Determination of succinycholine in the urine and plasma by LC/MS and stability evaluation of the reference materials

The pretreatment process for succinycholine was as follows:using Oasis○R WCX as a SPE column(The sorbent is suitable for the extraction of the quaternary ammounium salts),employing 50% methanol water solution to elute impurity,and using 1mL of 10% formic acid-80% acetonitrile water solution to elute the target compound.Because succinycholine has two positive charges,the ion at m/z =145.1 as the parent ion and the ion at m/z =115.5 for the quantitative ion were determined by LC/MS(ESI).The method was evaluated by calculating the recovery with adding different amounts of succinycholine in the urine and blood.The experimental results showed that the limits of quantitation were 0.92 ng/mL in urine and 1.89 ng/mL in blood,respectively(at a signal to noise ratio of 10),and the linear ranges in different matrixes were all between 0.02 μg/mLand 100 μg/mL.In the work,we also made the static evaluation for the reference materials by depositing 1μg/mL succinycholine in different mediums and measuring the respective responses during 10 days.The results showed that succinycholine was stable in the plastic,and it degradated obviously in the glass with degression of almost 90%.