Pulsatile Discharge from Polymeric Scaffolds: A Novel Method for Modulated Drug Release

Abstract

Controlled drug release holds promise to revolutionize medicine, particularly if short-term and long-term release can be combined in a single system. We present here a new pulsatile release system, in which the pulses were achieved using 3D scaffolds of poly(l-lactic acid), PLLA. From a morphological characterization of the scaffold’s surfaces, before and after releasing experiments at distinct pHs, we infer that release is governed by electrostatic interactions and the fractal geometry of the scaffolds. Furthermore, the scaffold can present short-term (within hours) or long-term (several days long) releasing profiles by varying the pH, which opens the way for unprecedented drug release control.

Review: Syntheses of poly(lactic acid)s and their block copolymers for drug delivery applications

“…as PLA nanofibers loaded with the chemotherapeutic molecule paclitaxel and C 70 water-soluble fullerenes, 26 as PLA/PEO electrospun fibres for protein delivery 27 and as PLA 3D porous scaffolds for sustained protein release controlled by pH. 28 Syntheses of poly(lactic acid)s and poly(lactide)s and their monomers There are two main options with respect to the synthesis of PLA, namely direct polycondensation of lactic acid and the ROP of lactides using a suitable catalyst. 29 It should be stated that so-called green processes, i.e.…”

“…The mechanical performance and physical properties of PLA, combined with its high degree of biocompatibility, mean that it is particularly well placed for use in a wide variety of drug delivery systems, e.g. as PLA nanofibers loaded with the chemotherapeutic molecule paclitaxel and C 70 water‐soluble fullerenes, 26 as PLA/PEO electrospun fibres for protein delivery 27 and as PLA 3D porous scaffolds for sustained protein release controlled by pH 28 …”

Bacterial Photoinactivation Using PLGA Electrospun Scaffolds

“…In applications where the surfaces come into contact with human bodies, as in implants and medical devices, antimicrobial materials may be used jointly with polymers such as poly­(lactic acid) and poly­( l -lactic acid) (PLLA), poly­[lactic- co -(glycolic acid)] (PLGA), and poly­(caprolactone) (PCL). PLA and PLLA have been used in tissue engineering as nanofiber membranes to enhance cell growth , and proliferation and pulsatile drug-delivery systems . PCL has been employed in biomaterials since the 1970s as a drug-delivery device, and later on in tissue engineering as formulations as microspheres, nanoparticles, films, micelles, and scaffolds .…”

“…PLA and PLLA have been used in tissue engineering as nanofiber membranes to enhance cell growth 21,22 and proliferation 23 and pulsatile drug-delivery systems. 24 PCL has been employed in biomaterials since the 1970s as a drugdelivery device, 25 and later on in tissue engineering as formulations as microspheres, nanoparticles, films, micelles, 26 and scaffolds. 27 PLGA has been used in tissue engineering and drug release, as in the release of anticancer agents, 28,29 vaccines, and cancer immunotherapeutics.…”