The current status of MOF and COF applications

The amalgamation of different disciplines is at the heart of reticular chemistry and has broadened the boundaries of chemistry by opening up an infinite space of chemical composition, structure, and material properties. Reticular design has enabled the precise prediction of crystalline framework structures, tunability of chemical composition, incorporation of various functionalities onto the framework backbone, and as a consequence, fine-tuning of metal-organic framework (MOF) and covalent organic framework (COF) properties beyond that of any other material class. Leveraging the unique properties of reticular materials has resulted in significant advances from both a fundamental and an applied perspective. Here, we wish to review the milestones in MOF and COF research and give a critical view on progress in their real-world applications. Finally, we briefly discuss the major challenges in the field that need to be addressed to pave the way for industrial applications

A Polymer Physics Perspective on Why PEI Is an Effective Nonviral Gene Delivery Vector

Polyethyleneimine (PEI) was the first polycation shown to have a high transfection efficiency among nonviral gene delivery vectors. The high transfection efficiency was attributed to the proton sponge effect due to the partially protonated amines on PEI chains. Although the proton sponge effect has been debated, here we provide a look at PEI structure and dynamics from a polymer physics perspective. We discuss the protonation equilibrium on PEI chains, the conformational change of PEI chains, and the ion condensation on PEI chains. These three processes can all act favorably for the release of nucleic acids from the endosome and lead to high transfection efficiency. These three processes all stem from the unique chemical structure of PEI, exemplifying how chemical structure determines property