Abstract
A new, precise, and very selective method for increasing the impact and assessment of 3-nitrotyrosine (3-Nty) as a biomarker for early diagnosis of liver cirrhosis with minimal hepatic encephalopathy (MHE) disease was developed. The method depends on the formation of the ion pair associate between 3-nitrotyrosine and the optical sensor binuclear Pt-2-pyrazinecarboxylic acid (pca)-Bipyridine (bpy) complex doped in sol-gel matrix in buffer solution of pH 7.3. The binuclear Pt (pca)(bpy) has +II net charge which is very selective and sensitive for [3-Nty]−2 at pH 7.3 in serum sample of liver cirrhosis with MHE diseases. 3-nitrotyrosine (3-Nty) quenches the luminescence intensity of the nano optical sensor binuclear Pt(pca) (bpy) at 528nm after excitation at 370nm, pH 7.3. The remarkable quenching of the luminescence intensity at 528nm of nano binuclear Pt(pca) (bpy) doped in sol-gel matrix by various concentrations of the 3-Nty was successfully used as an optical sensor for the assessment of 3-Nty in different serum samples of (MHE) in patients with liver cirrhosis. The calibration plot was achieved over the concentration range 1.85×10−5 – 7.95×10−10molL−1 3-Nty with a correlation coefficient of (0.999) and a detection limit of (4.7×10−10molL−1). The method increases the sensitivity (93.75%) and specificity (96.45%) of 3-Nty as a biomarker for early diagnosis of liver cirrhosis with MHE in patients.
•Nano optical sensor binuclear Pt(pca)(bpy) was prepared and characterized.•The optical sensor is used for early diagnosis of MHE of liver cirrhosis.•The diagnosis process depends on the assessment of 3-nitrotyrosine in serum samples.•The method was validated against the standard method.