Controlled and time‐scheduled drug delivery: Polyanhydride‐based nanoparticles as ocular medication carriers

Abstract

Nanoparticles offer an ideal opportunity for the efficient local anesthetic drug delivery required during and after ocular procedures. Currently available local anesthetic drugs are short acting, which may prevent adequate ocular pain control. Therefore, development of sustained controlled release anesthetic devices for pain control over a relatively short period (up to 48 h) potentially meets various opthalmological analgesic requirements. This study presents preliminary findings for drug delivery using poly(sebacic acid) (PSA) nanoparticles for tetracaine and lidocaine administration.Tetracaine-or lidocaine-loaded PSA nanoparticles were prepared using a double emulsion methodology. Release profiles were similar for both formulations, with 50% cumulative release achieved after 17 h and 23 h for tetracaine and lidocaine, respectively.The release profiles were studied, and data obtained from in vitro experiments were fit to different mathematical models. Based on mathematical models used in this study, drug release from all PSA-based formulations was diffusion-controlled, best described by the Higuchi model. Based on preliminary experiments, a hybrid formulation providing a burst effect was designed to counter the fast adsorption of drug expected in the physiological system. This was achieved by coating the lidocaine-loaded PSA nanoparticles with a gelatin/lidocaine layer. The coating provided accelerated lidocaine release, with 50% cumulative release obtained as early as 7 h compared to 23 h for uncoated nanoparticles. This formulation provided a triphasic release that can treat different pain levels at predetermined timelines. Our results provide new insight into the benefits of using polyanhydrides as a platform for drug delivery in ophthalmology.

Development of gelatin nanoparticles for the treatment of pathologies caused by Paraccocideoides brasiliensis

“…For P. brasiliensis yeasts, isolate 18 (Pb18), the antifungal activity of Amphotericin B preparations were similar at concentrations of 1.0 mg.mL -1 and 1.5 mg.mL -1 . However, nanostructured amphotericin B showed more effective antifungal activity at a concentration of 0.5 mg.mL -1 (18 mm halo) when compared to pure Amphotericin B (7 mm halo) which did not reach the considered halo size effective in the literature (Sheskin et al, 2021). At the concentration of 2.0 mg.mL -1 nanostructured amphotericin B, it also showed an important difference in the measurement of the halo, figure 7, when compared with pure amphotericin B on yeasts of Pb18, 20 mm and 17 mm, respectively.…”

“…The formulation produced a biphasic AB release profile with an initial burst effect in which the AB release varied between 34% at the first sampling time (24 h) for NPG-AB. This rapid release is related to the AB adsorbed on the surface of the nanoparticles (Sheskin et al, 2021) and/or to the release of the drug encapsulated near the surface of the nanoparticles.…”