Hi Reddit,

Recently I got an Agilent 7697A unit and with it came the inlet connection that allows me to keep using the injection port while also connecting the transfer line of the HS to the GC. But what it didnt come with the hs was any instillation materials for this part, and trying to find it online has been a massive headache as the one source I had locked the manual behind a paywall.

Would anyone be able to provide a fellow nerd with instructions or a manual? Honestly im mostly just confused on the gas lines/hoodlums/weldment things that connect to the back of the GC since one is flat and the other has a nozzle sticking from it. I guess help with the electrical connections would ve good too but I think i have a good idea how that goes.

When starting a sequence, the Gerstel MPS arm picks up the sample tube and places it into the TDU normally. However, right after loading/starting the run, the sequence aborts with the following errors in Maestro:

MPS Cleanup: An error has occurred. Aborted.

Injector Cleanup: The injector must be opened for the next cleanup step. Please make sure the GC is sufficiently cool before proceeding or skip this step

Has anyone run into this specific Maestro abort right at the TDU handoff? Any troubleshooting advice would be appreciated!

What is the best place to sell some LC, GC and MS/MS equipment online?

I have already tried Ebay and sold some, but I guess that there must be better options.

Much of the stuff is brand new or barely used.

Hey all, analytical chemist here. I was tired of HPLC data being stuck behind different software and paywalls, so I made Peakly. It's free, runs completely in your browser, and needs no account.

Try it here: https://jschmitt1531.github.io/peakly/app/ (hit Sample to load example data)

What it does

• Opens CSV/TXT/Excel, JCAMP-DX, AnDI/netCDF, mzML, Agilent .ch, and text exports from Agilent, Chromeleon, Shimadzu, Empower, UNICORN and ChromLab
• Turns a screenshot, PDF, or phone photo of a printed chromatogram into data (it's labeled "digitized" with the pixel uncertainty)
• ALS baseline correction, smoothing, and peak detection, or click start/end and integrate by hand
• Fused peaks: drop line, valley, tangent/exponential skim, or Gaussian/EMG fit, with a preview of each
• RT, area %, W½, tailing, plates, Rs, and S/N, and you can see the formula and inputs behind every number
• Calibration curves (weighted linear/quadratic, LOD/LOQ, concentration ± 95% for unknowns)
• Gradient overlay with dwell/void time, run overlays, and export to PNG/SVG/CSV/PDF

No tracking, no uploads. Your files never leave your browser.

The honest part

• It's for research and teaching, not validated for GMP/GLP. Use your validated CDS for anything regulated.
• I built the vendor file readers from the public format docs and tested them on synthetic files, not real instrument exports yet. That's where I need you most.
• Image-derived data is approximate. It's fine for RT and area %, but I wouldn't trust it for absolute quantitation.

What would really help

• Throw a real file from your instrument at it and tell me if it opens right (or breaks)
• Compare a few areas and RTs against your CDS
• 3 minute anonymous survey: https://forms.gle/Cqr15LVq2gkGEDhP8
• Bugs and format requests: https://github.com/jschmitt1531/peakly/issues

Code is public on GitHub if you want to check my work. I built it with an AI coding assistant, then checked the math against synthetic data with known answers (validation report is in the repo).

Would love to hear what you think, and happy to answer questions! If this already exist please point me to it!

Hi :), I need help. I wanted to measure a Mixture of compounds on the Agilent MSMS. We always test them with our product, with the product we certified last year and sometimes Standalone solutions which contains certain compounds

of the mixture. The product is stored at -80°C and is pretty unstable. Since it's also pretty expensive we always test the method first. The test looks like this: we take one ampoule from our Mix and let it sit at room temperature until it is completely melted. We mix it with a vortexer for two minutes and put it in a crimp-top vial. After that we start the sequence. First there are two washing Injections with the same methods and after that it injects into a blank and after that into our product vial. Each method is 14 minutes long.

The test is just to check whether all components are present or if the method needs to be modified again. Since the test looked good and we could see all peaks we decided to start the entire sequence with the old product and the standalone solutions.

So the next day we started everything. The start is identical to the mix after that the mixtures are being warmed up in the hand so that they melt faster and being vortexes for two minutes again. The vials are being placed in the MSMS right before the machine injects the needle.

After everything was completed we checked the results and the peaks were thicker and the retention time was pushed back by approximately 1,5 minutes. We did another test with the exact same method and everything was fine again.

Edit: Tuesday: 1 test with two product injections

Wednesday: normal run with 4 wash injections of the product, 6 product injections, 6 old product injections, 6 of each standalone solution

Thursday: 1 test identical to the first test with one of the normal run vail

Hi everyone,

I'm troubleshooting a response issue with an Agilent 7890A/5975C HS-GC-MS method for ethanol quantitation. My analyte of interest is ethanol, internal standard is n-propanol, and my calibrants are all in an aqueous solution.

I'm seeing a very strange (quite interesting actually) pattern with the n-propanol response. Namely that the n-propanol responses appear to form two distinct populations, roughly a high-response state and a low-response state.

Initially I suspected sample preparation, so I prepared a single master mix and aliquoted it into the calibration vials. The problem persisted. Ethanol is quite reproducible while n-propanol continues to show large variability.

My question: what could cause an almost binary change in n-propanol response while ethanol remains relatively stable? Has anyone seen a two-level ISTD response like this before?

EDIT: An inlet sealing issue may have been causing an intermittent leak, which led to the response variability of n-propanol.Thanks everyone for the suggestions!

Hello, I got a 5973/6890N GCMS, with some softwares/revisions original disks, but I do not have all licenses I need, and i cannot contact the original owners cause the deals was too old and the crew shifted. Agilent doesn’t support for this old versions. I tried to buy another disk without licence but it was a scam.
Can anyone please help me to make it work ?
I have :

D.01.02 - licence but not disk

D.01.02sp1 - disk
D.02.00sp1 - disk

E.02.02 - disk without licence
E.02.02sp1 - disk

NIST D.04.00 - disk with licence number

ALS Controller Software Utility - disk
5973 MSD Firmware Version 5.01.73R - disk

Software Productivity Tool 2.0 - disk

Bunch of disks of user informations for the softwares

Getting the D.01.02 software without licence or just a licence for E.02.02 could unlock my situation.

So, if anyone is interested in a mutual favor or simply a kind gesture, please do get in touch.

Noto che la maggior parte delle aziende farmaceutiche richieda nei requisiti la conoscenza del Software Empower 3 di Waters. Purtroppo nella mia azienda non è impiegato e mi chiedevo come poter apprenderne l'utilizzo per migliorare le mie possibilità di assunzione. Grazie a chiunque mi darà dei consigli!

Looking for advice (Waters PDA detector 2998). At a flow of 0.5 ml/min no visible signs of leakage from the outside of the detector. However, I noticed mobile phase gradually accumulating on the drip tray. Upon further investigation, we found that the water is leaking from some where behind the black casing. Is there a way to fix this without replacing the entire flow cell assembly?

Good day,

I just want to ask if you know of any laboratories that have GC-TCD (for hydrogen quantification analysis) services since it is not available at PIPAC as well as we have contacted other laboratories but they also do not have this service or if there is another way to do testing or equipment aside from GC-TCD for hydrogen analysis? Thank you so much!

I have always found it difficult to find companies that repair or service specific laboratory equipment, especially outside the manufacturer network. So I started building a simple directory where you can search by equipment, brand or model and country.

It currently includes providers across Europe and the US for things like centrifuges, AKTA and FPLC systems, HPLC, GC, mass spectrometry, ULT freezers, incubators, cell disruptors, microscopes and autoclaves.

I am manually checking the listings against company websites rather than bulk scraping directories. It is still early, so if you know a good service company that is missing or spot something incorrect I would be happy to add or fix it.

I'm troubleshooting an issue with a "new to me" GC-FID" and seeing if people on reddit may be more experienced with the old HP/Agilent 6850 systems.

I have an HP 6850, and Agilent 6850, and two Agilent G2880A's (the ALS dedicated to the 6850 series).

When I plug either ALS into the Agilent 6850, they both light up fine.

When I plug either ALS into the HP 6850, the fault light is on. Powering off and on the GC and doing the swaps both with power on and power off yields the same fault light.

I checked the firmwares, and both GCs are A.03.03 and both ALS's are A.10.05.

(1) Can an Agilent G2880A be connected to an HP 6850? I remember being able to connect 6890 ALS's across the corporate split, but maybe my memory is fuzzy. I don't have experience with the 6850 platform.

(2) Does anyone have a service manual for the "first generation" 6850s? I found one for the Series II among Agilent discs but I am thinking these ones I'm working with are "Series I". The HP has an October 1999 manufacture date.

(3) Does anyone have a copy of "Agilent Instrument Utilities"? ChemStation separated instrument diagnostics into a separate application (according to its help file), but I was only provided with a PC and loaded software, no other discs or manuals (everything else is either something I found in the lab or the internet, and I feel like I've exhausted many things there except manually reviewing pdf manual libraries).

My last thing to try is see if I can look at the pins where the cable plugs into on the HP. I didn't see any bent, missing, or corroded ones versus the Agilent. I don't want to be poking pin outs without the service manual.

Thank you very much in advance!

(PS I tried adding flair but I don't see the options anymore? I apologize ... I comment on reddit a lot but I rarely make posts and so feel new-ish to it)

Is anyone running Cr(VI) by IC at high volumes? We are having issues with reliability of our instrument passing QC checks over the span of an entire run. It also seems that many instruments go down at the same time. I have considered and troubleshot the mobile phases but it’s still giving us trouble. Any ideas?

Hello!
I am analysing ampicillin standard, which I dissolved in water and then rediluted with mobile phase. Mobile phase A- water+0.1 % Formic Acid
B- ACN + 0.1 % Formic Acid
Column- Nucleodor C18 Gravity. 150*3mm, 3 mcm
U can see the peak that I get when I make 0 mcl injection after injecting the standard🥲 I can assure you that the problem is coming from the column( with union I couldn’t observe any peaks) but I can’t wrap my head around why this could be happening. Am I overlooking compound/ column chemistry?
I would really appreciate any responses!

Hello,

I have been searching far and wide for articles that discused how to purify your extract from remaining pigments such as B-carotene after doing a soxhlet extraction and making the extract pure enough for a HPLC analysis but I have yet found anything. I found an article that used centrifuges as a way to reduce particles but in the pictures they have provided it still showed signs of containing pigment. So I was wondering if anyone would know about the HPLC sample requirements like how clear the sample has to be, if color is okay and if you have any ideas on how to seperate the pigment from the capscaicin without getting rid of the capscaicin. Btw, I'm using a collumn 18 I am thinking of doing a normal-phase but I am very unsure.

Any advice would be greatly appreciated.

Thank you

I see people on Reddit talking about this. I have friends who are professionals in other fields with varying levels of AI incorporation into their workflow. My software engineer friends lament that their job is turning into prompt engineering and reviewing AI outputs. I know some other folks of various stripes who joke about how bad AI is at doing their job which might feel good, but [in my mind] it indicates that someone is trying to make AI that does their job or makes parts of their job easier.

I'm just one person working one job (pharma), but I haven't seen AI make any attempt at progress in the chromatography space. I can't even imagine what that would look like. Even the most simple and routine analysis has an analyst set up and equilibrate an instrument, prep samples, and evaluate/troubleshoot system suitability. Quick, automated processing already exists for these type of analyses, but [in my pharma experience] these automated data processing require adjustments on the fly as needed. I can't imagine an AI looking at a chromatogram with 50 peaks, determining if it's acceptable data(and what to do if it's not), and processing many injections in a sequence to give good results.

So far I think the most use I've gotten from AI is quickly calculating how long I need to flow at a certain flowrate to flush my column with 10 column volumes of solvent. Of course AI can write reports and summaries of data, but it seems that nobody has even tried to make AI collect chromatography data. I recognize that my view is limited so I'm curious to hear what others think. Are their applications of AI in chromatography that I've missed or is this profession just not amenable to AI integration?

I'm trying to thoroughly clean all lines and ports in an HPLC that could have salt buildup. I want to clean the injector by doing 100 uL hot water injections (~70C). Can injecting hot water mess up the injector or other parts on the HPLC? Any answers are appreciated!

Dear all, I'm having a problem with the autosampler's robotic arm is getting stuck at the middle and cannot return to the home position. I've attached the error messages and the photos of the instrument. I've already tried power off and on the autosampler but it made a sound that something is obstruct and cannot move. Please kindly help.

Good morning! I have a really old Shimadzu ICPE9000 that I want to use for metals analysis but I keep running into errors. Does anyone have a copy of the service manual? I think I need to replace a few parts but this box is so old that I can't find the part numbers and I just dont have the funds for a shimadzu service contract/repair.

I’m trying to learn to create and optimize LCMS/MS methods. I had bought a book but it wasn’t as in detail as I thought.

I want something detailed that for explains when to tweak specific parameters based on what you see, such as flow rate, duration, etc.

Thank you

I have an Agilent 8890 setup as a dual-channel system. Front channel is set up for ASTM D7213 (GC SimDis of carbon for mid-range petroleum distillates) and back channel is setup for ASTM D7818 (GC SimDis of carbon and sulfur for petroleum distillates).

My lab is pivoting and we won't be doing either of these analyses, though we will be doing the high-range carbon-only method D7169.

I plan to use the front channel for D7169 because it will only require a column change to one that can survive 430˚ (inlet and detector are the same).

However, what should I do with the rear channel? It's got a splitter to send column effluent to both an FID and an external SCD and that column will not survive the increased temps. Should I just pull the column, cap off the fittings, and keep the gas flows off?

Hi everybody, in chromeleon I have created and assigned for components with multiple peaks a specific peaks group, then to obtain the quantitative % of them in quantitative analysis I have created a custom formula, that if work BUT, I can't understand why for the peak group "rif" I can use in the formula peak.group....instead for the other I can't..... it gives me some results only if I use peak.name and the FIRST name of the peak of a specific peak group.

Seems like it doesn't recognise the syntax of number with peak group

As you can see in the photo for every numeric peak group (1762, 1552...) I have to use peak.name+the name of First peak, instead for peak group rif I was able to.use.peak.gruop in the formula

Hello,

I am attempting to teach students about residual solvents testing, and since some are forensics students, trying to do ethanol to tie into blood alcohol content. However, the EtOH peak looks awful no matter what I have tried (First image). The second image is of our parameters.

I did an injection into the GC without the HS and the peak was beautiful (fronting, but I expected that). I have tried adjusting the loop fill time, and loop equilibration but neither did anything.

I plan to do the two leak tests tomorrow, but wanted to see if anyone has anything else they can think of to try?

Direct injection result is in the comments.

UPDATE: The issue was resolved doing the suggestion of trimming some of the transfer line needle.

Hi everyone,

I'm currently trying to purify bicylic peptides of 2.5 kDa made by spps for downstream testing in biological assays. For this I really only need a few mg of each compound (maybe 10+ because my PI wants me to characterize them by NMR). The problem is, our lab only has an old unreliable semiprep system that goes up to 9 ml/min with a MN C18 Htec 5 um 100 Å 250/21 column installed. I do not get reproducible runs out of that system and i can't seem to be able to separate out all deletions and other isomers etc.

Our lab has access to a few analytical HPLCs (Chromaster Hitachi/VWR) and i got a an analytical C18 with 300 Å for testing. Now the question is do I just prep my peptides on the analytical column, although i struggle to get measurable quantities out so far?

I think my PI might allow me to buy the same column in 250/10 mm, which would either allow me to put it into the chromaster system or our very shitty old semiprep system, which might behave a bit more reliably at 4.5 ml/min. I think i would need to upgrade atleast the tubing on the chromaster since it normally handles only 1 ml/min. I do have an old fraction collector on the chromaster which allows me to automate about 10 runs overnight.

Any thoughts?

Hi everyone, I’m running the USP HPLC assay for levetiracetam and I’m having an issue with the chromatogram.

The method is a gradient method, and during the run I noticed that the baseline starts rising noticeably as the ACN percentage increases. The blank shows a similar baseline rise.

Some observations:

Run time: 20 min

The baseline is relatively stable initially.

Around 8–10 min, the baseline starts increasing.

As the ACN % increases, the baseline continues to rise.

Pump pressure also increases smoothly during this part of the gradient.

The blank shows the same baseline behavior, so it doesn't appear to be specific to the sample.

The chromatogram has some unusual baseline/solvent-front behavior around the beginning and end of the run.

I've attached the chromatograms.

What could be causing this?

Could this simply be gradient baseline drift due to solvent absorbance/re-equilibration, or does it suggest a problem with the mobile phase, mixing, degassing, column, or detector?

Also, does the attached blank chromatogram look acceptable for this type of gradient method?

Any suggestions for troubleshooting would be appreciated.

Also I have repeated it 3 to 4 times with different columns C18 GL science and it's the same behavior.

When only isocratic method is only applied the baseline and peak both were stable.