0000000000536125
AUTHOR
Regine Süss
Poly(sarcosine) surface modification imparts stealth-like properties to liposomes
Circulation lifetime is a crucial parameter for a successful therapy with nanoparticles. Reduction and alteration of opsonization profiles by surface modification of nanoparticles is the main strategy to achieve this objective. In clinical settings, PEGylation is the most relevant strategy to enhance blood circulation, yet it has drawbacks, including hypersensitivity reactions in some patients treated with PEGylated nanoparticles, which fuel the search for alternative strategies. In this work, lipopolysarcosine derivatives (BA-pSar, bisalkyl polysarcosine) with precise chain lengths and low polydispersity indices are synthesized, characterized, and incorporated into the bilayer of preformed…
Inside a Shell—Organometallic Catalysis Inside Encapsulin Nanoreactors
Abstract Compartmentalization of chemical reactions inside cells are a fundamental requirement for life. Encapsulins are self‐assembling protein‐based nanocompartments from the prokaryotic repertoire that present a highly attractive platform for intracellular compartmentalization of chemical reactions by design. Using single‐molecule Förster resonance energy transfer and 3D‐MINFLUX analysis, we analyze fluorescently labeled encapsulins on a single‐molecule basis. Furthermore, by equipping these capsules with a synthetic ruthenium catalyst via covalent attachment to a non‐native host protein, we are able to perform in vitro catalysis and go on to show that engineered encapsulins can be used …
Polysarcosine-Based Lipids: From Lipopolypeptoid Micelles to Stealth-Like Lipids in Langmuir Blodgett Monolayers.
Amphiphiles and, in particular, PEGylated lipids or alkyl ethers represent an important class of non-ionic surfactants and have become key ingredients for long-circulating (“stealth”) liposomes. While poly-(ethylene glycol) (PEG) can be considered the gold standard for stealth-like materials, it is known to be neither a bio-based nor biodegradable material. In contrast to PEG, polysarcosine (PSar) is based on the endogenous amino acid sarcosine (N-methylated glycine), but has also demonstrated stealth-like properties in vitro, as well as in vivo. In this respect, we report on the synthesis and characterization of polysarcosine based lipids with C14 and C18 hydrocarbon chains and their end g…