Effect of crosslinking strategy on the biological, antibacterial and physicochemical performance of hyaluronic acid and ɛ-polylysine based hydrogels

Calcium Phosphate/Hyaluronic Acid Composite Hydrogels for Local Antiosteoporotic Drug Delivery

“…After identifying LVER in the amplitude sweep experiment, the frequency sweep test was carried out at 0.2% shear strain. The BDDE crosslinked hydrogels showed behavior similar to the previously reported chemically crosslinked HA hydrogels ( Gu et al, 2017 ; Salma-Ancane et al, 2022 ), where G′ is constant across all the frequency ranges ( Figures 6C, D ), thus demonstrating solid-like and stable inner structure. However, HA H, HA H_SrRan, Mech_HA/CaP_H, and Synt_HA/CaP_H exhibited a decrease in G″ modulus at frequencies higher than 60 Hz, possibly due to the breakage of the samples or due to the limitations of the system measurements for G″, which don’t have the same range as the G′ ( Figures 6C, D ).…”

“…Additionally, the storage modulus was extracted from the frequency sweeps [an approach used previously for both physically and chemically crosslinked hydrogels ( Wychowaniec et al, 2020 ; Salma-Ancane et al, 2022 )], thus evaluating the mechanical stiffness of all lyophilized hydrogels ( Figure 6E ). As expected from the observed gel fraction results, Mech_HA/CaP_H exhibited a significantly higher storage modulus value (42 ± 9 kPa) than Synt_HA/CaP_H (21 ± 2 kPa) and HA H (2 ± 0.4 kPa).…”

Fabrication of hydrogel microspheres via microfluidics using inverse electron demand Diels–Alder click chemistry-based tetrazine-norbornene for drug delivery and cell encapsulation applications

“…No apparent signs of volume changes or signs of degradation were observed based on the obtained images, following similar iEDDA-crosslinked PEG-based formulations with prolonged hydrolytic stability 65,66 and similarly to poly- l -ornithine-coated alginate MPs, which own swelling index values below 0.75 under the same conditions. 67–70 However, at pH 5.5, both formulations showed a different behaviour, characterized by a gradual increase in their swelling index until the complete degradation of the MPs, only observed after 8 days. Major differences were observed between formulations with either 10% or 20% of 4-arm PEG-TZ concentration, leading to an increase in the swelling index values for the formulations with lower polymer content.…”

A Safe-by-Design Approach for the Synthesis of a Novel Cross-Linked Hyaluronic Acid with Improved Biological and Physical Properties

“…The cross-linking of polymers with hydrophilic characteristics, such as HA, has made it possible to obtain elastic and deformable structures called hydrogels. The high degree of swelling that characterizes hydrogels has been shown to be closely related to parameters such as the structure and the degree of cross-linking [ 27 ].…”