Novel Planar Chip Biosensors for Potentiometric Immunoassay of Acid Phosphatase Activity Based on the Use of Ion Association Complexes as Novel Electroactive Materials

作者：Kamel Ayman H^*; Galal Hoda R; Hanna Adly A

来源：International Journal of Electrochemical Science, 2014, 9(10): 5776-5787.

DOI：10.1016/s1452-3981(23)08206-8

• Acid phosphatase
• Miniaturized sensors
• 1-Naphthyl acid phosphate (1-NAP)
• Enzyme assay
• PVC membrane
• Potentiometry

The construction and general performance characteristics of two poly (vinyl chloride) matrix chemical sensors for alpha-naphthyl acid phosphate (1-NAP) substrate were described. These sensors were based on the use of ion association complexes of (1-NAP) with cetylpyridinium chloride (CP) [sensor 1] and iron (II) -4,7-bathophenanthroline [Fe(bphen)(3)](2+) [sensor 2] as novel electroactive materials dispersed in o-nitrophenyloctyl ether (o-NPOE) plasticizer for ionometric sensor controls. The sensing membrane (3 x 5 mm) is immobilized on a wafer polyimide chip (size 13.5 x 3.5 mm) to offer a planar miniaturized design. The sensors displayed good selectivity and stability and demonstrates a near-Nernstian response for 1-NAP over the concentration range 1.0x10(-2) - 1.0x10(-5) and 1.0x10(-2) - 9.0x10(-6) mol L-1 with an anionic slope of -57.3 +/- 0.9 and -56.6 +/- 1.1 mV decade(-1) and a detection limit of 9x10(-6) and 8x10(-6) mol L-1 over the pH range 2.8 - 5.5 for sensors 1 and 2, respectively. The sensors were used to follow up the decrease of a fixed concentration of 1-NAP substrate as a function of acid phosphatase enzyme activity under optimized conditions of pH and temperature. A linear relationship between the initial rate of 1-NAP substrate hydrolysis and enzyme activity hold 0.01- 4.3 IU L-1 of ACP enzyme. The sensors were used for the determination of ACP enzyme activities in biological fluids of some patients suffering from prostatic cancer. The results obtained agree fairly well with data obtained by the standard spectrophotometric methods.

• 出版日期2014-10