Air in 3ML Pen Vial

[bru213]

Hi Guys,

I'm encountering an issue that I'm pointing towards the vial but I'm not sure.
Set-up - I've tried with GLOW stack and with MOTS-C - on 4 different PENS and two types on needles(unfortunately not from your website - since I'm in Europe - nevertheless I've seen if not all the majority of the clips on the youtube channel).
After filling the vial and purging it - PEN in the fridge - air in the vials - visible air(not small bubbles) - arount 10-15 units. I purge the pen again - next day air again.
The vials/pens from China - needles from BD - vials with the black mark(allegedly steam sterilized)

Any ideals where, how and why does it get air inside the vial ?

Thanks,
Chris

P.S. - Is not that i can't live with it - i can purge them everyday - but I'm just curious.
I've also used filled pens - from EU manufacturers - RETA, Melanotan II several times - this issue never happened.
So either I'm doing something wrong - or there's something with the PEN/VIAL/NEEDLE - combo

[ResearchCat]

I have the same thing happen. I assume it’s because the vials are kept cold so the liquid volume shrinks and when I insert the needle, it draws a small amount of air into it. Probably also why sometimes the needle drips a little as it warms up.

This doesn’t happen all the time for me. Oddly of the three pens I am running right now, only one is doing this.

[bru213]

@ResearchCat said:

I have the same thing happen. I assume it’s because the vials are kept cold so the liquid volume shrinks and when I insert the needle, it draws a small amount of air into it. Probably also why sometimes the needle drips a little as it warms up.

This doesn’t happen all the time for me. Oddly of the three pens I am running right now, only one is doing this.

Hey,

Thanks for the reply. Yes also the dripping issue is relatable - i didn't mention it in my initial post. I'll try next week filling some pens with "cold" vials - to see what'
s what. I've also ordered a new batch of vials from a more allegedly more reputable manufacturer.

Thanks,