The Effect of Polymer Microstructure on Encapsulation Efficiency and Release Kinetics of Citropin 1.1 from the Poly(ε-caprolactone) Microparticles

Abstract

Cationic antimicrobial peptides represent a promising therapeutic option against multidrug-resistant bacteria for the treatment of local infections. However, due to their low stability and potential toxicity, there are limited possibilities for their application in clinical practice. In this study, different poly(ε-caprolactone) (PCL) microparticles (MPs) loaded with citropin 1.1 (CIT) were investigated in order to demonstrate the effect of the polymer microstructure on the encapsulation efficiency (EE) and kinetics of the peptide release from the newly developed devices. The characteristics of the new systems in terms of surface morphology, particle size, EE and zeta potential analysis, as well as the haemolytic activities of the peptide were investigated. The in vitro release kinetics of CIT from the MPs was also investigated. CIT loading was favoured by a high content of negative charged linear polymer chains in the PCL structure. The presence of non-charged, amorphous macrocycle domains results in faster degradation of the PCL matrix. Depending on the crystallinity of the PCL, the peptide release exhibited a near-zero-order or near-first-order profile with no “burst release”. The results indicated that CIT-loaded PCL MPs could potentially be a promising drug delivery system (DDS) for the treatment of local infections.

Susceptibility of microbial cells to the modified PIP2-binding sequence of gelsolin anchored on the surface of magnetic nanoparticles

“…Due to this fact, significant efforts and different strategies have been engaged in the past decades to protect AMPs from degradation, inactivation and to improve their biocompatibility including by substitution with unnatural amino acids, d -amino acids, W or end-caps, varying chain length, cyclization or polymerization [43–45]. Another approach to increasing clinical use is through increasing stability and by decreasing their toxicity through the use of drug carriers [46]. Our previous studies have shown that both physical and covalent immobilization on the nanoparticle surface markedly enhances the activity of AMPs and their chemical analogs [23, 47].…”

Targeting Multidrug Resistance With Antimicrobial Peptide-Decorated Nanoparticles and Polymers

“…In addition, many polymeric nanoparticles are bio-degradable and cleared through metabolic pathways in the bodies ( Chan et al, 2010 ). Moreover, to facilitate the local administration and the release rate, the polymeric nanoparticles that are conjugated with peptides have been shown to demonstrate near-first-order or near-zero distribution without burst release; as a result, it has emerged as a promising system of drug delivery to treat local infections ( Piotrowska et al, 2018 ). This was further exemplified by the application of multi-polymers, such as a combined use of chitosan and polyethylene glycol, a procedure that has been shown to decrease the propensity to aggregate and make the nanoparticles more stable and biocompatible ( Calvo et al, 1997 ).…”

Fabrication and Characterization of a Novel Herbicide Delivery System with Magnetic Collectability and Its Phytotoxic Effect on Photosystem II of Aquatic Macrophyte

“…46 For instance, Grillo and colleagues developed PCL nanopesticides containing atrazine and obtained a release exponent (n) of 0.92, indicating that the system is also controlled by non-Fickian diffusion. 21 Other PCL microparticles with different active ingredients (e.g., cationic antimicrobial peptides, 48 nonsteroidal anti-inflammatory drug, 49 antihypertensive therapy 50 ) have shown a similar diffusion process.…”