Chemical Modification of Hyaluronic Acid for Intraoral Application

Permeation Enhancement via Thiolation: In Vitro and Ex Vivo Evaluation of Hyaluronic Acid-Cysteine Ethyl Ester

“…Moreover, IR spectra reflected the succeeded synthesis of thiolated HA. The characteristic peaks such as 3161 and 3159 cm −1 representing the C‐H stretch as well as the N‐H bend and ‐C=C‐ were shown at 1653–1619 cm −1 . Furthermore, the proving for the succeeded amide bond formation was found in HAC with 1735–1700 cm −1 , whereas it could not be detected for unmodified HA as shown in Figures a (HA) and b (HAC).…”

Liver-targeting self-assembled hyaluronic acid-glycyrrhetinic acid micelles enhance hepato-protective effect of silybin after oral administration

“…Among them, hyaluronic acid (HA), a non-toxic, biocompatible and biodegradable polysaccharide, has gained intense attention due to its potential as drug delivery carrier (Almeida et al, 2014;Laffleur et al, 2014;Liu et al, 2015). Many studies have reported that HA receptors in human body played important biological roles, such as endocytosis, degradation and signal transduction (Oh et al, 2010).…”

Thiolated Hyaluronic Acid as Versatile Mucoadhesive Polymer: From the Chemistry Behind to Product Developments—What Are the Capabilities?

“…The biocompatibility represents an important issue within formulation development from the academic as well as the industrial point of view, as novel formulations should not cause adverse effects after administration. Within several studies from Laffleur and co-workers, thiolated HA did not affect cell viability of Caco-2 cells [16,19,20,21,22,23]. Moreover, other research groups demonstrated high cell viability on 3T3, RAW 264.7 and HMEC cells [67].…”

“…Recently, Laffleur et al [23] demonstrated that thiolation of HA leads to an even 12-fold augmentation in mucoadhesion on buccal mucosa. Thiolated HA preactivated with 6-mercaptonicotinamide demonstrated a 4-fold improved adhesion time compared to thiolated HA [19]. These findings are based on the formation of covalent bonds between thiol groups of thiolated HA and cysteine-rich domains within the mucin glycoproteins [65,66].…”

“…For example, HA-cysteine ethyl ester exhibited 3.5-fold improved swelling capacity compared to the unmodified polymer [23]. Laffleur et al [19] mentioned recently that it is not mandatory to reach the maximum swelling capacity in order to take the advantage of thiolated polymers. On the contrary, to overcome the worrying bottleneck of biodegradability, a balance between swelling and stability should be guaranteed.…”