The derivatives of 2,6-dihydroxyacetophenone[4]arene were synthesized via one-step in the presence of base catalyzed cyclocondensation reaction of equimolar volumes of different aliphatic aldehydes and 2,6-dihydroxyacetophenone. All the compounds were purified by column chromatography and characterized by ¹H-NMR Spectroscopy, ¹³C-NMR Spectroscopy, IR Spectroscopy, and Mass spectrometry techniques. The compounds were provided with good yield and can be successfully useful for various amino acid detection because of the four ketone groups in 2,6-Dihydroxyaceto-phenone[4]arene were able to react with the amino group of amino acid to give a stable product formation. It was caused by the intermolecular hydrogen bonded between the two groups, ketone and carboxylic group of amino acid. This recognition of amino acid was carried out in UV-vis spectroscopic technique.

In this study, for the first time we report a highly selective and sensitive lutetium ions chemical optical sensor based on immobilization of a asymmetrically S–N Schiff’s base, namely N-(thien-2-ylmethylene)pyridine-2,6-diamine (TPD) on a triacetylcellulose membrane. This optode exhibits a linear range of 5.0 ×10-7 –1.0 ×10-5 M of the Lu(III) ion concentration with a detection limit of 9.3 ×10-8 M at a wavelength of 336 nm. The influence of responsible factors for improving sensitivity of the sensor was studied and identified. Response time of the newly designed optode was within 20-30 s depending on the Lu(III) ion concentration. Response of the optical sensor is independent of the pH of the solution in the range of 3.0–9.0. It manifests advantages of fast response time, low detection limit and most significantly, very good selectivity with respect to a number of lanthanide ions. The sensor can readily be regenerated with thiourea solutions and its response was reversible and reproducible. This optode was applied to the determination of Lu(III) in aqueous and CRM samples.