Sterility Testing
Quality control confirming the absence of viable microorganisms in injectable products. Samples are incubated in nutrient media for 14 days. Failure results in batch rejection. Sterility is an absolute requirement for all injectable peptide drugs and formulations.
Technical Context
USP <71>/Ph. Eur. 2.6.1 sterility test: membrane filtration (filter sample through 0.45μm membrane → transfer membrane to growth medium → incubate) or direct inoculation (add sample directly to growth media). Media: fluid thioglycollate medium (FTM, 30-35°C — supports anaerobic and aerobic bacteria) and soybean-casein digest medium (SCDM/TSB, 20-25°C — supports aerobic bacteria and fungi). Incubation period: 14 days minimum. Any turbidity indicates test failure → investigation required (is it true contamination or false positive?). Limitations: sterility testing is destructive (samples cannot be retested), has limited statistical power (testing a small sample from a large batch), and cannot detect very low levels of contamination. Parametric release (releasing batches based on validated sterilisation process parameters rather than sterility testing of individual batches) is accepted for terminally sterilised products but not for aseptically processed peptide products.