What is Colloidal biology and does it have any scientific background?
There are two antipodes: The molecular (or makromolecular) biology, which has the concept of large macromolecules which fulfill one task. This can for example be an enzyme which breaks down its subtrate. The properties and the structure of all molecules of the enzyme are the same and the factor determining the function of the enzyme.

The coloidal biology assumes that the function is granted by adding small amounts of an enzyme to water to form a colloid, which thenchanges the properties of the water in the way that it does break down the subtrate. Life was also explained as the sum of the functions of the colloids building the body. 

This theory came up in a time when macromolecules and their functions where not very well understood. The better understanding of macromolecules rendered this theory irrelevant. This is also neatly sumarized in the conclusions section of the article you cite.