A drug solution can retain its measured concentration while a separate question remains about microbial contamination. A syringe-storage study examined chemical stability and explicitly separated that finding from sterility.
The investigators stored selected single-drug formulations in polypropylene syringes at room temperature. They measured concentrations initially, near day 50, and at day 100 using stability-indicating chromatography. Most tested formulations retained more than 95% of their initial concentration at day 100. The diluted hydromorphone formulation was an exception. The samples remained visually clear and colorless.
The findings apply to the tested concentrations, diluents, containers and storage conditions. Visual clarity and chemical concentration do not establish absence of microorganisms. The paper’s chemical measurements cannot alone determine a preparation’s acceptable storage period or its suitability for administration.