Possibility to perform just the gradient run, no injection

Arnvid

<p>Hello.</p><p style="height: 8pt"/><p>I have a question about the possibility to perform just the gradient run without having to inject anything first.</p><p>I am most familiar with Chromeleon software, but for the Acquity we use Empower2, which I am not used to at all.</p><p style="height: 8pt"/><p>In Chromeleon thay call it a "Blank" run, i.e. the gradient starts without injecting anything.</p><p>Is this possible in Empower2? </p><p>If so, how do I do it, is it enough to state 0 for injection volume, or is there another setting for this?</p><p style="height: 8pt"/><p>Regards</p><p>Arnvid Gunnar</p>

AJA

Using Empower

To run the gradient without collecting data select "condition column"

To run the gradient and collect the data chose "inject immediate sample"

RobBurgess

If you select to do a 0µL injection what happens and what do you get?

BerkshireLab

I actually have a question similiar to this post. How would you do that for MassLynx? If I just hit the load button, it just runs the inlet method at the initial conditions. The only way I found to do it is to inject 0 uL, but it still has to puncture a vial and go through the process of injecting.

Also, I'm trying to find a way in MassLynx to set up a column cleaning gradient when I'm not around (i.e. after a run late at night). I have an inlet method associated with my column cleaning, but not a MS Method or a Tune method, so I can't set it up in the sample list. If I set it up in the shutdown as "Load LC Method" and "Run LC Method", will it take it through the full gradient?

EdS

Hi there,

if you use the "Run LC Method" option as part of your shutdown file (as in the screenshot attached), the system will automatically run the full gradient specified in the chosen method without an injection being perfomed.

This will then happen each time the system shuts down.

The best way that I know of to run what is essentially a blank injection in MassLynx (assuming that the purpose of this is for column conditioning...) is as you say to inject from a blank vial at the beginning of the sample list. Whether you inject 0µL or a real injection volume, this will then mimic the run conditions and condition your column.

Hope this helps.

Thanks and all the best,
Ed

BerkshireLab

I do it from the inlet method screen in MassLynx. I first load the method (icon to the far right of the toolbar up top) and then select the icon for "run method" (to the left of the load method icon). When I select this it asks for my injection info, so I just enter the position of my blank vial and enter in 0 uL for amount. You have to have a vial in the position or it won't work. Then the LC basically acts like it's doing an injection (punctures the vial, cleans the needle, etc.) without taking up any of my blank. The LC then runs through the gradient in my inlet method. Basically, it's just like an equilibration/condition because you're not injecting anything into the system. I can't seem to find a way to run a method/gradient without doing an injection of some sorts. I used to use Empower and it was a lot easier!

MassLynx doesn't acquire or save any data since I'm just running the LC through the inlet method, not the sample list (my MS is off and the flow is set to waste). I want to find a way to run it so I can set the instrument up to clean my column after a run when I'm not here (I'm doing it manually in real-time now).

bb

You can do two things:

1. if you want to just do the gradient: Runsamples, function Condition Column. Note: chromatogram will not be stored

2. if you want to just do the gradient and want chromatogram to be stored: Runsamples, Single injection, click Prepare and then Inject

3. if you want to do injection of zero volume: just select Inject samples from Function and key in 0 as injection volume. Sampler will do all operations, but no sample will be withdrawn.

This applies to Acquity, 2690/5, 717+.

Hope this helps