Post-functionalization of drug-loaded nanoparticles prepared by polymerization-induced self-assembly (PISA) with mitochondria targeting ligands.

Herein, the postfunctionalization of different non-fouling PISA particles, prepared from either poly(oligo ethylene glycol methyl ether methacrylate) (pPEGMA) and the anticancer drug PENAO (4-(-(-penicillaminylacetyl)amino)phenylarsenonous acid) or zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) and PENAO were reported. Both PISA particles were reacted with triphenylphosphonium (TPP) as mitochondria targeting units in order to evaluate the changes in cellular uptake or the toxicity of the conjugated arsenic drug. Attachment of TPP onto the PISA particles however was found not to enhance the mitochondrial accumulation, but it did influence overall the biological activity of pMPC-based particles in 2D and 3D cultured sarcoma SW982 cells.

Direct Comparison of Poly(ethylene glycol) and Phosphorylcholine Drug-Loaded Nanoparticles In Vitro and In Vivo.

Phosphorylcholine is known to repel the absorption of proteins onto surfaces, which can prevent the formation of a protein corona on the surface of nanoparticles. This can influence the fate of nanoparticles used for drug delivery. This material could therefore serve as an alternative to poly(ethylene glycol) (PEG).

Length of the Stabilizing Zwitterionic Poly(2-methacryloyloxyethyl phosphorycholine) Block Influences the Activity of the Conjugated Arsenic Drug in Drug-Directed Polymerization-Induced Self-Assembly Particles.

We report on the synthesis of poly(2-methacryloyloxyethyl phosphorycholine--PENAO)--poly(methyl methacrylate) core-shell nanoparticles which carry different chain lengths of zwitterionic 2-methacryloyloxyethyl phosphorycholine (MPC) on a nanoparticle surface. The particles, 30-40 nm in size, were readily obtained by polymerization-induced self-assembly (PISA) of the corresponding arsenic-based MPC polymers as the stabilizer block and methyl methacrylate (MMA) as the core-forming block. Zwitterionic nanoparticles are ideal candidates for protein-repellent materials.

Direct Polymerization of the Arsenic Drug PENAO to Obtain Nanoparticles with High Thiol-Reactivity and Anti-Cancer Efficiency.

PENAO (4-(N-(S-penicillaminylacetyl)amino) phenylarsonous acid), which is a mitochondria inhibitor that reacts with adenine nucleotide translocator (ANT), is currently being trialed in patients with solid tumors. To increase the stability of the drug, the formation of nanoparticles has been proposed. Herein, the direct synthesis of polymeric micelles based on the anticancer drug PENAO is presented.

Enhanced Antimetastatic Activity of the Ruthenium Anticancer Drug RAPTA-C Delivered in Fructose-Coated Micelles.

The ruthenium complex-dichlororuthenium (II) (p-cymene) (1,3,5-triaza-7-phosphaadamantane) (RAPTA-C)-has shown to be remarkably effective at suppressing the growth of solid tumor metastases. However, poor delivery efficacy and the lack of targeting ability of the common drug delivery system pose significant obstacles to maximize the therapeutic benefit of RAPTA-C. Inspired by the overexpression of GLUT5 transporter on the surface of breast cancer tissues but not the healthy mammary tissues, the use of d-fructose as the targeting moiety of the drug carrier can significantly improve the cellular uptake of nanoparticles, thus further enhancing the therapeutic efficiency of RAPTA-C.

Development and Applications of Transesterification Reactions Catalyzed by N-Heterocyclic Olefins.

A novel method to utilize N-heterocyclic olefins (NHOs), the alkylidene derivatives of N-heterocycic carbenes, as organocatalysts to promote transesterification reactions has been developed. Because of their strong Brønsted/Lewis basicity, NHOs can enhance the nucleophilicity of alcohols for their acylation reactions with carboxylic esters. This transformation can be employed in industrially relevant processes such as the production of biodiesel, the depolymerization of polyethylene terephthalate (PET) from plastic bottles for recycling purposes, and the ring-opening polymerization of cyclic esters to form biodegradable polymers such as polylactide (PLA) and polycaprolactone (PCL).

Nanodiamonds with Surface Grafted Polymer Chains as Vehicles for Cell Imaging and Cisplatin Delivery: Enhancement of Cell Toxicity by POEGMEMA Coating.

Nanodiamonds (NDs) are highly promising drug carriers due to their biocompatibility, manipulable surface chemistry, and nonbleaching flourescence. In this communication, we compare the cytotoxicity of three ND-cisplatin systems in which cisplatin was incorporated via direct attachment to the ND surface, physical adsorption within a poly(oligo(ethylene glycol) methyl ether methacrylate) POEGMEMA surface coating, or complexation to 1,1-di--butyl 3-(2-methacryloyloxy)ethyl)butane-1,1,3-tricarboxylate (MAETC) groups of a POEGMEMA--PMAETC surface layer. The polymer layers were introduced by grafting from RAFT-functionalized ND particles.