Thiolated chitosan nanoparticles for the nasal administration of leuprolide: Bioavailability and pharmacokinetic characterization

Novel Delivery Systems for Improving the Clinical Use of Peptides

“…Thiolated polymers have been used as potential excipients for the nasal delivery since they are safe, improve residence time on the nasal mucosa, and act as penetration enhancers and enzyme inhibitors (Vetter and Bernkop-Schnurch, 2010;Palmberger et al, 2011). In rats, leuprolide-loaded thiolated chitosan nanoparticles increased the area under the curve (AUC), C max , and elimination half-life after nasal application by 6.9-, 3.8-, and 4-fold, respectively, compared with the solution administration (Shahnaz et al, 2012a). Relative bioavailability was reported to be 19.6%.…”

In vitro dissolution/release methods for mucosal delivery systems

“…The volume of the receptor medium should be adjusted to maintain sink conditions. This approach is applicable if the drug release lasts much longer (in hours) than the particle separation (in minutes) process and is often used to test in vitro drug release from nasal micro-and nano-sized delivery systems [72,74]. As the particle size decreases, the difficulties of separation increase.…”

Design and application of chitosan microspheres as oral and nasal vaccine carriers: an updated review

“…[109][110][111][112][113][114] Among various thiomer-based carriers, thiolated CMs (TCMs) are highly popular because of their strong mucoadhesiveness and ability to control and extend drug release profiles with improved permeation ability. [115][116][117][118][119] TCMs can be prepared by immobilizing the thiol-bearing chain on the polymeric backbone of chitosan ( Figure 3). The strong mucoadhesivity of TCMs is obtained through the formation of disulfide bonds between the thiol groups of TCMs and cysteine-rich subdomains of mucin glycoproteins at the mucosal surface (Figure 4).…”

“…Moreover, TCMs exhibit a reversible opening of the tight junction, which leads to better permeation effects than unmodified CMs. 115,117,120 In the case of first-generation thiomers, thiolated chitosan derivatives are prepared by conjugating thiol-bearing aliphatic ligands to the amino groups of chitosan. For example, N-acetyl-cysteine, 6 form is the main reason that it could become a successful vaccine carrier in the near future.…”