if you take bulk samples from a few hundred or thousand at a time. If your main aim is to identify the cuticular components than you can afford to crud up the inlet with a dirty extract because you only need one good run, even if you need to clean the liner after every sample it might be more cost and time effective than building/buying new hardware. Clean samples will be necessary if you have to run long series of samples to compare between them, but it sounds as if you are not at that stage yet.
Peter
Interesting work and quite a challenge. There is a lot of work on ant cuticular hydrocarbons and you have an expert just up the road: Prof Stephen Martin,
Chair in Social Entomology
School of Environment and Life Sciences
The University of Salford
Manchester UK M5 4WT
They use mostly solvent extractions and some SPME, but ants are giants compared to your mites.
Do you really need to work on single mites ? - unless you have evidence that the predators select between individuals your life will be much easier if you take bulk samples from a few hundred or thousand at a time. If your main aim is to identify the cuticular components than you can afford to crud up the inlet with a dirty extract because you only need one good run, even if you need to clean the liner after every sample it might be more cost and time effective than building/buying new hardware. Clean samples will be necessary if you have to run long series of samples to compare between them, but it sounds as if you are not at that stage yet.
Peter
Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 10:22 am
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Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 12:30 pm
Hi Joe
How about if you bury a SPME fibre in 1000 mites ? Cuticle compounds are probably high MW so it will take ages to equilibriate, but it might work.
Another possibility is to put mites into the sealed end of a narrow glass tube, put a little bit of glass wool on to to stop them moving around, suck the air out and then flame seal the other end. Put the mite-free end into a freezinf mix, and heat the mites with a hot air gun. Cuticle volatiles will collect at the cold end.
I wouldn't worry about the green colour of extracts, there are bound to be some non-volatiles in any crude extract, whether they are coloured or not makes no odds. What you have there is actually cleaner than most of what I inject (presuming you are going to filter out the carcases !!). To do the identifications you need one good chromatogam with clearly separated peaks - if that cruds up the liner it will have been worth it. If you are worried about the column then put in a guard column.
You are probably doing it already - but you absolutely must show that the extracts or SPME fibers contain the active ingredients by testing them on the predators before you bother to analyse them.
Peter
How about if you bury a SPME fibre in 1000 mites ? Cuticle compounds are probably high MW so it will take ages to equilibriate, but it might work.
Another possibility is to put mites into the sealed end of a narrow glass tube, put a little bit of glass wool on to to stop them moving around, suck the air out and then flame seal the other end. Put the mite-free end into a freezinf mix, and heat the mites with a hot air gun. Cuticle volatiles will collect at the cold end.
I wouldn't worry about the green colour of extracts, there are bound to be some non-volatiles in any crude extract, whether they are coloured or not makes no odds. What you have there is actually cleaner than most of what I inject (presuming you are going to filter out the carcases !!). To do the identifications you need one good chromatogam with clearly separated peaks - if that cruds up the liner it will have been worth it. If you are worried about the column then put in a guard column.
You are probably doing it already - but you absolutely must show that the extracts or SPME fibers contain the active ingredients by testing them on the predators before you bother to analyse them.
Peter
Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 1:58 pm
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Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 2:41 pm
Hi Joe
This is really interesting.
You have found that your solvent extracts have biological activity.
1. I am sure that the chromatography side can be sorted.
2. I have one idea for your low/non - volatile compounds
Because I know that it sounds crazy I have pondered a while whether or not to post it.
If you separated your extract on a TLC plate then allowed the mites to scamper across the the plate and see if they are drawn to or repelled by certain areas.
Release the mites!
If so those spots can be further analysed - I know it sounds stupid but perhaps?
Regards
Ralph
This is really interesting.
You have found that your solvent extracts have biological activity.
1. I am sure that the chromatography side can be sorted.
2. I have one idea for your low/non - volatile compounds
Because I know that it sounds crazy I have pondered a while whether or not to post it.
If you separated your extract on a TLC plate then allowed the mites to scamper across the the plate and see if they are drawn to or repelled by certain areas.
Release the mites!
If so those spots can be further analysed - I know it sounds stupid but perhaps?
Regards
Ralph
Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 3:15 pm
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Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 4:46 pm
Hi Joe
I have to admit that it is a long time since I made my own TLC plates.
You have some experience in TLC, which is good
Now one can buy pre-prepared micro TLC plates in silica or alumina.
We can discuss it further on the forum but It is just a question of constructing a micro TLC chamber with a beaker and applying your extract to the plate and using a suitable solvent system similar to your extraction solvent (what was that?)
I also thought that it could be used for applying and separating anti microbial compounds from a leaf or plant extract then spraying micro-organisms onto the plate and seeing where the micro-organisms were repressed/killed
I still think that it is a crazy idea
We are now going back to the origins of chromatography
Regards
Ralph
I have to admit that it is a long time since I made my own TLC plates.
You have some experience in TLC, which is good
Now one can buy pre-prepared micro TLC plates in silica or alumina.
We can discuss it further on the forum but It is just a question of constructing a micro TLC chamber with a beaker and applying your extract to the plate and using a suitable solvent system similar to your extraction solvent (what was that?)
I also thought that it could be used for applying and separating anti microbial compounds from a leaf or plant extract then spraying micro-organisms onto the plate and seeing where the micro-organisms were repressed/killed
I still think that it is a crazy idea
We are now going back to the origins of chromatography
Regards
Ralph
Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 5:49 pm
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Re: Where to purchase a solid sampler?
Posted: Mon Jul 04, 2016 6:01 pm
Ralph, that TLC plan is brilliant - antibiotic assays upscaled from microbes to mites !
Joe - why not do the SPME with live mites - they will stir themselves and rub their cuticles on the fibre.
If the peaks from the extract are too small you could concentrate it by evaporation.
Peter
Joe - why not do the SPME with live mites - they will stir themselves and rub their cuticles on the fibre.
If the peaks from the extract are too small you could concentrate it by evaporation.
Peter