Can’t draw peptide through filter…

[PunkN]

Losing my mind here. I just made a fresh batch of tirz30. Trying to filter it and it will not pull into the syringe. I just wasted 4 filters, 2 luer lock syringes and like 6 damn needles.

Exasperated. Nothing I googled helped. What can I doooooo?????

 

[randompersonrandom]

uh...if you can't get it into the syringe, and there's a filter involved, then that may be your problem. You pull into the syringe with no filter. Then you put the filter on with a fresh needle and push into the vial or cart.

 

[PunkN]

OMG. I’ve done this before and now I feel like an idiot. In my defense my doctor is adjusting my thyroid medicine and it makes me feel like a loon and unable to concentrate.

 

[randompersonrandom]

OMG. I’ve done this before and now I feel like an idiot. In my defense my doctor is adjusting my thyroid medicine and it makes me feel like a loon and unable to concentrate.

Hey, no worries--least you gave a clear enough description of your workflow that it was easy to ID the part that sounded funky!

 

[PunkN]

I am a mnemonic learner so I’ll just remember filtering is ‘exit only’.

 

[randompersonrandom]

I am a mnemonic learner so I’ll just remember filtering is ‘exit only’.

I mean, if nothing else, now we have a clear answer to "why don't we filter INTO the syringe instead of OUT of the syringe? If we used a fresh syringe, would it even matter?" Cause it'd be harder to draw the pep IN than push OUT.

(someone will pipe up and say "Because we want the filter to be the LAST thing it passes through so we get out every single little bacteria!" to which I say pipe down or I'll steal your lunch money, nerd)

 

[FilterOrDeath]

I mean, if nothing else, now we have a clear answer to "why don't we filter INTO the syringe instead of OUT of the syringe? If we used a fresh syringe, would it even matter?" Cause it'd be harder to draw the pep IN than push OUT.

(someone will pipe up and say "Because we want the filter to be the LAST thing it passes through so we get out every single little bacteria!" to which I say pipe down or I'll steal your lunch money, nerd)

The lunch money comment made me laugh harder than it should have! And I wanted to explain why it was so difficult to try and use the filter that way. The syringe filters we are using are unidirectional so it was doing it's job to prevent someone from pulling fluid back through the filter into the syringe. For most syringe filtering including sterilization we want the unidirectional filters. There are some fancy bidirectional syringe filters out that pull in liquid easily. But I've never had a need to use one of those.

 

[randompersonrandom]

And I wanted to explain why it was so difficult to try and use the filter that way. The syringe filters we are using are unidirectional so it was doing it's job to prevent someone from pulling fluid back through the filter into the syringe. For most syringe filtering including sterilization we want the unidirectional filters. There are some fancy bidirectional syringe filters out that pull in liquid easily. But I've never had a need to use one of those.

Ok, your lunch money is safe, because that IS interesting. I was back of my head thinking "Funny that the vacuum of the syringe isn't enough to pull the liquid through but the push of the syringe is, I thought the vacuum would be stronger than that" but it's neat to know that it's not that, it's that stuff doesn't go through that way.

 

[miss-sanne]

I had the same problem, because my syringe was a 5 ml.

When I switched to 2 ml, it was easy, because of smaller diameter.

 

[Turbo-Farmer]

I was going to try drawing through the filter into the syringe. I guess I’ll skip that one. Does seems like it would be nice to have the option. But I figured it couldn’t be that easy.

The undirectional part didn’t occur to me.

I do think you can apply more force pushing the plunger than you can pulling. Direct force vs vacuum.

 

[miss-sanne]

I was going to try drawing through the filter into the syringe. I guess I’ll skip that one. Does seems like it would be nice to have the option. But I figured it couldn’t be that easy.

The undirectional part didn’t occur to me.

I do think you can apply more force pushing the plunger than you can pulling. Direct force vs vacuum.

I tried that, lol. I don't need to filter twice, and it was also impossible.

These days, I don't filter, because no matter how I do it, I end up spilling a lot.

 

[Retazempic]

I mean, if nothing else, now we have a clear answer to "why don't we filter INTO the syringe instead of OUT of the syringe? If we used a fresh syringe, would it even matter?" Cause it'd be harder to draw the pep IN than push OUT.

(someone will pipe up and say "Because we want the filter to be the LAST thing it passes through so we get out every single little bacteria!" to which I say pipe down or I'll steal your lunch money, nerd)

I had that same question. When I think filter, I always conceptualise a coffee filter, which can be turned inside out and still filter the coffee.

 

[miss-sanne]

I had that same question. When I think filter, I always conceptualise a coffee filter, which can be turned inside out and still filter the coffee.

Coffee filter would just make i so much easier ! I hate filtering lol

 

[Turbo-Farmer]

I tried that, lol. I don't need to filter twice, and it was also impossible.

These days, I don't filter, because no matter how I do it, I end up spilling a lot.

I guess it’s my experience being in biotech. We used these big 30” filters with a differential pressure of 30psi at the 0.2u pore size. We were filtering 30k litters at a time.

So now that I am steering my own boat it seems natural to rely on my filtration experience.

 

[lauranyc77]

I had a similar issue but the filter was not the cause. This was my first time attempting to reconstitute with filtering and venting. I watched the Peptide Test youtube video for instructions and I got both 1.5in needles and 0.5 needles

So I injected my bac water into the original vial with the tirz but when I tried to draw the reconstituted solution back into the syringe before adding the filter, the 1.5 inch needle would not draw anything. Finally gave up and switched to the .5in needle and it worked. Either I was hitting the bottom of the glass or the needle was defective. I am going to test with the old vialand syringes and water to see if those needles work. But bottom line, two different size needles is not needed and I think they push it in those videos to get you to spend more.

My other newbie issues were I could never get the .5in needle off the syringe, had to use needle nose pliers which of course is not sterile. And I think I need to buy smaller syringes. I have 10cc that I already had on hand but way too big to measure accurately