OldManMahoney

Does anyone know of any (widely/commercially available) plastics that exhibit 'fully'-permeable properties? That is the plastic would allow small molecules to move freely in and out (water, carbon dioxide, oxygen, nitrate etc.), but prevent viruses, bacteria etc. from entering? I believe it would need to have mesoporous/nanoporous properties. Can't find anything online! Perhaps what I'm looking for doesn't exist. Basically i'm going through preliminary research for my MSc thesis that i'll be undertaking in summer. I'm looking for a material that could contain a marine microalgae culture whilst allowing water, carbon dioxide, oxygen,nutrients and waste in and out of the container. The container would be positioned in the marine environment (under lab conditions in reality) so it would need to keep out viruses, bacteria and other competing algae. Any help much appreciated! Also i'm not sure where this post belongs.

I currently have a question sheet of biochemical statistics that I'm trying to work through. I would very much love any hints or examples of what to do for this question. I really don't know what to do, or where to begin! The reduction of a ferredoxin with ditionite (under anaerobic conditions), gave the spectra 'a' to 'h' as shown in the figure below: http://yfrog.com/0yimg28880j Spectrum 'a' represents a fully oxidised state and 'h' shows a fully reduced state. Spectra b-g represent partially and increasingly reduced ferredoxin. The volume was constant throughout the experiment and the changes in absorbance at 460 nm were linear with regard to the state of reduction of the ferredoxin. The potentials relative to a calomel electrode (+244 mV) when each spectrum was recorded is: Spectrum A B C D E F G H Potential (mv) -530 -588 -619 -635 -640 -670 -705 -740 Determine the midpoint of the protein and whether it transfers one or two electrons.