Synthesis and Characterization of New Biodegradable Injectable Thermosensitive Smart Hydrogels for 5-Fluorouracil Delivery

Abstract

In this paper, injectable, thermosensitive smart hydrogel local drug delivery systems (LDDSs) releasing the model antitumour drug 5-fluorouracil (5-FU) were developed. The systems were based on biodegradable triblock copolymers synthesized via ring opening polymerization (ROP) of ε-caprolactone (CL) in the presence of poly(ethylene glycol) (PEG) and zirconium(IV) acetylacetonate (Zr(acac)4), as co-initiator and catalyst, respectively. The structure, molecular weight (Mn) and molecular weight distribution (Đ) of the synthesized materials was studied in detail using nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) techniques; the optimal synthesis conditions were determined. The structure corresponded well to the theoretical assumptions. The produced hydrogels demonstrated a sharp sol–gel transition at temperature close to physiological value, forming a stable gel with good mechanical properties at 37 °C. The kinetics and mechanism of in vitro 5-FU release were characterized by zero order, first order, Higuchi and Korsmeyer–Peppas mathematical models. The obtained results indicate good release control; the kinetics were generally defined as first order according to the predominant diffusion mechanism; and the total drug release time was approximately 12 h. The copolymers were considered to be biodegradable and non-toxic; the resulting hydrogels appear to be promising as short-term LDDSs, potentially useful in antitumor therapy.

Dual (pH- and ROS-) Responsive Antibacterial MXene-Based Nanocarrier for Drug Delivery

“…These results indicate that Fickian diffusion plays a major role in the release process. It should be noted that smaller R² values were obtained with the Higuchi models [ 53 , 54 ], confirming that they are unsuitable release mechanisms for the studied MXene-Se-DOX nanocarriers ( Table S1 ).…”

Process Optimization for Acid Hydrolysis and Characterization of Bioethanol from Leftover Injera Waste by Using Response Surface Methodology: Central Composite Design

“…The X -axis was wavenumber and Y -axis was the percent of transmittance. According to [ 42 ], the O-H stretch of hydrogen bond was ranged from 3500 to 3200 cm −1 , the C-O stretch 1260 to 1050 cm −1 , the C-H stretch from 3100 to 3000 cm −1 , and the C-C bond stretched around 1100 cm −1 . From Figure 5 , the functional group of ethanol was analyzed by using FTIR data.…”

A Comprehensive Investigation of the Structural, Thermal, and Biological Properties of Fully Randomized Biomedical Polyesters Synthesized with a Nontoxic Bismuth(III) Catalyst

“…Polyesters are one of the most significant groups of biodegradable polymers. Homo-, co-, and terpolymers of L-LA, rac -LA, CL, and Gly are widely employed in medicine, e.g., as drug carriers [ 3 , 6 , 39 ]. The advantage of DDSs over traditional drug forms is from controlled and sustained drug release in the body, which is influenced, among other things, by the microstructure of the chain [ 40 ] and the composition of the polymer carrier [ 41 ].…”

“…Among other catalysts considered as non-toxic are Zn- and Zr- based compounds [ 3 ]. Our previous studies have shown that the polymers synthesized in the presence of diethylzinc [ 3 ] and zirconium(IV) acetylacetonate [ 6 ] may be considered as non-toxic in terms of cyto- and genotoxicity and thereby be suitable for pharmaceutical and medical applications.…”