Comparative Analysis of Morphological and Release Profiles in Ocular Implants of Acetazolamide Prepared by Electrospinning

Abstract

The visual impairment that often leads to blindness causes a higher morbidity rate. The goal of this work is to create a novel biodegradable polymeric implant obtained from coaxial fibers containing the dispersed drug—acetazolamide—in order to achieve sustained drug release and increase patient compliance, which is of the highest importance. Firstly, during this work, uncoated implants were produced by electrospinning, and rolled in the shape of small cylinders that were composed of uniaxial and coaxial fibers with immobilized drug inside. The fibers were composed by PCL (poly ε-caprolactone) and Lutrol F127 (poly (oxyethylene-b-oxypropylene-b-oxyethylene)). The prepared implants exhibited a fast rate of drug release, which led to the preparation of new implants incorporating the same formulation but with an additional coating film prepared by solvent casting and comprising PCL and Lutrol F127 or PCL and Luwax EVA 3 ((poly (ethylene-co-vinyl acetate)). Implants were characterized and in vitro release profiles of acetazolamide were obtained in phosphate buffered saline (PBS) at 37 °C. The release profile of the acetazolamide from coated implant containing Luwax EVA 3 is considerably slower than what was observed in case of coated implants containing Lutrol F127, allowing a sustained release and an innovation relatively to other ocular drug delivery systems.

Breaking Barriers in Eye Treatment: Polymeric Nano-Based Drug-Delivery System for Anterior Segment Diseases and Glaucoma

“…Recent DDS studies propose the use of electrospinning biodegradable polymers that are more adaptable and rapidly dissolve in the cornea due to their highly porous structure. Andreadis et al (2022) created an in situ electrospun film gel for the delivery of timolol maleate [ 96 ], and similarly, Morais et al (2021) developed electrospun ocular implants for acetazolamide delivery [ 97 ]. Both showed a significant sustained IOP-lowering effect and increased local delivery.…”

Tunable Spun Fiber Constructs in Biomedicine: Influence of Processing Parameters in the Fibers’ Architecture

“…As a norm, the core flow rate should always be smaller than the shell flow rate, so a complete coverage of the core can be attained and continuous fibers can be formed [22]. Morais et al showed exactly that by generating core-shell fibers with smooth surfaces without irregularities, which indicates that the implant coating surface has an extensive pore network and tubules that completely cover the inner region for a sustainable release of the entrapped drug [79].…”

Recent applications of electrical, centrifugal, and pressurised emerging technologies for fibrous structure engineering in drug delivery, regenerative medicine and theranostics

“…The ES process has also found to be advantageous in developing fibrous mats for novel controlled drug delivery systems via an array of administration routes such as buccal [59,371,372], nasal [373][374][375], transdermal [194,376,377] and ocular [378][379][380][381][382]. ES has found to have the ability to overcome limitations of conventional drug delivery routes of administrations e.g.…”

“…The resulting fibrous coatings showed an increase in drug release; up to 20% more timolol maleate was released from the coatings compared to permeation enhancer-free coatings. More recently, coaxial fibers containing acetazolamide were fabricated to create a novel biodegradable polymeric ocular implant [378]. The PCL based implants exhibited sustained release of the drug following coating of poly (ethylene-co-vinyl acetate), engineering an innovative implant advantageous over existing ocular drug delivery systems.…”