Category: Impurity Guides

October 4, 2026 · 4 min read

How Impurity Standards Are Used in HPLC and LC-MS: RRT, RRF and Method Validation

A practical guide for analysts: how impurity reference standards are used in HPLC and LC-MS: peak identification, RRT, relative response factor (RRF), forced degradation and method validation (specificity,…

Read article October 4, 2026 · 4 min read

Nitrosamine Impurities (NDMA, NDEA): Limits, Testing and Reference Standards

Everything a pharma QC lab needs to know about nitrosamine impurities: what NDMA and NDEA are, how they form, acceptable intake limits, NDSRIs, LC-MS/MS testing and the reference…

Read article October 4, 2026 · 3 min read

What Should a Certificate of Analysis (CoA) for an Impurity Standard Contain?

Section-by-section guide to an impurity reference standard CoA: identity (NMR, MS, IR), purity (HPLC/GC), water, residual solvents, potency by mass balance or qNMR, storage and retest date.

Read article October 4, 2026 · 4 min read

How to Choose the Right Impurity Reference Standard: A Buyer's Checklist

A practical checklist for QC labs and procurement teams in India: how to choose an impurity reference standard: identity, purity, CoA, salt form, quantity, stability, supplier and delivery.

Read article October 4, 2026 · 4 min read

What Are Pharmaceutical Impurities? Types, Sources and Why They Matter

A clear guide to pharmaceutical impurities: what they are, the main types (organic, inorganic, residual solvents), where they come from, ICH Q3A thresholds, and how impurity standards help…

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