Yonghua Sun

Determination of naproxen in human urine by high-performance liquid chromatography with direct electrogenerated chemiluminescence detection

A simple and sensitive liquid chromatographic method coupled with electrogenerated chemiluminescence (ECL) was described for the separation and quantification of naproxen in human urine. The method was based on the ECL of naproxen in basic NaNO(3) solution with a dual-electrode system. Factors affected the ECL emission were investigated. Under the optimal conditions, the ECL intensity has a linear relationship with the concentration of naproxen in the range of 4.0 x 10(-8)g mL(-1) to 2.0 x 10(-6)g mL(-1) and the detection limit was 1.6 x 10(-8)g mL(-1) (S/N=3). Application of the method to the analyses of naproxen in human urine proved feasible.

Direct electrogenerated chemiluminescence detection in high-performance liquid chromatography for determination of ofloxacin

Ofloxacin (OFLX) exhibited strong electrogenerated chemiluminescence (ECL) in NaNO(3) solution with a dual-electrode system when constant current was exerted. Based on this observation, a sensitive direct ECL method coupled with high-performance liquid chromatography (HPLC) separation was developed for determination of OFLX in human serum. Factors affected the ECL emission were investigated. Under the optimal conditions, the ECL intensity has a linear relationship with the concentration of OFLX in the range of 1.0x10(-8) to 4.0x10(-6) g mL(-1) and the detection limit was 4x10(-9) g mL(-1) (S/N=3). The proposed method was sensitive, simple and convenient to operate.

Determination of itopride hydrochloride by high-performance liquid chromatography with Ru(bpy)32+ electrogenerated chemiluminescence detection

In this work, a stable electrogenerated chemiluminescence (ECL) detector was developed. The detector was prepared by packing cation-exchanged resin particles in a glass tube, followed by inserting Pt wires (working electrode) in this tube and sealing. The leakage of Ru(bpy)(3)(2+) can be compensated by adding a small amount of Ru(bpy)(3)(2+) into solution phase. Coupled with high-performance liquid chromatography separation, the detector has been used for determination of itopride hydrochloride in human serum. Under the optimal conditions, the ECL intensity has a linear relationship with the concentration of itopride hydrochloride in the range of 1.0 x 10(-8) g mL(-1) to 1.0 x 10(-6) g mL(-1) and the detection limit was 3 x 10(-9) g mL(-1) (S/N=3). The as-prepared ECL detector displayed good sensitivity and stability.

Determination of folic acid by high‐performance liquid chromatography with direct electrogenerated chemiluminescence reaction

In our present work, it was found that the electrooxidation of folic acid (FA) was accompanied by electrogenerated chemiluminescence (ECL) emission. Out of the four inorganic salts, NaNO(3) solution was found to be a suitable supporting electrolyte for the ECL emission of FA. Coupled with high-performance liquid chromatography separation, this simple ECL method was used for post-column determination of FA. Under the optimal conditions, the ECL intensity has a linear relationship with the concentration of FA in the range of 1.0 x 10(-7) to 1.0 x 10(-5) g/mL and the detection limit was 5 x 10(-8) g/mL (signal-to-noise ratio = 3). Application of the present method to the analysis of FA in human urine proved feasible.