A novel micro-extraction strategy for extraction of bisphosphonates from biological fluids using zirconia nanoparticles coupled with spectrofluorimetry and high performance liquid chromatography

Extraction of bisphosphonates from biological fluids is important and time consuming step in sample preparation procedure. This paper describes a simple and green sample preparation technique for dispersive micro solid phase extraction (DMSPE) of alendronate sodium (ALS) fromurine and serum samples prior to direct spectrofluorimetry (DSFL) and high performance liquid chromatography with fluorescence detection (HPLC-FLD), respectively. The DMSPE strategy is based on the selective chemisorption of ALS on zirconia nanoparticles (ZNPs) as an adsorbent followed by derivatization of the eluted analyte using o-phthalaldehyde (OPA) in the presence of 2-mercaptoethanol (2ME) at basic medium to form fluorescent species. The chemical and instrumental influencing parameters on DMSPE and measuring methods were optimized for the efficient extraction and determination of ALS. The presented methods were capable of extracting ALS from human urine and serum samples and determining over the wide ranges of 5–1000 and 5–2500 μg L(−1) with limits of detection (LOD) of 1.5 and 1.4 μg L(−1) for DSFL and HPLC methods, respectively. The relative recoveries for the three spiked standard levels of ALS in urine and serum samples ranged from 89.0% to 107.0%, and the intra-day relative standard deviations (%RSDs) were in the range of 2.9–7.9%.