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.
â¢ Both PhD and EdD are research based doctoral level degree programs that require original research by the student. â¢ PhD is a degree awarded in most fields of study whereas EdD remains an education based degree. â¢ PhD is called the Doctor of Philosophy whereas EdD is called the Doctor of Education. â¢ PhD is common in English speaking countries, especially UK and the rest of the commonwealth. â¢ For students desirous of a career in teaching to become professors one day, PhD is a better option.