A calix[4]arene-based fluorescence turn-off probe for the detection of dopamine as well as ascorbic acid

A fluorescent emitting system for fluorescent detection of different biomolecules was developed utilising a calixarene-based chemosensor (AntUr-AzClx). Recognition studies were conducted on various biomolecules including L-alanine, (+)-sodium-L-ascorbate (SAA), L-cysteine, α-D-glucose, glycine, D-glutamic acid, urea, and dopamine (DA). AntUr-AzClx with fluorescent emission at 446 nm under an excitation wavelength of 274 nm displayed outstanding selectivity with a turn-off response only towards DA and SAA among the other biomolecules tested. The limits of detection of AntUr-AzClx for DA and SAA were calculated sequentially as 0.13 and 0.51 µmol L⁻¹, demonstrating that the probe enables to recognise in their very low levels. Furthermore, AntUr-AzClx exhibited excellent sensitivity to detect the contents of ascorbic acid in various fresh fruits. This is an efficient, rapid, highly sensitive and selective system to determinate the contents of DA in the solution and AA in both of the solution and fresh fruits using AntUr-AzClx.