Any one have any tips on how to concentrate bacterial cells? My team is trying to work with an idea from another paper of using bacteria at a concentration of 10^10 cells per ml to apply to another application. Let's say you typically have 10^8 cells per ml in an overnight culture. Any ideas how to get up to 10^10 cells per ml? I was going to count the cells to find the "specific" concentration, and then spin it down at 5000 g for 15 min, remove some of the supernatant, resuspend it, and recount it to see what my concentration is. But it seems that may not bring me to 10^10, but only concentrate the first part. For example, 5 x 10^8 cells per ml, the 5 would decrease, instead of the exponent increasing. Anyone have any links or tips to protocols?