Globular or corpuscular proteins: They have an axial ratio (length: width) of less than ten (usually 3–4) and hence possess a relatively spherical or orbit shape. These are usually soluble in water or in aqueous media, containing acids, bases, salts, or alcohol, and diffuse readily. Nearly all enzymes are globular proteins. Example: Protein hormones, blood transport…
Shake well. Keep in a cool place away from heat or sunlight. Pressurized can. Keep out of reach of children. Do not expose to temperatures exceeding 50°C. Do not spray near a naked flame or any incandescent material. Do not puncture or burn can even when it is empty.
The biological tests carried out on pharmaceutical aerosols are similar to tests performed on non-aerosol preparations. Basically they are tested for their therapeutic efficacy and toxicity. Therapeutic efficacy—the inhalation aerosols or MDIs are tested for their dose uniformity and particle size distribution along with the pharmacokinetic and pharmacodynamic studies. Topical aerosols are applied to the…
The dosing, performance and the clinical efficacy of aerosol products especially a MDI is dependent on the design of the container and valve. The efficiency and performance of the valve is determined by the following tests. Valve discharge rate gives the amount of contents dispensed in grams per second. The aerosol can is weighed and the…
The vapor pressure is determined using a pressure gauge. Excessive variations in the pressure from container to container may indicate presence of air in the head space. Can puncturing equipments are used to accurately determine the pressure. There are equipments available for both metal and glass containers. Density is determined by hydrometer or a pycnometer. The apparatus is…
Flame extension involves spraying the aerosol in an open flame for 4 seconds. The length to which the flame is extended is observed and measured. The test is to indicate the effect of an aerosol formulation on the extension of an open flame. Flash point is determined using the tag open-cup apparatus. The aerosol product is chilled to a…
Learning Objective Pharmaceutical aerosols can be evaluated by the following series of physical, chemical and biological tests:
Learning Objective The propellants meant to be used in pharmaceutical aerosols should undergo rigid quality control tests. In general, all propellants require special handling procedures and test procedures. A sample propellant is sent to the laboratory to determine its identity by gas chromatography. When a blend of propellant is present, then the composition is estimated and the vapor…