CEI-MS-07 — procedure

§4Procedure

The procedure below is written in the second person, which is the only place in the Institute's document set where that register is used. A procedure is an instruction and is written as one.

1. Verify the counter with particle standards at two sizes and record recovery.
2. Determine the blank count on the diluent; it must be below 10 % of the acceptance limit.
3. Reconstitute the sample under laminar airflow using particle-free diluent. Do not shake — agitation of a peptide solution generates aggregates and the measurement will then reflect the handling rather than the product.
4. Allow the solution to stand for 2 minutes to permit air bubbles to clear; entrained air is counted as particulate by light obscuration.
5. Count in not fewer than four aliquots, discarding the first.
6. Report counts at ≥ 10 µm and ≥ 25 µm per container.
7. Where counts approach the limit, repeat by the microscopic method, which distinguishes air from particulate and permits morphological classification.

References cited on this page

References are numbered in order of first citation in this document. Each superscript in the text links to its entry below.

1. United States Pharmacopeial Convention. General Chapter ⟨788⟩ Particulate Matter in Injections. United States Pharmacopeia — National Formulary (USP–NF) 2024;USP 2024 Issue 1. identifier not held by the Institute

Identifiers are reproduced only where the Institute holds them. Where a digital object identifier or PubMed identifier is not shown, the Institute has recorded the journal and year and has not constructed an identifier.