Thin Layer Chromatography Identification Test for Bupivacaine following European Pharmacopeia Monograph on Silica Gel G F 254 Plates

European Pharmacopoeia monograph method

Introduction

Bupivacaine, often marketed under the brand name Marcaine, is used for local infiltration, peripheral nerve block, sympathetic nerve block, and epidural and caudal blocks. It is on the World Health Organization's List of Essential Medicines, and it is the most commonly used local anesthetic in epidural anesthesia during labor, as well as in postoperative pain management.

Current European pharmacopoeia (version 9.5) indicates that a TLC silica gel G plate should be used for the Bupivacaine identification test B. TLC silica gel G plate complies with the requirements for a TLC silica gel plate R but with the following modification, it contains calcium sulfate hemihydrate as binder.
With this application note we elaborate how Silica Gel G are suitable to use for the Bupivacaine Hydrochloride identification test.

Bupivacaine hydrochloride
Bupivacaine Hydrochloride
1-butyl-N-(2,6-dimethylphenyl)piperidine-2-carboxamide;hydrochloride
 

Experimental Conditions
TLC Plate Silica Gel 60G F254  20 x 20 cm   Injection volume 5 µL
Detection Spray with dilute potassium iodobismuthate solution.    
Mobile Phase Concentrated Ammonia:Methanol 0.1:100 (v/v)
Plate development Prewash the plate in methanol and allow to dry in air before use. Use mobile phase described above. Spot standard and sample.
Development   Over a path of 10 cm
Diluent Methanol
Drying In air
Standard Dissolve 25 mg of Bupivacaine Hydrochloride CRS in methanol and dilute to 5 mL with the same solvent.
Sample Dissolve 25 mg of substance to be examined in methanol and dilute to 5 mL with the same solvent.

 

TLC plate after development
TLC plate after development
 

Chromatograms
Chromatograms
 

Chromatographic Data (Standard Solution)

Chromatographic Data (Standard Solution)

  Compound Rf Area
1 Bupivacaine Hydrochloride 0.71 1230

 

Chromatographic Data (Sample Solution)

Chromatographic Data (Sample Solution)

  Compound Rf Area
1 Bupivacaine Hydrochloride 0.71 1290

 

Conclusions

  1. The principal spot in the chromatogram obtained with the test solution is similar in position, colour and size to the principal spot in the chromatogram obtained with the reference solution.
  2. Silica gel G plates can be used for the Bupivacaine identification test B and they comply to all requirements as per the European Pharmacopoeia.

Materials

     
Related Links