Quote Originally Posted by Enigma View Post
To answer your question simply, Yes! BA will kill most everything that is of concern. Autoclaving won't even kill many of the bacterial spores mentioned because they are encapsulated in a "shell" which protects them from extreme environments, e.g. heat. In fact, mycologist will soak substrates overnight in warm water to sort of give these spores a false sense of security and many will "expose" themselves, making them susceptible to subsequent autoclaving.

Rather than buy an autoclave, try placing membranes into individual autoclave bags ( I have used simple vacuum seal/boiling bags) and vacuum sealing them. Put them in a pressure cooker for 30 minutes at 15psig.
This will "sterilize" your membranes. I have had success only with PVDF using this method as nylon tends to stick or melt into the bag.

All of the is quite pointless though if you aren't filtering and packaging under laminar flow. Baking your glass and autoclaving your filters is an exercise in futility if you them expose these depyrogentated items to open air.

In the "for-self" producing, home brew environment, I think simply placing/soaking filter membranes in BA prior to use ( I suggest nylon for cost and compatibility) and baking your glass filter rig just prior to use.
In our lab we bake all glassware in a lab oven for a minimum of one hour at 197 celsius. Much of it sits in the oven for hours and is cooled under laminar flow.
For the home brewer, try placing glassware in an oven bag and baking at 375F for 30 or more minutes. You can let cool in the oven and then open just prior to use. You can take it a step further by wiping the bags down with Iso alcohol before opening them.

I used to convert Finaplex pellets in the open kitchen air and never got sick. Makes me queasy thinking about those days but I also know most healthy people are unaffected by most of these pathogens.
Thank you for the very insightful post! I have studied and studied aseptic techniques. I will be using a bunsen burner while working in situations where asceptic techniques are important; I will purchase a flow hood in the very near future as well, along with an autoclave (I will also build a "clean room" in which the air is scrubbed 6 times per hour utilizing HEPA filtration.

The autoclave-bags-in-a-pressure-cooker is a great idea (I'll probably purchase Cardinal brand bags).

I also have studied and researched types of filter/membranes (over 15 hours of research--my degree is in research) and I have found that PVDF, UNLAMINATED PTFE (umlaminated meaning not backed by a polymer that does not resist the chemicals we use in AAS even though the PTFE portion will handle the solvents/esters), and Regenerated Cellulose. I purchased some 47mm 0.2 micron Whatman PTFE, polypropylene-backed membranes (can you say $500 mistake) and the Benzyl Benzoate melted the polypropylene from the filter/membrane (the filtered oil had a "clear crust" similar to that of a crust on top of lava after spewing from a volcano). After further research, PP is not compatible. So, I'll be using regenerated cellulose after extensive research (I may also give PVDF and unlaminated PTFE membranes a try).

Again, thank you for your helpful insights!