Psoriasis is a chronic autoimmune systemic disease with an approximate incidence of 2% worldwide; it is commonly characterized by squamous lesions on the skin that present the typical pain, stinging, and bleeding associated with an inflammatory response. In this work, poly(methyl vinyl ether-alt-maleic ethyl monoester) (PMVEMA-ES) nanofibers have been designed as a delivery vehicle for three therapeutic agents with palliative properties for the symptoms of this disease (salicylic acid, methyl salicylate, and capsaicin). For such a task, the production of these nanofibers by means of the electrospinning technique has been optimized. Their morphology and size have been characterized by optical microscopy and scanning electron microscopy (SEM). By selecting the optimal conditions to achieve the smallest and most uniform nanofibers, approximate diameters of up to 800–900 nm were obtained. It was also determined that the therapeutic agents that were used were encapsulated with high efficiency. The analysis of their stability over time by GC-MS showed no significant losses of the encapsulated compounds 15 days after their preparation, except in the case of methyl salicylate. Likewise, it was demonstrated that the therapeutic compounds that were encapsulated conserved, and even improved, their capacity to activate the transient receptor potential cation channel 1 (TRPV1) channel, which has been associated with the formation of psoriatic lesions.

Recent advances in the field of nanotechnology such as nanoencapsulation offer new biomedical applications, potentially increasing the scope and efficacy of therapeutic drug delivery. In addition, the discovery and development of novel biocompatible polymers increases the versatility of these encapsulating nanostructures, enabling chemical properties of the cargo and vehicle to be adapted to specific physiological requirements. Here, we evaluate the capacity of various polymeric nanostructures to encapsulate various antibiotics of different classes, with differing chemical structure. Polymers were sourced from two separate derivatives of poly(methyl vinyl ether-alt-maleic anhydride) (PMVE/MA): an acid (PMVE/MA-Ac) and a monoethyl ester (PMVE/MA-Es). Nanoencapsulation of antibiotics was attempted through electrospinning, and nanoparticle synthesis through solvent displacement, for both polymers. Solvent incompatibilities prevented the nanoencapsulation of amikacin, neomycin and ciprofloxacin in PMVE/MA-Es nanofibers. However, all compounds were successfully loaded into PMVE/MA-Es nanoparticles. Encapsulation efficiencies in nanofibers reached approximately 100% in all compatible systems; however, efficiencies varied substantially in nanoparticles systems, depending on the tested compound (14%–69%). Finally, it was confirmed that both these encapsulation processes did not alter the antimicrobial activity of any tested antibiotic against Staphylococcus aureus and Escherichia coli, supporting the viability of these approaches for nanoscale delivery of antibiotics.

In this study, we employed the copolymer poly(methyl vinyl ether-alt-maleic monoethyl ester) (PMVEMA-Es) and three fluorene-based cationic conjugated polyelectrolytes to develop fluorescent nanoparticles with emission in the blue, green and red spectral regions. The size, Zeta Potential, polydispersity, morphology, time-stability and fluorescent properties of these nanoparticles were characterized, as well as the nature of the interaction between both PMVEMA-Es and fluorescent polyelectrolytes. Because PMVEMA-Es contains a carboxylic acid group in its structure, the effects of pH and ionic strength on the nanoparticles were also evaluated, finding that the size is responsive to pH and ionic strength, largely swelling at physiological pH and returning to their initial size at acidic pHs. Thus, the developed fluorescent nanoparticles can be categorized as pH-sensitive fluorescent nanogels, since they possess the properties of both pH-responsive hydrogels and nanoparticulate systems. Doxorubicin (DOX) was used as a model drug to show the capacity of the blue-emitting nanogels to hold drugs in acidic media and release them at physiological pH, from changes in the fluorescence properties of both nanoparticles and DOX. In addition, preliminary studies by super-resolution confocal microscopy were performed, regarding their potential use as image probes.

Poly(methyl vinyl ether-alt-maleic anhydride) (PMVEMA) of 119 and 139 molecular weights (P119 and P139, respectively) were electrospun to evaluate the resulting fibers as a topical delivery vehicle for (L-)menthol. Thus, electrospinning parameters were optimized for the production of uniform bead-free fibers from 12% w/w PMVEMA (±2.3% w/w menthol) solutions, and their morphology and size were characterized by field emission scanning electron microscopy (FESEM). The fibers of P119 (F₁₁₉s) and P139 (F₁₃₉s) showed average diameter sizes of approximately 534 and 664 nm, respectively, when unloaded, and 837 and 1369 nm when loaded with menthol. The morphology of all types of fibers was cylindrical except for F₁₃₉s, which mostly displayed a double-ribbon-like shape. Gas chromatography-mass spectrometry (GC-MS) analysis determined that not only was the menthol encapsulation efficiency higher in F₁₃₉s (92% versus 68% in F₁₁₉s) but also that its stability over time was higher, given that in contrast with F₁₁₉s, no significant losses in encapsulated menthol were detected in the F₁₃₉s after 10 days post-production. Finally, in vitro biological assays showed no significant induction of cytotoxicity for any of the experimental fibers or in the full functionality of the encapsulated menthol, as it achieved equivalent free-menthol levels of activation of its specific receptor, the (human) transient receptor potential cation channel subfamily M (melastatin) member 8 (TRPM8).

Background/Objectives: The local release of antineoplastic drugs in post-surgical treatments is an alternative way to improve their effectiveness against glioblastoma reappearance. Thus, it was proposed to develop a local delivery system based on electrospun PMVEMA-derived nanofibers for the administration of carmustine (BCNU), temozolomide (TMZ), and doxorubicin (DOX). Methods: Electrospun nanofibers were prepared using PMVEMA-monoethyl ester (PMVEMA-Es) and PMVEMA-acid (PMVEMA-Ac), loading BCNU, TMZ, and DOX at 1% or 8% (w/w). Their morphology, encapsulation efficiency, and release profiles were characterized by FESEM, confocal microscopy, and HPLC. Their biological effects were evaluated through cell viability, cell cycle, and intracellular accumulation assays in established cell lines from glioblastoma patients (HGUE-GB) and human astrocytes (HAs). Results: The nanofibers were optimized without defects, and encapsulation efficiencies were above 80%. The release studies showed a rapid initial release in the first hour, being DOX > TMZ > BCNU, while the second release rate was sustained in the cases of PMVEMA-Ac/TMZ (0.14%/h) and PMVEMA-Es/BCNU (1.2%/h), highlighting that, after 24 h under physiological conditions, the degradation of the loaded drug was lower than its free state, comparable to the Gliadel release system. Furthermore, it was confirmed that there was a dose-dependent decrease in cell viability for PMVEMA-Es/BCNU and PMVEMA-Ac/DOX, with higher cytotoxicity than free DOX. Finally, the lowest concentration tested had a relatively low effect on HAs compared with its effect on glioblastoma cells. Conclusion: PMVEMA-based electrospun nanofibers are effective in encapsulating and releasing antineoplastic drugs, suggesting their potential as a local delivery system to improve glioblastoma post-surgical treatment efficacy.