Description. Ammonium sulfate precipitation is one of the most commonly used methods for protein purification from a solution. In solution, proteins form hydrogen bonds with water molecules through their exposed polar and ionic groups.When high concentrations of small, highly charged ions such as ammonium sulfate are added, these groups compete with the proteins to bind to the water molecules.This removes the water molecules from the protein and decreases its solubility, resulting in precipitation.n solution, proteins form hydrogen bonds with water molecules through their exposed polar and ionic groups. When high concentrations of small, highly charged ions such as ammonium sulfate are added, these groups compete with the proteins to bind to the water molecules.
In the UK, a PhD stands for âDoctor of Philosophyâ, sometimes referred to as a âdoctorateâ. It is the highest level of degree that a student can achieve. At some institutions, including Oxford University, a Doctor of Philosophy is known as a DPhil.
A PhD, short for Doctor of Philosophy, may help you secure a position as a college or university professor, a researcher in a government or industrial laboratory, a consultant, or an independent practitioner. As you complete your coursework and add complexity to the topic in which you're interested, you'll likely change and add depth to your initial research interest. 2  That's ok. 3  Let the research grow you understanding of the topic, and change the way you approach it.