Synthesis and Evaluation of Chromo-Fluorescent Properties of a New Class of Aza/ Substituted Acenes

Abstract

We have developed several chromo-fluorescent probes for sensing of specific ions. All the probes possessed the capability of visual eye sensing and gave fluorescence “off-on” switch for particular ion. Phenalenedicarbonitrile and their derivative have been explored less for their sensing capabilities hence, we have synthesized and explored the unique sensing behavior of two phenalene based probes with different chromophoric units attached, in mixed aqueous media. Rhodamine B derivative when attached to highly electron deficient precursor i.e. Phenalenedicarbonitrile led to unique fluorescence and colorimetric “on-off” phenomenon. Further, we have synthesized rhodamine based probes (varying in the number of rhodamine units present) and explored their sensing behavior in aqueous/ mixed aqueous mediums. The presence of more rhodamine units provided multiple interaction sites for the ion to bind which led to improvement in the limit of detection of the probes. For the practical application of the probes we explored the capability of the probes to detect ions in industrial waste water and tap water. In addition to real-time sampling we used our probe for intracellular sensing of ions by using A549 cervical cancer line cells as well as we explored the anti-bacterial activity of probe. Furthermore, we even used our probes for construction of various molecular circuits and devices such as encoders, decoder, memory devices and keypad lock.