Whatman... .20 or .45 ?

[AnonCanada]

No its not fine to use a .45. Do you have any idea the size of bacteria? Do you how much can pass through as small as .3?

This is horrible information please stop telling people this as it could cause and abscess.

The compounding pharmacy that makes my HRT test uses a .45micron syringe filter. Used them for 10+ years with no abbesses. IMHO a .25 filter doesn't make up for the shortcomings of a truly sterile environment.

 

[goin on 4T]

The compounding pharmacy that makes my HRT test uses a .45micron syringe filter. Used them for 10+ years with no abbesses. IMHO a .25 filter doesn't make up for the shortcomings of a truly sterile environment.

You can promote your .45 all you want, simply said its not the safest route. You cant argue that fact with your compounding pharm all you want. Do they autoclave after filtering?

Why cut corners on safety or yourself or others?
Just a poor decision.

 

[AnthonyMarco]

The compounding pharmacy that makes my HRT test uses a .45micron syringe filter. Used them for 10+ years with no abbesses. IMHO a .25 filter doesn't make up for the shortcomings of a truly sterile environment.

I agree if you have some way to sterilize after filtering (autoclave/UV/etc.) .45 would be fine since the only reason to use .2 micron is to sterilize. But not many people have the means to sterilize after filtering, and not many people have a hepa laminar flow hood, so I will personally use .2 from now on just to be sure.

On a side note, I do want to experiment with pressure cooker sterilization though. I don't have any idea if it will work or the liquid will stay in the vial, but it would be nice if I can make it work.

My thought is if it can sterilize food, surely it can sterilize other things.

 

[goin on 4T]

Yes it can and does work.

 

[AnthonyMarco]

Yes it can and does work.

Awesome.

My son starts kindergarten Tuesday, and my wife starts teaching tomorrow, so I will have the house to myself all week for testing out approximate time frames for different packing densities. Surely I can plot some semblance of an exponential graph to be used as a guideline by others.

Thanks 4 T. I appreciate the replies, and am always interested in learning something new.

Anthony

 

[goin on 4T]

Cool. Sounds like you have a better background in this stuff than I do. I hear if you have the money just buy an autoclave much less analysis required. Seal the door, flip the switch, 20 minutes later sterile vials.

 

[ChemicalAmerica]

Hello my friends, I am new to this forum.
I filter all my oil stocks 0.45u before it.

We use two vacuum filtration units connected to a hand pump.
For the final product I use only 0.2u

My equipment is identical to the one below, two units of 250ml:

https://lh3.googleusercontent.com/E...v3PbnlXa_jW68iP1EhrKe979I-1F3kB_7Yke_2w=w1600

Sorry for the English translator.

 

[MaxxReps]

On a side note, I do want to experiment with pressure cooker sterilization though. I don't have any idea if it will work or the liquid will stay in the vial, but it would be nice if I can make it work.

I pressure cooked agar slants in test tubes in a pressure cooker and the agar stayed in the tubes but they were only about 1/2 full. The trick is to let it cool fully before opening it (which I couldn't do as I PC'd them upright and layed them down to solidify after taking out of the PC and sealing them).

Problem with letting it cool is it sucks in unsterile air and if you have a pressure relief needle in the vial you could end up contaminating the vial.

 

[goin on 4T]

You should pressure cook your sealed vials.

 

[MaxxReps]

You should pressure cook your sealed vials.

Have you done this? I've been thinking about this. The temp in a PC is lower than the boiling point of BB and BA and well under the smoke point of the oil, so the vials should not explode.

Would the heat affect the gear?

This would be the easiest way to make sterile preparations. I don't think you'd even need to prefilter the oil. Why doesn't everyone do this?