Controlled release behavior of zinc-loaded carboxymethyl cellulose and carrageenan hydrogels and their effects on wheatgrass growth

Akalın, Gülen Oytun ( Aksaray, Yazar )Sodium carboxymethyl cellulose (NaCMC) and carrageenan (CG) hydrogels were synthesized for potential use in the growth of wheatgrass plant. The water absorbency and gel content properties of prepared hydrogels were investigated. Water absorbency was reduced with increasing the amounts of polymer and crosslinker, in contrast with gel content results. The treatment of hydrogels with soil enhanced the water retention capacity of soil. Zinc micronutrient was loaded in both hydrogels by classic entrapment method. The zinc release behavior of hydrogels in water and soil were determined and the release rate decreased with high gel content and crosslinking density. The influence of zinc-loaded hydrogel on the wheatgrass plant performance were also investigated by using pot experiments. The growth of the wheatgrass (Triticum aestivum) was obviously increased by the use of zinc-loaded hydrogels. The increase in plant performance by using these hydrogels suggests that prepared hydrogels can be used as a controlled fertilizer system in agriculture fields

Preparation and characterization of nanoporous sodium carboxymethyl cellulose hydrogel beads

WOS: 000431221900001A series of nanoporous sodium carboxymethyl cellulose (NaCMC) hydrogel beads were prepared using FeCl3 ionic crosslinker by changing polymer and crosslinker percentages (%). Characteristics of the hydrogels were investigated by gel content, swelling test, degradation test, Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR), Scanning Electron Microscope/Energy Dispersive X-ray Analysis (SEM/EDX), and Atomic Force Microscopy (AFM). Swelling experiments were studied by changing time, temperature, and pH. The swelling percentage (S%) regularly decreased with increasing the amounts of polymer and crosslinker, in contrast with gel content results. NaCMC hydrogels were found to be sensitive to pH variations. The degradation test showed that hydrogels had good stability and their degradation period varied from 30 to 36 days. According to SEM analysis, NaCMC hydrogels had mostly nanoporous structure. The average granule and pore sizes of the least swollen NaCMC-12 hydrogel were found to be 13.1 +/- 0.3nm and 82.1 +/- 3.2 nm. The elemental compositions of hydrogels were determined with EDX. The minimum average surface roughness (R-a) and root mean square roughness (R-ms) parameters were found to be 15.7 +/- 1.9nm and 20.3 +/- 2.2nm for NaCMC-12 hydrogels by AFM. Due to their good morphologies, stabilities, and swelling behaviors, NaCMC hydrogels can be suitable for biomaterial applications.Scientific Research Projects Coordination Unit of Gazi University [05/2015-08]This work was financially supported by the Scientific Research Projects Coordination Unit of Gazi University (Grant no. 05/2015-08)

Preparation and characterization of K-carrageenan hydrogel for controlled release of copper and manganese micronutrients

A series of ?-carrageenan (?-CG) hydrogels were prepared by using glutaraldehyde (GA) as crosslinker for controlled releasing of copper and manganese micronutrients. The hydrogels were characterized by gel content, swelling and degradation tests, Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Scanning Electron Microscope (SEM) observations. The variations of swelling percentages (S%) with time, temperature and pH were determined for all hydrogels. As the amounts of crosslinker increased, S% decreased regularly in contrast to gel content results. The higher swelling values were obtained in basic medium than acidic and neutral mediums for all ?-CG hydrogels. Releasing of copper and manganese micronutrients from ?-CG hydrogels was investigated in water and soil. A simulated releasing model was also applied to estimate the releasing behaviors in agricultural irrigations. In all release studies, the cumulative release values increased with decreasing GA amounts. The release kinetic parameters were also calculated. It was detected that the releasing of micronutrients in soil was slower than that in water. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature

Preparation and Characterization of Nanoporous Sodium Carboxymethyl Cellulose Hydrogel Beads

A series of nanoporous sodium carboxymethyl cellulose (NaCMC) hydrogel beads were prepared using FeCl3 ionic crosslinker by changing polymer and crosslinker percentages (\%). Characteristics of the hydrogels were investigated by gel content, swelling test, degradation test, Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR), Scanning Electron Microscope/Energy Dispersive X-ray Analysis (SEM/EDX), and Atomic Force Microscopy (AFM). Swelling experiments were studied by changing time, temperature, and pH. The swelling percentage (S\%) regularly decreased with increasing the amounts of polymer and crosslinker, in contrast with gel content results. NaCMC hydrogels were found to be sensitive to pH variations. The degradation test showed that hydrogels had good stability and their degradation period varied from 30 to 36 days. According to SEM analysis, NaCMC hydrogels had mostly nanoporous structure. The average granule and pore sizes of the least swollen NaCMC-12 hydrogel were found to be 13.1 +/- 0.3nm and 82.1 +/- 3.2 nm. The elemental compositions of hydrogels were determined with EDX. The minimum average surface roughness (R-a) and root mean square roughness (R-ms) parameters were found to be 15.7 +/- 1.9nm and 20.3 +/- 2.2nm for NaCMC-12 hydrogels by AFM. Due to their good morphologies, stabilities, and swelling behaviors, NaCMC hydrogels can be suitable for biomaterial applications

5-Fluorouracil Encapsulated Chitosan Nanoparticles for pH-Stimulated Drug Delivery: Evaluation of Controlled Release Kinetics

Nanoparticles consisting of human therapeutic drugs are suggested as a promising strategy for targeted and localized drug delivery to tumor cells. In this study, 5-fluorouracil (5-FU) encapsulated chitosan nanoparticles were prepared in order to investigate potentials of localized drug delivery for tumor environment due to pH sensitivity of chitosan nanoparticles. Optimization of chitosan and 5-FU encapsulated nanoparticles production revealed 148.8±1.1 nm and 243.1±17.9 nm particle size diameters with narrow size distributions, which are confirmed by scanning electron microscope (SEM) images. The challenge was to investigate drug delivery of 5-FU encapsulated chitosan nanoparticles due to varied pH changes. To achieve this objective, pH sensitivity of prepared chitosan nanoparticle was evaluated and results showed a significant swelling response for pH 5 with particle diameter of ∼450 nm. In vitro release studies indicated a controlled and sustained release of 5-FU from chitosan nanoparticles with the release amounts of 29.1–60.8% due to varied pH environments after 408 h of the incubation period. pH sensitivity is confirmed by mathematical modeling of release kinetics since chitosan nanoparticles showed stimuli-induced release. Results suggested that 5-FU encapsulated chitosan nanoparticles can be launched as pH-responsive smart drug delivery agents for possible applications of cancer treatments