Pharmacy practice lab concepts

Absorption

is the process in which the molecules cross the membrane interface to enter into the interior of a cell.

Adsorption

is a term used to describe the process by which molecules of a substance (known as the adsorbate) attach to the surface of a solid substance (known as the adsorbent).

Physical adsorption(Physisorption)

is a physical process where the adsorbate is held to the surface of the solid by weak, van der Waals forces

Chemical adsorption (Chemisorption)

is a chemical process where a chemical bond (ionic, covalent) is formed between the adsorbate and the adsorbent

Activated charcoal is a

common adsorbent used in pharmacy and medicine.  It can adsorb a wide range of adsorbates (drugs and chemicals).  It is used to treat toxicity due to oral drug ingestion.

The extent of adsorption depends on several factors.

1. The properties of the adsorbate and adsorbent (affinity).

2. The surface area of adsorbent and active sites present on adsorbate (capacity).

3. The equilibrium conditions (temperature and concentration of adsorbate)

At low pressure

the extent of adsorption (x/m) varies linearly with the gas pressure

At moderate pressure,

(x/m) varies exponentially to gas pressure

At high pressure, (x/m)

is independent of gas pressure

Regression Analysis:

Before performing the statistical analysis for goodness-of-fit, the experimental data should be evaluated for errors (calculations, techniques).