USP Container Testing

Microtest demonstrates great capability and experience in pharmaceutical container testing based on United States Pharmacopeia (USP) procedures.

Today, plastic material is most commonly used for drug containment. To detect impurities in these plastics, Microtest performs the following USP-specified physiochemical tests for product validation:
• Heavy metals: detection limit 1 ppm
• Residue on ignition: detection limit 1 mg
• Nonvolatile residues: detection limit 1 mg
• Buffering capacity: detection limit pH 1-14
• Buffering capacity using isopropyl alcohol: detection limit pH 1-14

Samples are determined by weight versus volume. Generally 4 g per 20 mL ratios are used, with 100 mL required for a complete physiochemical analysis. Samples by surface area require 120 cm2 per 20 mL.

Each test evaluates pH plus pre- and post-testing weights, or compares color reactions per relevant USP monograph. Test extractions are performed at 70 °C for 24 hours.

Where less-common glass containers are employed instead, Microtest uses the following tests of chemical resistance for new materials product validation:
• Water attack at 121 °C
• Powdered glass water attack at 121 °C
• Arsenic test: detection limit tested against 0.1 ppm of arsenic

With glass, samples must be characterized prior to testing as Type I, II, III, or NP. A minimum of 20 vials for each glass type must be supplied.

In both plastics and glass procedures, samples are tested against a specified USP monograph standard, and all sample testing is quality-controlled under Microtest’s rigorous GMP program.