Understand the basic types and characteristics of solution formulations in pharmaceutical practice[]
Gas in Gas
liquid in liquid
solid in solid
gas in liquid
solid in gas
solid in liquid - most common
Define the various types of solutes and solvents, and their interactions with each other[]
Hydrophilic, lipophobic, "water loving" solvents dissolve ions, polar compounds, and solutes with hydrogen bonds. The solute - solvent interactions are generally strong.
Hydrophobic, lipophylic "water hating" solvents dissolve hydrocarbons and other similar moieties. The solute - solvent interactions are generally weak.
Hydrophilic/Hydrophobic solvents (like alcohols, acids, and amides) have both properties. Overall solubility depends on which characteristics dominate in the molecule.
Describe the thermodynamic process behind the formation of solutions[]
Understand the factors affecting solubility and dissolution rate[]
Understand the basics behind calculations involved in solubility and dissolution rate processes[]
Study Questions[]
What physicochemical factors affect solubility, dissolution and permeability, and how do they affect drug absorption?[]
What are the various barriers in oral drug delivery?[]
Why is the activity coefficient important for aqueous solubility?[]
Is dissolution rate important in making the decision whether a drug is formulated as immediate release or controlled release? Why?[]
Why is a formulator concerned about BCS in preference to drug MOA?[]
Which factors influence dissolution rate?[]
What are the different categories of solutes and solvents?[]
Can a reaction happen if the free energy of the process is positive?[]
Why is the salting in/out phenomenon important to the practitioner?[]
Why is buffer capacity information as important as the buffer pH?[]
What factors affect the pH of buffer solutions?[]
Can you predict the pH of an aqueous solution by knowing the chemical nature of the drug substance?[]
Study the situations under which an oral solution formulation would be advised/discouraged[]