Construction And Multi-signal Recognition Performance Of Calix[4]Arenes Assembled Interface

Nowdays, many sensors have been appeared in sample identification and environmental monitoring. By virtue of fluorometric methods can reach a much lower detection limit and the instrumentation involved is widely available, fluorescence-responsive chemosensors offer a promisingly simple and rapid approach in monitoring biological and environmental samples. In the meantime, electrochemical sensing has played a leading role by viture of real-time, particular in utilizing molecular probes to generate and transduce an analytical signal as a response to the binding event. Despite a varity of individual single-signaling sensors, which limits its scope of application, there are little multichannel signaling receptors on chemosensor. As a result, a promising way is to synthesize a molecule that is capable of reporting on the recognition through a variety of physical and chemical signal, which allows a sensor to be applied in various experimental conditions.In recent years, the identification on the interface has been paid much attention, because of its multiple methods to be characterized, such as cyclic voltammetry, impedance spectroscopy and surface-enhanced raman spectroscopy. Moreover, the wettability of the interface is important, which is obtained by measuring the contact angle and this method is simple, fast operation and visualization. Calixarene as potential sensor, has been increasely explored, because it forms a vase-like structure and the cavity is adjustable by varying the shape and size or by modifying the substituent of the upper or lower rims. According to a comprehensive analysis of the structure of the object types and other characteristics, we can design and synthesize calixarene host molecules with a certain chemical modifications through electrostatic interactions, vander waals forces, hydrophobic interactions, π-π interactions, hydrogen bonding and π-cations such force to achieve high selectivity and high sensitivity towards guest molecules. So, is it viable to design and synthesize the calixarene sensor with multisignaling? Therefore, this paper studies on the multisignaling optical-electrochemical-wettability sensors based on the functional calix[4]arene.Firstly, according to the structure of dyes,1,3-alternate naphthalene-calix[4]arene (NAC4) was designed and synthesized; then NAC4 self-assembled monolayes (SAMs) was constructed by click reaction; fluorescence, electrochemical impedance spectroscopy (EIS) and contact angle (CA) were used to characterize the interaction between NAC4 and these dyes.Secondly, ester appended calix[4]arene (EAC4) was designed and synthesized to investigate its interaction towards picrates; then EAC4 SAMs was constructed by click reaction; UV, EIS and CA were used to characterize the interaction between EAC4 and picrates; in addition, calix[4]arene without este was also used to investigate the interaction of picrates as control experimrnt; moreover, the interaction mechanism of EAC4 and Co(pic)2 was proposed by 1H NMR and MS.Thirdly, according to the structural of carbamate pesticides, naphthol-calix[4]arene (NOC4) was design and synthesized; then NOC4 SAMs was constructed by click reaction; the interaction between NOC4 and carbamate pesticides were performed by fluorescence, EIS and CA; moreover, the interaction mechanism of NOC4 and metolcarb was proposed by 1H NMR and MS.Fourth, the carboxylate pillar [5] arene (CEP5) modified Au NPs was designed and synthesized; assembled on the rough Si wafer; UV, colorimetric and surface enhanced raman spectroscopy (SERS) were used to characterize the interaction of pesticides; It was found that its detection limit of paraquat is 10-9 M by SERS.