Design and characterization of a novel sensor combined imaging and zinc ion sensing

A novel fluorescent sensor for Zn(II) detection and imaging is developed by incorporating 1-(2-pyridylazo)-2-naphthol (PAN) and Rhodamine B (RB) in a sol–gel film on an end face of a gradient index (GRIN) lens rod which is tightly connected with an imaging fiber. This technique has high-quality imaging capabilities for observing remote sample while measuring Zn(II). The RB and PAN employed in combination as the indicator for zinc-sensing is much cheaper than that of the other zinc-sensitive fluorescent dyes. The sol is prepared by base catalyzed hydrolysis of tetraethylorthosilicate (TEOS) with the addition of 3-glycidyloxypropyltrimethoxysilane (GLYMO) and 3-aminopropyltriethoxysilane (APTES), which is more suitable for Zn(II) detection. The sensor has the linear range of Zn(II) from 0.1 to 1 mmol/L. Simultaneously, it has the capabilities of real-time imaging with the whole system’s resolution of 18.73 line pairs/mm. This bi-functional sensor has potential applications in in situ biosensing and other remote measurements.

► A sensor combined imaging and zinc ion sensing was fabricated.
► The sensor had high-quality imaging capabilities for observing remote sample.
► The indicators RB and PAN were employed in combination as Zn(II) indicator.
► The sol prepared in this experiment was more suitable for Zn(II) detection.