A luminous intensity variation fluorescent probe (Probe 1) for the detection of ferric ion was developed. The quantitative range of Fe 3+ content detected was 0-600 μM with the limit of detection at 0.76 μM. Furthermore, after 20 min of Fe 3+ addition, the intensity of the luminescence of Probe 1 solution gradually decreased with increase in Fe 3+ concentration. In addition, the B and G values of these images showed a linear relationship with Fe 3+ concentration (0-500 μM). Probe 1 was successfully used for the rapid determination of Fe 3+ concentration in real samples. This study demonstrates that Probe 1 is an excellent tool for the rapid determination of Fe 3+ content in real samples using a smart phone without professional equipment.

A solvatochromic fluorescent probe (probe 1) with D-π-A molecular configuration was developed. Probe 1 exhibited excellent polarity sensitivity. The E T (30) value of solvents demonstrated a good linear relationship with the Stokes shift of probe 1 except for DMSO. Moreover, the linear correlation coefficient value reached 0.97. The probe demonstrated different colors based on the type of solvents. With the increase in solvent polarity, the color gradually changed from blue to earthy yellow. It has a linear functional relationship between the B value (Blue, the blue primary color of light in RGB) and E T (30) values of the solvent existed. It provided strong support for the rapid determination of solvent polarity. In addition, probe 1 can be used for the determination of alcohol levels in Baijiu by smartphone.