Reduction TriggeredIn SituPolymerization in Living Mice

Abstract

“Smart” biomaterials that are responsive to physiological or biochemical stimuli have found many biomedical applications for tissue engineering, therapeutics, and molecular imaging. In this work, we describe in situ polymerization of activatable biorthogonal small molecules in response to a reducing environment change in vivo. We designed a carbohydrate linker- and cyanobenzothiazole-cysteine condensation reaction-based small molecule scaffold that can undergo rapid condensation reaction upon physiochemical changes (such as a reducing environment) to form polymers (pseudopolysaccharide). The fluorescent and photoacoustic properties of a fluorophore-tagged condensation scaffold before and after the transformation have been examined with a dual-modality optical imaging method. These results confirmed the in situ polymerization of this probe after both local and systemic administration in living mice.

Cell‐Selective siRNA Delivery Using Glycosylated Dynamic Covalent Polymers Self‐Assembled In Situ by RNA Templating

“…Rare examples of in situ polymerization in aqueous media take place at low concentration. Rao and co‐workers used rigid monomers to achieve in situ polymerization with 80 % conversion into polymers at concentration as low as 0.1 mM [8] . Template effects, a hallmark of supramolecular chemistry, can affect ring‐chain equilibria by increasing the local concentration of pre‐associated monomers.…”

Chemical Reactions Trigger Peptide Self‐Assembly in vivo for Tumor Therapy

“…This significant difference in GSH level has promoted GSH‐responsive drug delivery strategy as an appealing solution for tumor treatment [14b,22–23] . Therefore, using GSH as a reducing agent to participate in the redox‐induced peptide self‐assembly process has an excellent application prospect [24] …”

“…Bio‐orthogonal reaction refers to any chemical reaction that can be carried out in a biological environment without disrupting the native biochemical process [33] . Bio‐orthogonal reactions commonly used in organisms include Staudinger ligation, click reactions, and the inverse electron‐demand Diels‐Alder reaction (IEDDA), cyanobenzothiazole‐cysteine condensation reaction among others [24,33–34] . The use of bio‐orthogonal reaction as the triggering factor for peptide assembly is more selective and time‐sensitive, and we can control the occurrence of the reaction to a certain extent [13,31] .…”

Characterization of Triphenylamine and Ferrocenyl Donor‐π‐Donor Vinyl BODIPY Derivatives as Photoacoustic Contrast Agents†

“…Pulsing the excitation light source generates broadband fluctuating pressure waves propagating through the medium that are converted to an electronic signal using a piezoelectric ultrasound transducer, which is further reconstructed to produce a 3D image (3). Molecular photoacoustic contrast agents (MPACs) represent a rapidly growing field of research which aims to achieve an optimum PA signal‐to‐noise ratio for targeted in vivo photoacoustic imaging (PAI) with exciting developments also taking place with respect to the development of smart MPACs derived by in vivo synthesis from small molecule precursors (4,5). As the nonradiative S 1 S 0 decay of a chromophore is typically responsible for its PA emission, at least from a HOMO‐LUMO single‐photon absorption perspective, the efficiency of an MPAC is often quantified as 1‐, where is the fluorescence quantum yield.…”