Formation of thermo‐sensitive polyelectrolyte complex micelles from two biocompatible graft copolymers for drug delivery

Abstract

Thermo-sensitive polyelectrolyte complex (PEC) micelles assembled from two biocompatible graft copolymers chitosan-g-poly(N-isopropylacrylamide) (CS-g-PNIPAM) and carboxymethyl cellulose-g-poly(N-isopropylacrylamide) (CMC-g-PNIPAM) were prepared for delivery of 5-fluorouracil (5-FU). The PEC micelles showed a narrow size distribution with core-shell structure, in which the core formed from positively charged CS and negatively charged CMC by electrostatic interactions and the shell formed from thermo-sensitive PNIPAM. The synthesized PEC micelles have lower critical solution temperatures (LCST) in the region of 37°C, which is favorable for smart drug delivery applications. The hydrogen bondings between PEC micelles and 5-FU increased the drug loading. Changing temperature, pH or ionic strength, a sustained and controlled release was observed due to the deformation of PEC micelles. Adding glutaraldehyde, a chemical crosslinking reagent, was an efficient way to reinforce the micelles structure and decrease the initial burst release. Cytotoxicity assays showed that drug-loaded PEC micelles retained higher cell inhibition efficiency in HeLa cells.

Exploring the Application of Micellar Drug Delivery Systems in Cancer Nanomedicine

“…Based on these mechanisms, the drug release of 5-FU at 37 °C was higher than that released at 25 °C. This behavior demonstrated that the release rate of 5-FU was controlled by changing external conditions [ 176 , 177 ].…”

In Situ Drug Delivery to Breast Cancer-Associated Extracellular Matrix

“…These injectable DDSs can be designed to exploit the physical abnormalities of the stiff ECM that exist in tumors (altered structural and vasculature tumor microenvironment, uneven blood flow, high interstitial pressure, poor elasticity, heterogeneous vessel permeability, and metabolic autonomy). In addition, tumor tissue exhibits elevated temperatures that reach 40–42 °C, as compared with most healthy tissues that exhibit temperatures near 32 °C. , High rates of glycolysis and rapid proliferation are thought to contribute to these elevated tumor temperatures, and temperature induced drug activation is actively being explored.…”

Ligand coordination sphere effect of Schiff base cis‐dioxomolybdenum(VI) complexes in selective catalytic oxidation of alcohols

“…Aldehydes, ketones, and carboxylic acids are essential industry products and intermediates 1 . Among them, aldehydes, 2–5 carboxylic acids, 6–8 amides, 9,10 and other derivatives are commonly found in literature as starting materials or building blocks in several synthetic methodologies. These derivatives are commonly prepared by oxidation of the corresponding alcohols as reported in literature 11 ; in this regard, organic solvents and nongreen oxidants (CrO 3 , NaClO, KMnO 4 , etc.)…”