by Elio — Let me me­an­der a bit be­fore tack­ling the topic of how small a size mi­crobes can at­tain. One of the main tools in this busi­ness is fil­tra­tion, a tech­nol­ogy that we tend to take for granted in the mi­cro­bi­o­log­i­cal lab. Yet, fil­tra­tion has a no­table his­tory and no­table ap­pli­ca­tions. It was used...