Abstract:
Metformin is an anti-diabetic drug which belongs to biguanide class. It is the most
prescribed oral anti-hyperglycemic agent used in managing the type II diabetes
mellitus. It works by decreasing glucose production by the liver and increasing the
insulin sensitivity of body tissues. Since metformin is a high polar compound, the
extraction of metformin from human blood is somewhat complicated. Thus, a quick
and high-through liquid chromatography mass spectrometry (LC/MS/MS) method
has been developed and validated for the estimation of metformin in human blood
with a simple sample extraction technique. Solid-phase extraction was used for
sample preparation. Hereafter, it was followed by liquid chromatography tandem
mass spectrometric analysis and an electrospray-ionization interface. The
compound was analyzed using a shim-pack XR-ODS III (1.6 μm, 2.0 mm I.D. x 50
mm) column with the mobile phase consisting of 10 mmol/L ammonium formate in
0.1% formic acid in methanol as solvent A and acetonitrile as solvent B with
gradient elution mode at a flow rate of 0.3 mL/min for 10 min. A retention time of
0.387 min was observed for metformin. The method was validated as per the
guidelines of Scientific Working Group for Forensic Toxicology (SWGTOX) for
linearity, precision, accuracy, limit of quantification, limit of detection and recovery.
All the results obtained were found to be within the acceptance limit. Hence, the
developed LC/MS/MS method was successfully applied for the determination of
metformin in human blood. Further, it was successfully employed to measure
qualitatively metformin level in a sample obtained from a deceased person who had
committed suicide by overconsumption of metformin.
