Kinetic model of drug distribution in the urinary bladder wall following intravesical instillation

Formulation Study of Intravesical Oxybutynin Instillation Solution with Enhanced Retention in Bladder

“…Grabnar et al demonstrated that chitosan and polycarbophil applied to intravesical drug delivery increase permeability of the bladder wall. 9) Although in this study there was no significant difference in the OB retention property between OB-0.4% HYA and OB-1.0% HPC in spite of the difference in the adhesion energy in rheological study, this seems to be attributed to a difference in the diffusion behavior of OB by the difference of viscoelastic properties of HYA or HPC. We believe further detailed investigation of the absorption of OB will reveal ways to explain the phenomena observed in this study.…”

“…In the urological field, the application of bioadhesive polymers such as chitosan, polycarbophil, 8,9) poly(methylidene, alonate 2.12) 10) and hydroxypropylcellulose (HPC) have been reported. 11,12) With regard to the OB intravesical instillation, Chiba et al demonstrated that addition of 1.0% HPC effective prolongs OB retention in the bladder.…”

Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan–thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers

“…45 Generally, intravesical chemotherapeutic drugs are applied in catheterized patients by installation of approximately 50 mL (range, 20-60 mL) of formulation. Therefore, in the current study, NP-loaded chitosan and Plx gel formulations were diluted with Tyrode solution were used as artificial urine in a 1:1 ratio to investigate the changes in their properties when they were mixed with urine in the bladder.…”

Intravesical delivery of 5‐aminolevulinic acid from water‐in‐oil nano/submicron‐emulsion systems

“…4,37 The bladder wall is composed of an unperfused transitional epithelium called the urothelium, which represents the toughest known barrier to drug delivery. 10,38 Although the emulsions could not improve ALA permeation at the initial stage of application (1 h) because of the slow release from the inner phase, PpIX accumulation was significantly enhanced after a longer administration duration (3 h). The results of CLSM were consistent with the data of accumulated PpIX extracted from the tissues, which showed a more significant fluorescence in emulsions than in the free form.…”

“…38 The hydrophilic nature of the aqueous droplets of emulsions may have an affinity for GAG, giving the droplets access to the umbrella cell layer. Factors contributing to the increased permeation by the emulsions may be the large surface area, and due to the small droplet size.…”