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This study introduces a novel approach utilizing a temporary drug-eluting hydrogel corneal patch to prevent neovascularization, alongside a numerical predictive tool for assessing the release and transport kinetics of bevacizumab (BVZ) after the keratoplasty. A key focus was investigating the impact of tear film clearance on the release kinetics and drug transport from the designed corneal patch. The proposed tear drug clearance model incorporates the physiological mechanism of lacrimal flow (tear turnover), distinguishing itself from previous models. Validation against experimental data confirms the model's robustness, despite limitations such as a 2D axisymmetrical framework and omission of blink frequency and saccadic eye movements potential effects. Analysis highlights the significant influence of lacrimal flow on ocular drug transport, with the corneal patch extending BVZ residence time compared to topical administration. This research sets the stage for exploring multi-layer drug-eluting corneal patches as a promising therapeutic strategy in ocular health., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Ventilator-associated pneumonia (VAP) remains one of the most common hospital-acquired infections (HAI). Considering the complicated diagnosis and the lack of effective treatment, prophylactic measures are suggested as the new standard to prevent the disease. Although VAP often manifests a polymicrobial nature, Pseudomonas aeruginosa remains one of the pathogens associated with the highest morbidity and mortality rates within these mechanically ventilated patients. In this paper, we report on the development of an antibacterial hydrogel coating using the polymyxin B (PMB) peptide to prevent bacterial adhesion to the polymeric substrate. We fully characterized the properties of the coating using atomic force microscopy (AFM), scanning electron microscopy (SEM), wettability analyses and Fourier-transform infrared (FTIR) and Raman spectroscopy. Furthermore, several biological assays confirmed the antibacterial and anti-biofilm effect of the tubing for at least 8 days against P. aeruginosa . On top of that, the produced coating is compliant with the requirements regarding cytocompatibility stated in the ISO (International Organization for Standardization) 10993 guidelines and an extended release of PMB over a period of at least 42 days was detected. In conclusion, this study serves as a foundation for peptide-releasing hydrogel formulas in the prevention of VAP.

Intravitreal administrated bevacizumab has emerged as an effective antibody for suppressing VEGF expression in age-related macular degeneration (AMD) therapy. This study discusses certain issues related to the sustained release of bevacizumab from intravitreal poly(lactic-co-glycolic acid) (PLGA) microspheres. A computational model elucidating the ocular kinetics of bevacizumab is demonstrated, wherein the release of the drug from PLGA microspheres is modeled using the Koizumi approach, complemented by an empirical model that links the kinetics of bevacizumab release to a size-dependent hydrolytic degradation of the drug-loaded polymeric microparticles. The results of the simulation were then rigorously validated against experimental data. The as-developed model proved remarkably accurate in predicting the time-concentration profiles obtained following the intravitreal injection of PLGA microspheres of significantly different sizes. Notably, the time-concentration profiles of bevacizumab in distinct ocular tissues were almost unaffected by the size of the intravitreally administered PLGA microparticles. Furthermore, the model successfully predicted the retinal concentration of bevacizumab and its fragments (e.g., ranibizumab) administrated in the form of a solution. As such, this model for drug sustained release and ocular transport holds tremendous potential for facilitating the reliable evaluation of planned anti-VEGF therapies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

In this paper, the effect of the presence of L929 fibroblast cells and a cyclic load application on the kinetics of the degradation of amorphous PLGA films was examined. Complex micro and nano morphological, mechanical and physico-chemical studies were performed to assess the degradation of the tested material. For this purpose, molecular weight, glass transition temperature, specimen morphology (SEM, μCT) and topography (AFM) as well as the stiffness of the material were measured. The study showed that the presence of living cells along with a mechanical load accelerates the PLGA degradation in comparison to the degradation occurring in acellular media: PBS and DMEM. The drop in molecular weight observed was accompanied by a distinct increase in the tensile modulus and surface roughness, especially in the case of the film degradation in the presence of cells. The suspected cause of the rise in stiffness during the degradation of PLGA films is a reduction in the molecular mobility of the distinctive superficial layer resulting from severe structural changes caused by the surface degradation. In conclusion, all the micro and nanoscale properties of amorphous PLGA considered in the study are sensitive to the presence of L929 cells, as well as to a cyclic load applied during the degradation process., (Copyright © 2018 Elsevier Ltd. All rights reserved.)