Let me clarify a few things for those that believe we are discussing selling blood.:
Plasma is NOT blood. The plasma is removed from your blood and the blood is put back into your veins. The donation centers that pay are actually paying you for your time and you are "donating" the plasma but it is just easier to say "sell my plasma". It is a very safe process and if any of your vitals are tha least bit off (even by a point) they will NOT let you donate that day. They do a finger prick (actually to me the worst part of the whole experience) each time you go in to donate and then they check your blood for many different things to see if you can donate that day. They check your pulse, blood pressure, weight each time as well.
I have seen people from all walks of life doing this. When I used to do this I was often there the same time as other regulars which were anything from college students, to pastors, stay at home moms, medical personnel, construction workers...you name it.
This is from the Biolife website:
So, maybe you're a little nervous about coming in for your first plasma donation.


The best way to overcome your fear is to understand what happens during the donation process.
Plasma is collected through a process called "plasmapheresis." When you come in to donate, a needle is placed in your vein and your blood is pumped into a specialized spinning device that separates the plasma from the other whole blood components, such as red and white blood cells and platelets. While the plasma is collected, the other blood components are filtered into a reservoir. Once the reservoir is full, your red and white blood cells and platelets are returned to your body.
Throughout the process, the system automatically alternates between collection and replacement until the predetermined amount of plasma, based on your weight, is obtained.
The tubing and all other collection supplies that come in contact with your blood are discarded and replaced with new, sterile materials each time a donation procedure is performed.
You can do a google for donate plasma and find even more info.