53 research outputs found
Modulation of release kinetics by plasma polymerization of ampicillin-loaded Ă-TCP ceramics
Beta-tricalcium phosphate (Ă-TCP) bioceramics are employed in bone repair surgery. Their local implantation in bone defects puts them in the limelight as potential materials for local drug delivery. However, obtaining suitable release patterns fitting the required therapeutics is a challenge. Here, plasma polymerization of ampicillin-loaded Ă-TCP is studied for the design of a novel antibiotic delivery system. Polyethylene glycol-like (PEG-like) coating of Ă-TCP by low pressure plasma polymerization was performed using diglyme as precursor, and nanometric PEG-like layers were obtained by simple and double plasma polymerization processes. A significant increase in hydrophobicity, and the presence of plasma polymer was visible on the surface by SEM and quantified by XPS. As a main consequence of the plasma polymerisation, the release kinetics were successfully modified, avoiding burst release, and slowing down the initial rate of release leading to a 4.5Âżh delay in reaching the same antibiotic release percentage, whilst conservation of the activity of the antibiotic was simultaneously maintained. Thus, plasma polymerisation on the surface of bioceramics may be a good strategy to design controlled drug delivery matrices for local bone therapiesPeer ReviewedPostprint (author's final draft
White paper on the future of plasma science and technology in plastics and textiles
This is the peer reviewed version of the following article: âUros, C., Walsh, J., CernĂĄk, M., Labay, C., Canal, J.M., Canal, C. (2019) White paper on the future of plasma science and technology in plastics and textiles. Plasma processes and polymers, 16 1 which has been published in final form at [doi: 10.1002/ppap.201700228]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."This white paper considers the future of plasma science and technology related to the manufacturing and modifications of plastics and textiles, summarizing existing efforts and the current stateâofâart for major topics related to plasma processing techniques. It draws on the frontier of plasma technologies in order to see beyond and identify the grand challenges which we face in the following 5â10 years. To progress and move the frontier forward, the paper highlights the major enabling technologies and topics related to the design of surfaces, coatings and materials with nonâequilibrium plasmas. The aim is to progress the field of plastics and textile production using advanced plasma processing as the key enabling technology which is environmentally friendly, cost efficient, and offers highâspeed processingPeer ReviewedPostprint (author's final draft
Modification of hydrogel-based biomaterials by atmospheric pressure plasma to enhance tissue regeneration
Postprint (published version
Generation of reactive species by plasma needle in different lĂquids
Postprint (published version
Tyrosinase-loaded Multicompartment Microreactor toward Melanoma Depletion
Melanoma is malignant
skin cancer occurring with increasing prevalence
with no effective treatment. A unique feature of melanoma cells is
that they require higher concentrations of ltyrosine (l-tyr) for expansion than normal cells. As such, it has been
demonstrated that dietary l-tyr restriction lowers systemic l-tyr and suppresses melanoma advancement in mice. Unfortunately,
this diet is not well tolerated by humans. An alternative approach
to impede melanoma progression will be to administer the enzyme tyrosinase
(TYR), which converts l-tyr into melanin. Herein, a multicompartment
carrier consisting of a polymer shell entrapping thousands of liposomes
is employed to act as a microreactor depleting l-tyr in the
presence of melanoma cells. It is shown that the TYR enzyme can be
incorporated within the liposomal subunits with preserved catalytic
activity. Aiming to mimic the dynamic environment at the tumor site, l-tyr conversion is conducted by co-culturing melanoma cells
and microreactors in a microfluidic setup with applied intratumor
shear stress. It is demonstrated that the microreactors are concurrently
depleting l-tyr, which translates into inhibited melanoma
cell growth. Thus, the first microreactor where the depletion of a
substrate translates into antitumor properties in vitro is reported
Biocompatible vehicles for RONS generated by atmospheric plasmas in liquids
Postprint (published version
Investigating the atmospheric pressure plasma jet modification of a photo-crosslinkable hydrogel
Atmospheric pressure plasma jets (APPJ) have great potential in wound healing, bacterial disinfection and in cancer therapy. Recent studies pointed out that hydrogels can be used as screens during APPJ treatment, or even be used as reservoirs for reactive oxygen and nitrogen species generated by APPJ in liquids. Thus, novel applications are emerging for hydrogels which deserve fundamental exploration of the possible modifications undergone by the polymers in solution due to the reactivity with plasmas. Here we investigate the possible modifications occurred by APPJ treatment of an amphiphilic poly(ethylene oxide)-based triblock copolymer (tPEO) photo-crosslinkable hydrogel. While APPJ treatments lead to a certain degradation of the self-assembly of the polymeric chains at low concentrations (2 g/L), the polymeric chains are unaffected by APPJ and the hydrogel forming ability is kept. APPJ treatments induced a pre-crosslinking of the network with an increase of the mechanical properties of the hydrogel. Overall, the small modifications induced allow thinking of polymer solutions with hydrogel forming ability a new platform for several applications related to plasma medicine, and thus, with potential in different therapies.Postprint (author's final draft
Important parameters in plasma jets for the production of RONS in liquids for plasma medicine: A brief review
Reactive oxygen and nitrogen species (RONS) are among the key factors in plasma medicine. They are generated by atmospheric plasmas in biological fluids, living tissues and in a variety of liquids. This ability of plasmas to create a delicate mix of RONS in liquids has been used to design remote or indirect treatments for oncological therapy by treating biological fluids by plasmas and putting them in contact with the tumour. Documented effects include selective cancer cell toxicity, even though the exact mechanisms involved are still under investigation. However, the ârightâ dose for suitable therapeutical activity is crucial and still under debate. The wide variety of plasma sources hampers comparisons. This review focuses on atmospheric pressure plasma jets as the most studied plasma devices in plasma medicine and compiles the conditions employed to generate RONS in relevant liquids and the concentration ranges obtained. The concentrations of H2O2, NO2-, NO3- and short-lived oxygen species are compared critically to provide a useful overview for the readerPeer ReviewedPostprint (author's final draft
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