Filtering doodad - 3d print

[aromatizer]

Holds a 50-60ml syringe at full extension unlike the caulking guns I tried, which tops out at about 15ml out of 60. Can't find 100ml sterile syringes except in glass which I have no confidence of being able to sterilize properly, so not tested. Found it on telegram testing group, kudos to the original sender. Holds steady and plenty strong in PLA at 50% infill. Has adapter for 20ml, which can be modified for 10ml. Uses Irwin mini 12" quick grip.

Makes filtering an absolute breeze.

3d print files

https://3dgo.app/models/thingiverse/6322392

 

[maddie]

This is awesome thanks! I just broke out my printer and I'll definitely print this.

 

[Photon]

I assume 32 is 100ml/60?
32mm, 30mm, and 25mm

What about 30 and 25?

 

[bananafeet]

Haha reminds me of this meme:

In all seriousness those little syringe filters have a pressure rating. I think you could exceed it with that contraption.

 

[Photon]

Haha reminds me of this meme:View attachment 374111

In all seriousness those little syringe filters have a pressure rating. I think you could exceed it with that contraption.

I've had syringes crack and the syringe filter remain intact..I don't even know how but....

 

[bananafeet]

I've had syringes crack and the syringe filter remain intact..I don't even know how but....

I think the membrane itself is only meant to handle a certain psi. I'm probably being pedantic....

 

[Photon]

I think the membrane itself is only meant to handle a certain psi. I'm probably being pedantic....

Yea it'll blow. Yes your right

 

[aromatizer]

I assume 32 is 100ml/60?
32mm, 30mm, and 25mm

What about 30 and 25?

yep. 30mm holds 60ml, 25mm holds 20ml. 10ml is 17mm, modified 25
dunno about 100ml

 

[aromatizer]

I think the membrane itself is only meant to handle a certain psi. I'm probably being pedantic....

you'll feel it if it blows

 

[aromatizer]

Syringe Size	Estimated Pressure from Moderate Hand Force	Risk Level
3 mL	~100 psi	High (Easily exceeds 87 psi limit)
5 mL	~75 psi	Moderate (Approaching safety limit)
10 mL	~50 psi	Low (Safe for most filters)
20 mL	~30 psi	Very Low

use a 20ml syringe for 10ml vials. GTG

 

[bananafeet]

you'll feel it if it blows

Bro I ain't smart enough to argue this shit. Been a long time since I did anything remotely academic.

I found this tho:

https://hal.science/hal-01451400v1/document

Basically some bacteria can be pushed through the filter if they aren't rigid. The higher the pressure the higher the chance of contamination.

This article covers 0.4um filters, but I'd say the same thing applied.



Common sense would say that you'd probably reach the penetration stage of the filter before catastrophic failure (syringe bursting or membrane punctured).

After the membrane is punctured the bacteria can grow through it apparently.

I've never resused a filter, so i suppose best practice is max 24 hours before discarding.

Grow-Through and Penetration of the 0.2/0.22 "Sterilizing" Membranes | Pharmaceutical Technology

The authors encourage the investigation into whether the occurrence of grow-through and the diminution in the size of certain organisms when in contact with given liquids are the same phenomenon manifested under different circumstances.

www.pharmtech.com

 

[aromatizer]

• Maximum Operating Pressure: Most lab-grade 32mm filters (PES, PTFE, or PVDF) are rated for a working pressure of 87 psi.
• Burst Pressure: The point of total failure is often rated slightly higher, around 100–102 psi, but you should never aim for this.
• Effective Filtration Area (EFA): A 32mm filter has an EFA of roughly 4.4 to 4.9 cm². This larger surface area (compared to 25mm filters) allows for faster flow, which actually reduces the need for excessive force.

Warm the oil to around 45C. Use a 20ml syringe for single 10ml vial, ptfe 0.22um 30-33mm lab quality filters. I find warmed chinese MCT oils require hardly any pressure once warmed.

50ml+ syringes would have less pressure for doing a number of vials. If the filter develops a lot resistance obviously don't force it, swap to a new filter.