Filtering finished oils

[Sampei]

I use a 22gauge and filter around 60c to help. I did the same as everyone else, filtered by hand one time. Now the caulking gun is the only way.

Caulking gun is awesome but I find it cumbersome if you don't have big quantity to filter.

Yesterday I was filtering with 10ml syringes and it was going super fast. Only problem is if you let the oil cool down in thsr case if become a fucking struggle.

I keep the oil at 50/60c and it filters like it's almost water.

 

[LGOP528]

Caulking gun is awesome but I find it cumbersome if you don't have big quantity to filter.

Yesterday I was filtering with 10ml syringes and it was going super fast. Only problem is if you let the oil cool down in thsr case if become a fucking struggle.

I keep the oil at 50/60c and it filters like it's almost water.

I use a 50ml and try to get the first few vials before it cools off too much. I also use MCT oil and 20% BB because it doesn’t give me issues. I would probably have to change my process with a different formula.

I did just brew a large batch of test e the other day but left most unfiltered so I could just filter it as needed. I’ll try the 10ml syringe next time.

 

[Sampei]

I use a 50ml and try to get the first few vials before it cools off too much. I also use MCT oil and 20% BB because it doesn’t give me issues. I would probably have to change my process with a different formula.

I did just brew a large batch of test e the other day but left most unfiltered so I could just filter it as needed. I’ll try the 10ml syringe next time.

I used the 50ml with caulking and you don't need warm oil with that method but again I find it easier and less cumbersome to just use 10ml syringe and keep the oil warm.

I usually brew 40ml max sometimes even 30/20ml.

If I were brewing more, caulking gun all the way.

10ml + 21g and warm oil it flow like the caulking gun and I don't have to break my fingers pushing, it just goes super smooth

If the oil get cold for any reason, just use a 5ml syringe but I keep the beaker on the magnetic stirrer heating plate turned on so it never gets cold. Unless I'm brewing in sequence in that case I gotta move fast because while I filter I have another beaker on the stirrer for the next batch xD

All MCT 25BB mostly because I brew high concentration gear

 

[LGOP528]

I used the 50ml with caulking and you don't need warm oil with that method but again I find it easier and less cumbersome to just use 10ml syringe and keep the oil warm.

I usually brew 40ml max sometimes even 30/20ml.

If I were brewing more, caulking gun all the way.

10ml + 21g and warm oil it flow like the caulking gun and I don't have to break my fingers pushing, it just goes super smooth

If the oil get cold for any reason, just use a 5ml syringe but I keep the beaker on the magnetic stirrer heating plate turned on so it never gets cold. Unless I'm brewing in sequence in that case I gotta move fast because while I filter I have another beaker on the stirrer for the next batch xD

All MCT 25BB mostly because I brew high concentration gear

Same here! Usually do 30-50 at a time. Only reason I did this big batch was because I was reading that the test E raws going bad was potentially the cause of the pip. So I figured let’s get all this in oil and use it first, given the current situation.

Caulking gun does get old with 50ml. I’ll try 10ml next time for sure. Might try the 25%BB too. I got test C to hold no issues with 20% but it’s a little thicker. Also my 350 test D is thick, I’ll try it there too.

 

[Sampei]

Same here! Usually do 30-50 at a time. Only reason I did this big batch was because I was reading that the test E raws going bad was potentially the cause of the pip. So I figured let’s get all this in oil and use it first, given the current situation.

Caulking gun does get old with 50ml. I’ll try 10ml next time for sure. Might try the 25%BB too. I got test C to hold no issues with 20% but it’s a little thicker. Also my 350 test D is thick, I’ll try it there too.

Test D 500mg 25BB works like a charm

I do test C 300mg 25BB too

 

[UberLOL]

Ive never seen the first one before..its a .22um filter that allows u to attach to an insulin syringe when drawing... But..have u seen how it works? How are you going to even attach that to the vial? You need to pour the oil into a cup then use this filter to draw from it...

Yes, upon reflection, I realise it was a foolish question.

 

[readalot]

All of that was to say that the velocity matters. lol
You could go to a larger needle and increase the velocity and still have the same problem. You could keep the smaller needle and decrease the velocity and maybe have better success but I would imagine the larger needle with higher velocity is preferred for manufacturing reasons.

Nice summary. For given Q (volumetric flowrate), velocity magnitude will be higher in the smaller diameter needle (larger gauge). Hence, to minimize wall shear stress you would go with larger diameter needle and try to reduce Q during filtration. I also posted some references that indicated shear stress on its own (without interfacial effects of air/liquid) was not enough to induce aggregation in a study.

Good to see you are studying fluid dynamics. Nice job.

R

Post in thread 'Filtering finished oils'

Feb 8, 2025

So after spending 6 hours reading the most esoteric papers imaginable about peptide manufacturing, lol, I got my answer, because the manufacturers wanted the answer, as to whether filtering (or other steps) in peptide production, damaged peptides.

TLDR: Lots of things damage peptides, and by "damage" we mean deforming them from their shape so badly they don't "snap back", so they no longer work properly, cause them to oxidize, or literally rip them to pieces.

While they found lots of damaged peptides after the .22um filtration manufacturing step, it wasn't the filter doing the...

• readalot

• 

 

[Ghoul]

Nice summary. For given Q (volumetric flowrate), velocity magnitude will be higher in the smaller diameter needle (larger gauge). Hence, to minimize wall shear stress you would go with larger diameter needle and try to reduce Q during filtration. I also posted some references that indicated shear stress on its own (without interfacial effects of air/liquid) was not enough to induce aggregation in a study.

Good to see you are studying fluid dynamics. Nice job.

R

Post in thread 'Filtering finished oils'

Feb 8, 2025

So after spending 6 hours reading the most esoteric papers imaginable about peptide manufacturing, lol, I got my answer, because the manufacturers wanted the answer, as to whether filtering (or other steps) in peptide production, damaged peptides.

TLDR: Lots of things damage peptides, and by "damage" we mean deforming them from their shape so badly they don't "snap back", so they no longer work properly, cause them to oxidize, or literally rip them to pieces.

While they found lots of damaged peptides after the .22um filtration manufacturing step, it wasn't the filter doing the...

• readalot

• 

Inner diameter of (my) Pall syringe filter male luer slip outlet is 1.3mm. The 20g needle inner diameter .7mm. 16g needle 1.39.

I think most syringe filters have the same (or smaller) inner diameter, so a 16g or larger needle is needed to not taper flow into a smaller space and increase pressure.

 

[readalot]

Inner diameter of (my) Pall syringe filter male luer slip outlet is 1.3mm. The 20g needle inner diameter .7mm. 16g needle 1.39.

I think most syringe filters have the same (or smaller) inner diameter, so a 16g or larger needle is needed to not taper flow into a smaller space and increase pressure.

https://www.hamiltoncompany.com/laboratory-products/needles-knowledge/needle-gauge-chart

Great discussion. Thanks guys.

 

[LGOP528]

Nice summary. For given Q (volumetric flowrate), velocity magnitude will be higher in the smaller diameter needle (larger gauge). Hence, to minimize wall shear stress you would go with larger diameter needle and try to reduce Q during filtration. I also posted some references that indicated shear stress on its own (without interfacial effects of air/liquid) was not enough to induce aggregation in a study.

Good to see you are studying fluid dynamics. Nice job.

R

Post in thread 'Filtering finished oils'

Feb 8, 2025

So after spending 6 hours reading the most esoteric papers imaginable about peptide manufacturing, lol, I got my answer, because the manufacturers wanted the answer, as to whether filtering (or other steps) in peptide production, damaged peptides.

TLDR: Lots of things damage peptides, and by "damage" we mean deforming them from their shape so badly they don't "snap back", so they no longer work properly, cause them to oxidize, or literally rip them to pieces.

While they found lots of damaged peptides after the .22um filtration manufacturing step, it wasn't the filter doing the...

• readalot

• 

Shit, I misread your statement but realized it after I wrote all of this. I’ll be damned if I’m going to erase it.

So you are referring to the continuity equation. Which is basically the idea of the conservation of mass in this situation. Q is not reduced by going to a larger diameter needle. The velocity is reduced.

Because we are in a closed system and dealing with an incompressible fluid. The mass in has to equal the mass out, once the system has reached steady state.

Q is the volumetric flow rate. The assumption made is that the thermal losses are not enough to change the density of the fluid. If this assumption is not correct, this problem just got a lot more complicated. I do love me some heat transfer though. The p looking letter in the above picture is the Greek letter Rho and in fluid dynamics is used for density. Since the density is not changing it cancels out on both sides. That leaves A1V1=A2V2
From the continuity equation, Q=AV(I can expand on this if requested). So it can be written as Q1=Q2. The only way for that equation to be true is if the flow rate stays the same.

As stated originally, I can not speak to the effects of the turbulence on aggregation. I know nothing about this. I only wanted to provide information on the sources of shear stress in flow through a pipe. I will go back and look at your reference.

I do enjoy this topic and don’t mind expanding further if anyone wants to know more.

 

[readalot]

Shit, I misread your statement but realized it after I wrote all of this. I’ll be damned if I’m going to erase it

So if I understand correctly, read the remaining paragraphs as if I wrote Q would be reduced?

Ok. Appreciate your effort on the post. I'll read the rest.

My point on Q is you can control that based on the force your exert on the plunger. We are in agreement. The equation shared above was to show the interrelationships among all the variables in laminar flow case.

 

[LGOP528]

So if I understand correctly, read the remaining paragraphs as if I wrote Q would be reduced?

Ok. Appreciate your effort on the post. I'll read the rest.

That was how I read it, what follows is the proof. I actually didn’t have to edit anything because I was not trying to talk shit.

 

[readalot]

That was how I read it, what follows is the proof. I actually didn’t have to edit anything because I was not trying to talk shit.

I'm neither trying to talk shit or escalate. We agree on the continuity equation and your analysis.

My point was below.

Minimize shear stress. Big needle diameter.

 

[readalot]

That was how I read it, what follows is the proof. I actually didn’t have to edit anything because I was not trying to talk shit.

And i can see where the following was confusing. My point was use a larger D needle AND push less hard. Thanks for typing up your thoughts. Well done. Good thing we aren't discussing boundary layer theory here at MESO. Appreciate the time you put into that.

Hence, to minimize wall shear stress you would go with larger diameter needle and try to reduce Q during filtration

 

[Ghoul]

Shit, I misread your statement but realized it after I wrote all of this. I’ll be damned if I’m going to erase it.

So you are referring to the continuity equation. Which is basically the idea of the conservation of mass in this situation. Q is not reduced by going to a larger diameter needle. The velocity is reduced.

Because we are in a closed system and dealing with an incompressible fluid. The mass in has to equal the mass out, once the system has reached steady state.
View attachment 316642
Q is the volumetric flow rate. The assumption made is that the thermal losses are not enough to change the density of the fluid. If this assumption is not correct, this problem just got a lot more complicated. I do love me some heat transfer though. The p looking letter in the above picture is the Greek letter Rho and in fluid dynamics is used for density. Since the density is not changing it cancels out on both sides. That leaves A1V1=A2V2
From the continuity equation, Q=AV(I can expand on this if requested). So it can be written as Q1=Q2. The only way for that equation to be true is if the flow rate stays the same.

As stated originally, I can not speak to the effects of the turbulence on aggregation. I know nothing about this. I only wanted to provide information on the sources of shear stress in flow through a pipe. I will go back and look at your reference.

I do enjoy this topic and don’t mind expanding further if anyone wants to know more.

Let me add a complication in layman's terms.

If I'm pushing 2" peaches in water through a completely filled 36" pipe, and those peaches are damaged when scraping against the pipe's surface, "interface damage", and send that flow into a 4" pipe, all other factors being equal, a much higher proportion of the peaches are likely to come into contact pipe's surface, leading to to more damaged peaches than if it were 36" all the way to the outlet, correct?

 

[readalot]

I do love me some heat transfer though

Awesome. Maybe we can do some bonding over Carslaw and Jaeger lol. Many young folks today aren't being taught all the wonderful analytical solutions available since everything done numerically now. Bummer.

 

[LGOP528]

I'm neither trying to talk shit or escalate. We agree on the continuity equation and your analysis.

My point was below.

And i can see where the following was confusing. My point was use a larger D needle AND push less hard. Thanks for typing up your thoughts. Well done. Good thing we aren't discussing boundary layer theory here at MESO. Appreciate the time you put into that.

Yes, I caught the and right before I pressed post.

Googling the equation it looks to be related to pressure drop. Can you post where you found it?

It looks to me like a calculation for the force required to achieve that flow rate.

I would think making sure there is laminar flow through the whole system would be the goal. Turbulent flow is chaotic and full of shear stress.

Boundary layer can get really deep. It is an area that I think understanding the theory and what is involved is important. For example, let’s assume the issue is from the boundary layer, I wouldn’t try to calculate it. I would make changes to the system to improve it. The test would be does the aggregation decrease.

 

[Ghoul]

And i can see where the following was confusing. My point was use a larger D needle AND push less hard. Thanks for typing up your thoughts. Well done. Good thing we aren't discussing boundary layer theory here at MESO. Appreciate the time you put into that.

We need some consideration of human nature here.

If the larger needle isn't adding any additional perceived resistance vs no needle, because its diameter is larger than the outlet of the filter, I'm not going to push harder if that needle is 1mm, 2mm or 3mm wider in diameter than the outlet, yet the velocity will decrease as flow from the filter outlet tapers up into the larger space. Unlike the significant easing of effort going from 25g to 20g, emptying the syringe much faster, I can't feel a change in effort required or time any differences in emptying the syringe with or without the 16g needle attached to the filter.

It's the narrow throat on the filter outlet that's causing the resistance I feel, regulating how hard I push, not the wider diameter needle attached to it, so pressure applied will be constant.

 

[LGOP528]

Let me add a complication in layman's terms.

If I'm pushing 2" peaches in water through a completely filled 36" pipe, and those peaches are damaged when scraping against the pipe's surface, "interface damage", and send that flow into a 4" pipe, all other factors being equal, a much higher proportion of the peaches are likely to come into contact pipe's surface, leading to to more damaged peaches than if it were 36" all the way to the outlet, correct?

Is it solely the contact with the metal that is the problem or other proteins? If it is solely the metal, I would think the boundary layer is the issue, if it is other proteins, I would think turbulence would be the main concern.

 

[readalot]

Googling the equation it looks to be related to pressure drop. Can you post where you found it?

It's just a rearrangement of Hagen-Poseuille flow (fully developed, laminar flow, Newtonian viscosity, etc) pressure drop equation giving injection force.

https://www.sciencedirect.com/science/article/abs/pii/S0378517318308305

Nice paper.