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USP HPLC Organic Impurity Analysis for Lamotrigine Tablets (SST) on an Ascentis® Express C18

USP HPLC Organic Impurity Analysis for Lamotrigine Tablets (SST) on an Ascentis® Express C18

Materials

analytical column

Product No.
Description
Pricing

Ascentis® Express C18, 5 μm HPLC Column

5 μm particle size, L × I.D. 25 cm × 4.6 mm

mobile phase component

Product No.
Description
Pricing

Lamotrigine Related Compound C

United States Pharmacopeia (USP) Reference Standard

Acetonitrile

isocratic grade for liquid chromatography LiChrosolv®

Methanol

for liquid chromatography LiChrosolv®

Ammonium acetate

for HPLC LiChropur

Water

for chromatography (LC-MS Grade) LiChrosolv®

sample prep

Product No.
Description
Pricing

Millex® PVDF syringe filter

pore size 0.45 μm, diam. 33 mm, non-sterile, hydrophilic

standard

Product No.
Description
Pricing

Lamotrigine

United States Pharmacopeia (USP) Reference Standard

Lamotrigine Related Compound B

United States Pharmacopeia (USP) Reference Standard

CONDITIONS

column

Ascentis® Express C18, 250 x 4.6 mm I.D., 5 µm (50538-U)

mobile phase

Acetonitrile:methanol:buffer (10:30:60) v/v/v; Buffer– 0.8 g/L of ammonium acetate, adjusted with glacial acetic acid to a pH of 4.5

gradient

Isocratic

flow rate

1 mL/min

pressure

216 bar (3132 psi)

column temp.

Ambient

detector

UV, 210 nm

injection

5 µL

sample/matrix

System suitability solution - 1.0 µg/mL of lamotrigine related compound B and 0.4 mg/ml of lamotrigine in methanol and buffer (60:40) v/v

Description

General description

Lamotrigine is an anti-convulsant medication used to treat epilepsy and to delay or prevent the recurrence of depressive episodes in bipolar disorder. For epilepsy, this includes focal seizures, tonic-clonic seizures, and seizures in Lennox-Gastaut syndrome.
In bipolar disorder, lamotrigine has not been shown to reliably treat acute depression, but for patients with bipolar disorder who are not currently symptomatic, it appears to be effective in reducing the risk of future episodes of depression.
This application illustrated the system suitability for the organic impurity analysis for lamotrigine tablets testing following the currently official United States Pharmacopoeia monograph

Analysis Note

For the lamotrigine standard solution, the RSD was 0.43 (USP specification NMT 10% RSD) and the tailing factor for lamotrigine was 1.7 (USP specification NMT 2). For the displayed system suitability solution the resolution between lamotrigine and the related compound B was 2.6 (USP specification NLT 2.0).

Other Notes

App_367I

Legal Information

Ascentis is a registered trademark of Merck KGaA, Darmstadt, Germany