แอนไอออน และกรดอะมิโนเซนเซอร์ และลูมิเนสเซนส์โมเลกุลาร์ลอจิกเกตส์

Abstract

Novel colorimetric sensors, L1H and L2H, derived from imidazolium and anthraquinone moieties were synthesized. In the presence of F-, AcO- and H2PO4-, -NHcar-CH2-Nimi- of L1H was cleaved and both amide protons were deprotonated. L1H structure is changed to be L3H form. L2H was found to undergo deprotonation processes of the NH- moiety of the amide-anthraquinone unit. These phenomena gave a dramatic color change due to charge transfer transition. Electrochemical studies showed that L2H responsed to F- because the electrochemical reduction peaks were shifted to more negative potential. L2H is able to discriminate the three group of anion depending on the basicity of anions. Moreover, amino acids (Trp, Phe and Ala) were able to bind dianion using hydrogen bonding and electrostatic force. Interestingly, the reduced form of L3H has excellent selectivity to H2PO4-. Moreover, L3H can differentiate the enantioselectivity of Phe but it is not able to discriminate the enantiomer of Trp, namely D- and L- forms observing from the analogous peaks. Molecular logic gates in micelles were successfully demonstrated using self-assembly of fluorophores (23, 24, 25 and 26) and receptors (8b, 10b, 27, 28, 29, 30 and 31) within a detergent micelle compartment. Moreover, the results show ‘plug and play’ behaviour since a given combination of one or more receptors, fluorophore and micelle could be selected as the system for a particular use. The ‘plug and play’ was shown with various types of logic gates such as PASS 0, PASS 1, YES, NOT, OR and AND were achieved. Additionally, new pyrazolines (12b, 13b, 15b, 16b, 18b and 20b) were synthesized for use as fluorescent sensors and switches responding to protons for eventually use on bead surfaces. Some of these pyrazolines behave in homogeneous solution as reconfigurable molecular logic gates. The internal charge transfer (ICT) nature of pyrazoline excited states was confirmed by the red shift of the emission wavelength as the polarity of the solvent is increased.