The beginning of the 21st century was marked by the intensive development of fiber‐optic sensors. New functional materials with excellent sensory properties are required to design such sensors. Fluorescent probes for neutral and charged molecules are constantly developing. However, only a small part of the reported probes was successfully converted into functional sensing polymers and found real‐world applications. A great challenge is to retain the sensing properties of a probe in a polymer matrix. The purpose of this review is to understand how properties of a probe are changed upon incorporation into a polymer and to reveal successful approaches. The review focuses on the use of the naphthalimide‐based probes in the construction of sensing polymers. The literature overview is presented according to the nature of the guest molecules targeted for the quantitative detection: cations, anions, and small organic molecules.
11 December 2018 in Chemistry – A European Journal
Pyrene‐based cyclophanes have been synthesized with the aim to realize a bellows‐type sensing mechanism for the ratiometric detection of nucleotide concentrations in a buffered aqueous solution. The sensing mechanism involves the encapsulation of a nucleobase between two pyrene rings, which affects the monomer‐excimer equilibrium of the receptor in the excited state. The nature of the spacer and its connection pattern to pyrene rings have been varied to achieve high selectivity for ATP. The 1,8‐substituted pyrene‐based cyclophane with the 2,2’‐diaminodiethylamine spacer demonstrates the best selectivity for ATP showing a 50‐fold increase in the monomer‐excimer emission ratio upon saturation with the nucleotide. The receptor can detect ATP within the biological concentrations range over a wide pH range. NMR and spectroscopic studies have revealed the importance of hydrogen bonding and stacking interactions for achieving a required receptor selectivity. The probe has been successfully applied for the real‐time monitoring of creatine kinase activity.
5 February 2018 in The Journal of Organic Chemistry
Receptors bearing hydrogen and halogen bond donors for recognition of perrhenate and pertechnetate were designed and studied. Acyclic hosts with N–H and C–H binding sites showed the best selectivity for TcO4− and ReO4− over spherical and more basic tetrahedral anions.