Stimuli-responsive Self-immolative Chemiluminescent Polymers

Molecular probes based on 3-hydroxyphenyl-1,2-dioxetane chemiluminescence light emission are widely used for various sensing and diagnostic applications (e.g., DNA, enzymatic and chemical probes). Amplification of molecular signals is an important task for the development of sensitive diagnostic probes in the field of chemical sensing. Recently, various approaches have been introduced to increase the signal-to-noise ratio of chemiluminescent light emission as a molecular signal.

This work describes the design and synthesis of a new class of self-immolative chemiluminescent polymers constructed of four complementary components: i) chemically stable 1,2-dioxatene analog incorporated an adamantyl group (bulky substituent), ii) protected 4-hydroxybenzyl alcohol substituent (self-immolative monomeric linker), iii) a chemical or biological responsive group (e.g., silyl protecting group), and iv) the monomers are linked together via carbonate linkage.

Our results show that a single cleavage event of the protecting group on the phenol results in the formation of a quinone derivative of 1,2-dioxetane, which undergoes a rapid 1,6-elimination to release the leaving group on the benzyl alcohol. A nucleophilic attack on the benzylic-methide position initiates a chemically initiated electron-exchange luminescence (CIEEL) process affording methyl benzoate and light emission.

Using this new class of chemiluminescent polymers introduce the ability to design a novel stimuli responsive chemilumnescent polymers as an amplification systems.