Physicochemical and release studies of naproxen in poloxamer gels

Signal diffusion and the mitigation of social exploitation in pneumococcal competence signalling

“…To date, all estimates of the spontaneous induction density for transformation have been made in batch culture conditions that facilitate free diffusion of the competence peptide. We modified this critical environmental component, in order to more closely mimic conditions that would prevail during surface or tissue-associated biofilm growth, or growth within microcolonies or mucus, by growing cells in media in which diffusivity was decreased to varying degrees by the co-block polymer Pluronic F127, a solidifying agent for which concentration inversely scales with diffusivity (Gilbert et al 1986;Suh & Jun 1996;Moore et al 2000).…”

“…Pluronic F-127 is a non-toxic, di-block copolymer of polyoxyethlene and polyoxypropylene that exhibits thermoreversible gelling, forming a liquid at temperatures less than 158C and a solid at temperatures greater than 158C Wirtanen et al 1998). The degree of viscosity depends upon the concentration of Pluronic, and diffusion constants of various compounds, proteins and peptides are known to decline log-linearly as a function of the concentration of Pluronic (Gilbert et al 1986;Suh & Jun 1996;Moore et al 2000).…”

Poly(ethylene oxide)–Poly(propylene oxide)-Based Copolymers for Transdermal Drug Delivery: An Overview

“…The release of naproxen from Poloxamer 407 gel across the membrane into isopropyl myristate was dependent on medium pH and was significantly sustained at pH 2, with an inversely proportional to the surfactant concentration [10].…”

“…Studies on PEO-PPO-based polymeric micelles for transdermal drug delivery have been widely carried out with Poloxamer 407 (Pluronic F127) and these studies mostly focused on small drug molecules in order of anti-inflammatory [8][9][10][11][12][13][14][15][16][17][18][19], analgesic [20], local anesthetic [21] and cardiac effectiveness [19,[22][23][24] and rarely focused on big molecules such as arginine vasopressin (AVP) and insulin [25,26].…”

Investigating the ability of nanoparticle-loaded hydroxypropyl methylcellulose and xanthan gum gels to enhance drug penetration into the skin

“…HPMC in contrast is a very weak gel [39] that forms as a consequence of the amphiphilic characteristics of macromolecule chains providing connections between hydrophobic and hydrophilic sites of the polymer. Although adding water to HPMC would reduce its viscosity, like other neutral polymers, it is likely that this gel would allow drug permeation to proceed independently of the gel viscosity because the mesh size of the gel is large and probably would not change much upon dilution [40,41]. As a consequence, in the finite dosing study, the loss of water upon drying on the skin from the HPMC gel and the subsequent increase in viscosity would probably have a very limited effect on the drug permeation behaviour.…”