Collaboration of cyclometalated platinum complexes and metallic nanoclusters for rapid discrimination and detection of biogenic amines through a fluorometric paper-based sensor array

Abstract

• A paper-based fluorescence sensor array is developed for biogenic amines. • Cyclometalated platinum complexes and metallic nanoclusters represent collaborative effects in detection and discrimination. • The sensor array offers rapid determination of biogenic amines in human urine. A simple and efficient fluorometric paper-based sensor array for discrimination and determination of biogenic amines (BAs) as biomarkers of graft injury has developed by combining two functional elements: (i) four cycloplatinated (II) complexes and (ii) eight metal nanoclusters with different capping agents. This combination provides a wide color emissive variation, when exposing to the BAs. The turn off interaction of the fluorescent sensor elements and BAs leads to the naked eye detectable colorimetric changes (under irradiation by UV lamp of 366 nm). Therefore, a distinct color difference map achieved for each BAs. It demonstrated that designed sensor array could discriminate BAs individually with 100% classification accuracy by principle component analysis and hierarchical cluster analysis. In addition, the proposed sensor can discriminate seven families of amines in the concentration range of 5–100 ppm. Besides, it was represented potential for quantitative assessment of hexylamine, dipropylamine, putrescine, pyridine and creatinine with limits of detections of 0.75, 0.72, 0.80, 1.7 and 1.4 ppm, respectively. The roles of each group of functional elements were investigated in qualitative and quantitative analysis. The sensor array containing four cycloplatinated (II) complexes represented higher discrimination ability whereas for quantitative analysis using all 12 elements in the sensor array gived better results. The feasibility of the real application of the fabricated sensor array was also confirmed via analyzing the five adult’s urine samples with appropriate sensitivity and accuracy.