losses from hold-up volume in the filter and needle are common and visible with colored peptides. smaller 4 mm filters retain far less than larger ones and pre-wetting plus flushing with bac water recovers most of the material. final concentration should be checked by measuring the total recovered volume in a syringe before calculating dose.
What this discussion establishesone participant dislikes quantified overfills while others appreciate them for offsetting losses
Still openwhether regular syringe filters can be made to absorb zero peptide or if special types are required
Nothing here is advice.
I recently began filtering my peptides and noticed losing roughly three quarters of a milliliter from the slop in the filter and needle. Does this happen normally? It seems unlikely that everyone loses that volume every time.
Yeah everything's caught in the filter so I push it through with around half to one milliliter of bac.
Yeah that suggestion clicks. Realized a basic option lurked but felt too thick to notice 😆 cheers!
Reasons like this explain our fondness for accurately dosed overages. Any wastage still leaves us with the bought quantity intact.
Earlier I brought up the filtering topic yet others insisted nothing like that occurs even though the visible color proves some of the compound stays trapped inside since that one turns blue. I run liquid through ahead of time and rinse afterward with the sterile water but there's simply no way to measure exactly how much ends up caught. That other user somehow stops it from sticking at all and I figure she must be using something other than the usual kind so I'm curious what her approach is.
That volume does seem oversized for a filter. From what I gathered, picking the tiniest one matters because quite a bit of the material stays trapped inside once finished. Roughly speaking, the four millimeter version traps around point zero seven milliliters, while the thirteen millimeter version keeps four times that amount at point two eight, and the thirty three millimeter one holds point six five. For my own batches under four milliliters I stick with the smaller size, switching to the medium one beyond that amount. I mix things down so the shots stay loose enough that small measurement slips do not matter much, aiming for half a milliliter or fifty units and staying above thirty units. I also run a little extra bacteriostatic water through first by leaving some in the syringe after mixing the dry powder, then swap to the filter and push the rest through.
I handle it identically because our motivations line up. Clever thinkers! 🥹
That checks out with me. I appreciate you pointing out that my filter was oversized.
Overfills aren't something I find appealing at all.
Oh, so it's supposed to be four millimeters? Wow, that explains why the one I had ended up oversized too.
I found nothing gets wasted if I push through bacteriostatic water matching the volume that stayed caught inside the filter.
Wow it seems you've figured out the answer finally. Let everyone hear about the breakthrough right away.
I went ahead and added plenty of liquid to pull over every bit of material possible. After that I checked the total amount by sucking it into a fresh syringe without removing the needle from the container so I could figure out the resulting strength.
Felt satisfied after the full 6ml passed the 4mm successfully without any blowout or clog this attempt.
Being new here, I saw that thread about filters but don't understand it at all. Must one filter those two items, and what does the filter involve exactly? Is it available at a pharmacy? Before, I just added bac water to the bottle and drew it into a syringe the day after. Sorry about the question.
Yeah I'm planning to purchase those. Much appreciated for the info.
My initial thought was that the reference pointed to three or four pieces.
I wonder whether the smaller four millimeter versions include any pre filter layer. With the bigger thirteen millimeter ones I chose the option that already had a pre filter built in at zero point six five plus zero point two micron yet now I suspect that selection might retain extra liquid once finished which could mean it was the wrong call what do people think.
These aren't something I made. Everything looks ready to use.
I'm not sure I follow the details here. If the full amount from the container gets pulled into the needle device, does that indicate what the end strength will be? Could you lay out a little more on this?
I came across a nice recording that explains filtering.
I fill the syringe completely with the solution, making sure the liquid in the needle part is included by drawing it into the main tube. Then I check the scale to see the total amount in milliliters, like noting 1.6 if it's between certain lines. Next I return all of it to the container, and if some remains in the connection, I draw in air from the container to force it out. When pulling the needle out, I also take some air into the syringe to create a vacuum because oxygen affects the stability of the substance. To find the strength, I take the tested amount in milligrams from the container, say 10.1, and divide that by the volume in milliliters. I rely on a calculator for the math.
It's only the membrane causing trouble. These days I soak it first using sterile liquid before mixing in the powder and wait a bit during that process. It appears to make a difference. Afterwards I push through some more. Those tiny ones can be finicky at times and end up clogging or rupturing. So now I handle them with more care.
I like that method. It might reduce how much those peptides stick to the PES surface. The blow out part worries me though. I really hope it doesn't end up scattered across the surface.
Thankfully it wasn't an issue after all. The liquid ends up going right into the small bottle or holder instead. That produces so many air pockets they turn into a layer of suds. Then I have to either pull everything back out and begin again or just proceed anyway which turns out pretty annoying.
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