A pH‐Triggered Polymer Degradation or Drug Delivery System by Light‐Mediated Cis/Trans Isomerization of o‐Hydroxy Cinnamates

Alex Abramov,David Díaz Díaz,Ina Keridou,Binoy Maiti,Jordi Puiggalí,Oliver Reiser

doi:10.1002/marc.202170050

Abstract

Back Cover: For article number 2100213 by David Díaz Díaz, Oliver Reiser, and co-workers, the image illustrates the molecular conversion of a cinnamate to a coumarin molecule upon irradiation with light of three different wavelength possibilities. In this case only the blue light is hitting the polymer, which is represented by the ball chain. The blue light is cleaving the polymer to the degradation products (balls). In the background is the actual molecular formula of the polymer.

Highlights

“smart” polymers, which have gained interest from industry and academia alike
Choosing 1a as a model substrate (Table 1), we established that no formation of the coumarin product 2a is observed either upon irradiation at 455 nm without the addition of base N,Ndiisopropylethylamine (DIPEA) or in the presence of a base without irradiation
Substrates 1b–1g could be transformed to the corresponding coumarins 2b–2g upon irradiation at 455 nm (Table 1), going along with a bathochromic shift upon addition at DIPEA (Figure S10, Supporting Information)

Summary

Introduction

“smart” polymers, which have gained interest from industry and academia alike. The release of drugs under visible light irradiation based on the cyclization of exposure of the material to environmenortho-hydroxy-cinnamates (oHC) to coumarins is described. The key oHC tal changes such as temperature, pH, restructural motif can be readily incorporated into the rational design of novel photocleavable polymers via click chemistry This main-chain moiety undergoes a fast photocleavage when irradiated with 455 nm light provided dox, enzyme, voltage, gas, mechanical force, and light causes alterations in the physical and chemical properties, which leads to changes in dimensions, aggregation states, that a suitable base is added. Two water-soluble PEG-based drug-carrier molecules involved, and allow the tuning of relevant parameters such as light intensity or irradiation time and wavelength. In this context, light-cleavable polymers are of special value:[3] Their ability to degrade (mPEG2000-oHC-benzhydrol/phenol) are synthesized and used for drug into smaller fragments upon irradiation delivery studies, monitoring the process by UV–vis spectroscopy in an ON/OFF intermittent manner.

Methods

Results

Conclusion