| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1232195 | Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy | 2015 | 8 Pages |
•LIF detector is used for tobramycin analysis in human urine.•Urine samples were injected directly without pretreatment.•Erythropoietin was analyzed in the presence of albumin by CE-UV.•EK and discontinuous buffer used to increase method sensitivity.
Complex samples analysis is a challenge in pharmaceutical and biopharmaceutical analysis. In this work, tobramycin (TOB) analysis in human urine samples and recombinant human erythropoietin (rhEPO) analysis in the presence of similar protein were selected as representative examples of such samples analysis. Assays of TOB in urine samples are difficult because of poor detectability. Therefore laser induced fluorescence detector (LIF) was combined with a separation technique, micellar electrokinetic chromatography (MEKC), to determine TOB through derivatization with fluorescein isothiocyanate (FITC). Borate was used as background electrolyte (BGE) with negative-charged mixed micelles as additive. The method was successively applied to urine samples. The LOD and LOQ for Tobramycin in urine were 90 and 200 ng/ml respectively and recovery was >98% (n = 5). All urine samples were analyzed by direct injection without sample pre-treatment. Another use of hyphenated analytical technique, capillary zone electrophoresis (CZE) connected to ultraviolet (UV) detector was also used for sensitive analysis of rhEPO at low levels (2000 IU) in the presence of large amount of human serum albumin (HSA). Analysis of rhEPO was achieved by the use of the electrokinetic injection (EI) with discontinuous buffers. Phosphate buffer was used as BGE with metal ions as additive. The proposed method can be used for the estimation of large number of quality control rhEPO samples in a short period.
Graphical abstractChemical structure of tobramycin (upper) and primary structure of human erythropoietin (lower).Figure optionsDownload full-size imageDownload as PowerPoint slide
