Novel Spectrofluorimetric Method for Measuring the Activity of the Enzyme α-l-Fucosidase Using the Nano Composite Optical Sensor Samarium(III)−Doxycycline Complex Doped in Sol−Gel Matrix

• Published in: Analytical chemistry (Washington) Vol. 82; no. 14; pp. 6230 - 6236
• Main Authors: Attia, M. S, Othman, A. M, Aboaly, M. M, Abdel-Mottaleb, M. S. A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.07.2010
• Subjects: Adult; Aged; alpha-L-Fucosidase - metabolism; Analytical chemistry; Chemistry; Doxycycline - chemistry; Enzyme Assays - methods; Exact sciences and technology; Female; Fluorescent Dyes - chemistry; Gels - chemistry; General, instrumentation; Humans; Male; Middle Aged; Nanocomposites - chemistry; Nitrophenols - chemistry; Samarium - chemistry; Spectrometric and optical methods; Spectrometry, Fluorescence - methods; Correlation coefficient; Human; Samarium III; Nitrophenol; Sample; Use; Color; Luminescence; Optical sensor; Artefact; Standard; Concentration; Calibration; Method; Chemical sensor; Fluorescence spectrometry; Enzymatic activity; Sol gel process; Detection limit; Doxycycline; Luminescence quenching; Reagents; Luminescence spectrometry; Serum
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac101033j

A novel, simple, sensitive, and precise spectrofluorimetric method was developed for measuring the activity of the enzyme α-l-fucosidase (AFU). The method was based upon measuring the quenching of the luminescence intensity of the produced yellow colored complex ion associate of 2-chloro-4-nitrophenol [2-CNP] and a nano composite optical sensor samarium(III)−doxycycline [Sm3+−DC]+ complex in a sol−gel matrix at 645 nm. The remarkable quenching of the luminescence intensity of the [Sm3+−DC]+ complex doped in a sol−gel matrix by various concentrations of the reagent [2-CNP] was successfully used as an optical sensor for the assessment of AFU activity. The calibration plot was achieved over the concentration range 3.4 × 10−9−1.0 × 10−6 mol L−1 [2-CNP] with a correlation coefficient of 0.99 and a detection limit of 6.0 × 10−10 mol L−1. The method was used satisfactorily for the assessment of the AFU activity in a number of serum samples collected from various patients. A significant correlation between the luminescence activity of the enzyme AFU measured by the proposed procedure and the standard method was applied to patients and controls. The method proceeds without practical artifacts compared to the standard method.