Positive Controls

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Validated positive control compounds from Xenometrix for bacterial mutagenicity (Ames), SOS genotoxicity (umuC), and chromosomal damage (micronucleus) assay systems.

Positive controls are required by OECD test guidelines and ICH S2(R1) in every assay run to demonstrate that the assay system is performing with the expected sensitivity — positive control results outside the historical data range indicate assay failure and invalidate study data.

Xenometrix supplies positive controls at validated reference concentrations in appropriate solvent systems, with lot-specific data confirming performance in the designated assay system.

Direct-acting positive controls (without S9 metabolic activation): 4-nitroquinoline-1-oxide (4-NQO) for TA98 frameshift mutagenicity and umuC SOS induction; sodium azide for TA100 base-substitution reversion; methyl methanesulfonate (MMS) for alkylating agent response.

S9-dependent positive controls (with metabolic activation): 2-aminoanthracene (2-AA) for TA98 and TA100 with Aroclor-induced S9; benzo[a]pyrene for CYP1A1-mediated activation confirmation.

Micronucleus assay positive controls: mitomycin C (clastogenic, DNA crosslinker, kinetochore-negative) and colchicine (aneugenic, spindle poison, kinetochore-positive) for MoA classification per OECD TG 487.

All positive control compounds include certificates of analysis with purity and lot-specific assay performance data. For Research Use Only. Not for use in diagnostic procedures.

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