Chemical Composition Of Hydrogels Research Articles

Biointerfacial behavior of stallion spermatozoa adhered to hydrogel surfaces: Impact of the hydrogel chemical composition and the culture medium

Novel soft materials based on hydrogel are proposed to enhance the selection of high-quality stallion sperm based on their adhesion capacity. The hydrogel surfaces are derived from polyacrylamide (PAAm), which is copolymerized with neutral and ionic co-monomers to modify the interfacial properties. The hydrogels undergo characterization through FTIR spectroscopy, assessment of swelling capacity, and wettability under various experimental conditions. Sperm adhesion capacity on the hydrogels is examined through several parameters including the percentage of bound sperm (%Sp) to hydrogels, tail oscillation intensity and flagellar movement. The biointerfacial properties of sperm-hydrogel systems vary based on the chemical composition of hydrogel as well as the components present in the culture medium. High %Sp and excellent metabolic activity of the spermatozoa are observed on hydrogel surfaces that possess moderate hydrophilicity. Specifically, a cationic hydrogel in BGM3 culture medium and a neutral surface in BGM3 medium supplemented with BSA exhibit favorable outcomes. Scanning Electron Microscopy (SEM) reveals the normal morphology of the head and tail in spermatozoa adhered to the hydrogel. Therefore, these hydrogel surfaces are potential materials for selecting stallion sperm with high quality, and their application could be extended to the study of other mammalian reproductive cells.

FEATHER MEAL PREPARATION FROM CHICKEN FEATHERS AND ITS APPLICATION

Feather meal was prepared in powdered form from chicken feather waste, by defatting process. For the overall growth of the wheat crop feather meal used as a bio-fertilizer. In the presence of feather meal, the height of test leaves (39cm), number of wheat plant leaves (T) (213) was found to be increased as compared to standard (36.5cm), (123) respectively, dry weight of plant (T) roots was also improved by 0.8 g. In vivo and in vitro, KS (Keratin azure)-hydrogel and FM (feather meal) hydrogel was prepared and effectively involved in wound healing, tissue aggregation (regeneration). Chemical composition of hydrogel was analyzed by FTIR. Hence, in the present work, environmental non-biodegradable pollutant, i.e. Chicken feathers were positively transformed into eco-friendly valuable product as a bio-fertilizer and therapeutic agent for the wound healing

Synthesis, Swelling Properties and Evaluation of Genotoxicity of Hydrogels Based on (Meth)acrylates and Itaconic Acid

In this study we prepared hydrogels based on 2-hydroxyethyl methacrylate (HEMA): PHEMA homopolymer and two terpolymers of HEMA, itaconic acid (IA) and two poly(alkylene glycol) (meth) acrylates (PAGM): poly(ethylene glycol)6 acrylate (P(HEMA/IA/PAGM1)) and poly(propylene glycol)5 methacrylate (P(HEMA/IA/PAGM2)). Hydrogels were synthesized by gamma-irradiated radical polymerization and subjected to swelling measurements and genotoxicity evaluation. Swelling studies confirmed that these hydrogels deserve consideration as biomaterials due to their ability to swell in phosphate buffer but maintaining physical integrity for a prolonged contact time after equilibrium state has been reached. Comet assay showed certain genotoxic effect following cell exposure to extracts of hydrogels, which was dependent on the concentration of extracts, chemical composition of hydrogels and the degree of crosslinking. The influence of concentration on genotoxicity was the most pronounced. The synthesis of these novel HEMA-based hydrogels should be optimized so as to reduce their toxicity and enable the use in clinical practice.

Development of a new passive sampler based on diffusive milligel beads for copper analysis in water

A new passive sampler was designed and characterized for the determination of free copper ion (Cu2+) concentration in aqueous solution. Each sampling device was composed of a set of about 30 diffusive milligel (DMG) beads. Milligel beads with incorporated cation exchange resin (Chelex) particles were synthetized using an adapted droplet-based millifluidic process. Beads were assumed to be prolate spheroids, with a diameter of 1.6 mm and an anisotropic factor of 1.4. The milligel was controlled in chemical composition of hydrogel (monomer, cross-linker, initiator and Chelex concentration) and characterized in pore size. Two types of sampling devices were developed containing 7.5% and 15% of Chelex, respectively, and 6 nm pore size. The kinetic curves obtained demonstrated the accumulation of copper in the DMG according to the process described in the literature as absorption (and/or adsorption) and release following the Fick's first law of diffusion. For their use in water monitoring, the typical physico-chemical characteristics of the samplers, i.e. the mass-transfer coefficient (k0) and the sampler-water partition coefficient (Ksw), were determined based on a static exposure design. In order to determine the copper concentration in the samplers after their exposure, a method using DMG bead digestion combined to Inductively Coupled Plasma – Atomic Emission Spectrometry (ICP-AES) analysis was developed and optimized. The DMG devices proved to be capable to absorb free copper ions from an aqueous solution, which could be accurately quantified with a mean recovery of 99% and a repeatability of 7% (mean relative uncertainty).

Oxaprozin/poly(2-hydroxyethyl acrylate/itaconic acid) hydrogels: morphological, thermal, swelling, drug release and antibacterial properties

In this study, a series of novel stimuli-sensitive hydrogels based on 2-hydroxyethyl acrylate and itaconic acid monomers were designed for the controlled release of hydrophobic drug, Oxaprozin. All samples were synthesized by the free-radical crosslinking copolymerization and characterized for structural, morphological, thermal, surface charge, swelling and antibacterial properties. In order to investigate the influence of the drug on hydrogel properties the same characterization was conducted for all Oxaprozin-loaded samples. The chemical composition of hydrogels was studied using Fourier transform infrared spectroscopy, while their morphology and thermal properties were examined by scanning electron microscopy and differential scanning calorimetry. Swelling studies, conducted in the physiological pH range from 2.20 to 8.00 and in the temperature range from 25 to 50 °C, showed that the loaded drug does not modify the pH and temperature sensitivity of the hydrogels, but reduces their swelling capacity. The in vitro drug release study conducted at pH 2.20 and 7.40 showed that all hydrogels can be tailored as colon specific drug delivery systems, and the drug release rate can be effectively controlled by IA content. In addition, the antibacterial activity of the hydrogels was determined against Escherichia coli and Staphylococcus aureus, by the zone of inhibition test. Results of our study indicate that these “smart” hydrogels, with specific morphology, surface charge, swelling capacity, drug loading efficiency and release behavior, could be designed to obtain an enhanced and site-specific controlled drug release system by simply adjusting their composition.

Phillipsite‐type synthetic zeolite with high silica contents and accompanying phases

AbstractA zeolite of P type with a molar ratio SiO2 : Al2O3 of about 6 was obtained on laboratory and on enlarged scale, by synthesis carried out at 100°C in Na2OK2OSiO2Al2O3H2O system, without complexing agents. It was found that the products depend not only on the chemical composition of hydrogel but also on the kinetic factors such as: the material of the reactor wall, the amount of substrates taken for crystallization and stiring. It was found that the stability of zeolites increases in the order: L < T < Ch < P. The factors accelerating crystallization led to the more stable zeolites as products. The paper shows difficulties in implementing the laboratory results into an industrial production.