DDS-Drug Analysis II

Three equations for most math related drug analysis problems

1. C1V1=C2V2

2. Molecular weight in ng/mL=1 mM

3. Molecular weight x molarity=mg/mL

Define stock solution

Master solution usually prepared from a bulk drug from which other solutions are made

Define spiking solution

Diluted solutions prepared from the stock solution used to spike into calibration standards

Define stability indicating assay

Analytical procedure that accurately and precisely measures the active drug substance in a matrix. Must be able to do so in the presence of impurities, excipients, and degradation products.

Define forced degradation study

Stability study by which the drug product is subjected to various external stressors that assist in identifying potential reactions and degradation products

Define accelerated stability study

Stability study that increases rate of chemical or physical degradation by using exaggerated storage conditions in a short time that can be extrapolated to longer periods of time

Examples of stress conditions

1. Acid/base hydrolysis

2. Oxidation

3. Water hydrolysis

4. Thermal degradation

5. Photolytic (light exposure)