Okay, I suspect I have an issue with the liner seal setup that this injector I believe is a 1079 came with. Originally, there was only an orange o ring that sealed the liner to the septum support and body. It was looking a bit rough so I replaced it with a generic o ring of similar size. Now, thinking about this it would seem that the elastomer would be an obvious source of bleed/contamination.
Consulting the diagram, I see there is supposed to be a graphite ferrule instead. So, I ordered what was supposed to be the correct ferrule, but it does not fit over the liner. Both the liner and ferrule part numbers were straight off Resteks catalog for this machine so I have become properly confused.
Aaannnnddd (because all this confusion wasn’t enough), as of this morning I am now the owner of a Perkin Elmer 2000 ICP-OES!!! Yay more eBay analytical equipment!!! Somebody please stage an intervention for me lol
Yep I’m stupid. Apparently I have an 1177 injector. Not sure how I managed to order the right liners and septa but the wrong liner seals. At least if my new systems come with a 1079, I’ll have at least some of the right parts lol
Wasn’t sure about starting another thread, so I’ll post this here.
I recently got a ~35 year old GC-FID running and it was quite a ride learning all the ins and outs.
Here’s the story:
I saw an ad on Craigslist a few weeks ago for an old HP5790 GC system and went and picked it up, the old guy (90yrs old) was an interesting character who ran soil samples for oil and gas in the 90’s and even discovered a few high output wells here in colorado with it. He included two HP5790’s, a hydrogen generator, zero air generator, air compressor, tons and tons of random GC stuff (truck bed full), as well as a computer with chromeperfect software on it. Hauled all that back to the lab and got it going, before realizing that the floppy disk with chromeperfect on it was left behind (got it a few days later in the mail from him). While waiting to get the disk with the software in the mail, I took a stroll by my local university surplus and saw a few HP5890’s laying around, one with a 7673 autosampler and one with a peaksimple data system attached. I offered the guy $300 for both (helps to have a friend in the surplus department) and walked away a happy customer. I plumbed in the ancillaries that I got from the craigslist deal to the 5890 since it was a newer GC (still from ~1985), and had the peaksimple. After fiddling with the gas pressures for a day and not getting any good results, I removed an aftermarket regulator system from one of the now four GC’s that I have and plumbed it into the chosen one to get better control over gas flows. I still wasn’t getting good results so I plumbed a tube over the outlet of the FID and inverted a graduated cylinder in a tub of water to measure the gas flow by timing how long it took to fill the 10ml graduated cylinder. Once I dialed the carrier (hydrogen) to ~4ml/min, and the FID flow to 40ml/min H2 and ~400ml/min air, I got some good results. It took some time to dial in the oven temp to tease the cannabinoids out but ramping from 200 to 300C over the course of 4 mins gave a pretty good separation. I have a splitless injector on there currently, so I have to inject ~0.1uL to not overload the detector.
Still need to get standards and a good column for it,
although I just got a brand new column on ebay for $40, its a 20m Agilent DB35-MS. Using one of the ten 20yr old shitty columns that I already had, heres what I was able to get from an approximate even mix of CBD, D8, and CBN, its a rough chromatogram, the noise is much smoother now so ill update some of the newer runs shortly, but heres the first one ever:
Yep. This is the part I remember…been more than 10 years since I last beat my head against it. Stock solution was to purchase an HP branded Ethernet card. Which was usually 10x the price.
Has me looking at a FREE GC and wondering about the price of admission…
sure, there is a 0-1V output on these GC, so you can connect a ADS1220+Arduino and have a great 24bits ADC for cheap. i can share source code and wiring if you are interested
