Constantinos Voniatis

Dr. Constantinos Voniatis

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 March 2021 in Antimicrobial Resistance & Infection Control
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CVConstantinos Voniatis
Constantinos Voniatis
SBSzáva Bánsághi
Száva Bánsághi
AFAndrea Ferencz
Andrea Ferencz
Tamás HaideggerTamás Haidegger
Tamás Haidegger
Background: Current hand hygiene guidelines do not provide recommendations on a specific volume for the clinical hand rubbing procedure. According to recent studies volume should be adjusted in order to achieve complete coverage. However, hand size is a parameter that highly influences the hand coverage quality when using alcohol-based handrubs (ABHR). The purpose of this study was to establish a quantitative correlation between applied ABHR volume and achieved hand coverage. Method: ABHR based hand hygiene events were evaluated utilizing a digital health device, the Semmelweis hand hygiene system with respect to coverage achieved on the skin surface. Medical students and surgical residents (N = 356) were randomly selected and given predetermined ABHR volumes. Additionally, hand sizes were calculated using specialized software developed for this purpose. Drying time, ABHR volume awareness, as well spillage awareness were documented for each hand hygiene event. Results: Hand coverage achieved during a hand hygiene event strongly depends on the applied ABHR volume. At a 1 ml dose, the uncovered hand area was approximately 7.10%, at 2 ml it decreased to 1.68%, and at 3 ml it further decreased to 1.02%. The achieved coverage is strongly correlated to hand size, nevertheless, a 3 ml applied volume proved sufficient for most hand hygiene events (84%). When applying a lower amount of ABHR (1.5 ml), even people with smaller hands failed to cover their entire hand surface. Furthermore, a 3 ml volume requires more than the guideline prescribed 20–30 s to dry. In addition, results suggest that drying time is not only affected by hand size, but perhaps other factors may be involved as well (e.g., skin temperature and degree of hydration). ABHR volumes of 3.5 ml or more were inefficient, as the disinfectant spilled while the additional rubbing time did not improve hand coverage. Conclusions: Hand sizes differ a lot among HCWs. After objectively measuring participants, the surface of the smallest hand was just over half compared to the largest hand (259 cm2 and 498 cm2, respectively). While a 3 ml ABHR volume is reasonable for medium-size hands, the need for an optimized volume of handrub for each individual is critical, as it offers several advantages. Not only it can ensure adequate hand hygiene quality, but also prevent unnecessary costs. Bluntly increasing the volume also increases spillage and therefore waste of disinfectant in the case of smaller hands. In addition, adherence could potentially decrease due to the required longer drying time, therefore, adjusting the dosage according to hand size may also increase the overall hand hygiene compliance.

26 April 2022 in Nanomaterials
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TVTamás Veres
Tamás Veres
CVConstantinos Voniatis
Constantinos Voniatis
KMKristof Molnar
Kristof Molnar
DNDániel Nesztor
Dániel Nesztor
DFDaniella Fehér
Daniella Fehér
AJAngela Jedlovszky-Hajdu
Angela Jedlovszky-Hajdu
When exposed to an alternating magnetic field, superparamagnetic nanoparticles can elicit the required hyperthermic effect while also being excellent magnetic resonance imaging (MRI) contrast agents. Their main drawback is that they diffuse out of the area of interest in one or two days, thus preventing a continuous application during the typical several-cycle multi-week treatment. To solve this issue, our aim was to synthesise an implantable, biodegradable membrane infused with magnetite that enabled long-term treatment while having adequate MRI contrast and hyperthermic capabilities. To immobilise the nanoparticles inside the scaffold, they were synthesised inside hydrogel fibres. First, polysuccinimide (PSI) fibres were produced by electrospinning and crosslinked, and then, magnetitc iron oxide nanoparticles (MIONs) were synthesised inside and in-between the fibres of the hydrogel membranes with the well-known co-precipitation method. The attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) investigation proved the success of the chemical synthesis and the presence of iron oxide, and the superconducting quantum interference device (SQUID) study revealed their superparamagnetic property. The magnetic hyperthermia efficiency of the samples was significant. The given alternating current (AC) magnetic field could induce a temperature rise of 5 °C (from 37 °C to 42 °C) in less than 2 min even for five quick heat-cool cycles or for five consecutive days without considerable heat generation loss in the samples. Short-term (1 day and 7 day) biocompatibility, biodegradability and MRI contrast capability were investigated in vivo on Wistar rats. The results showed excellent MRI contrast and minimal acute inflammation.

22 November 2021 in Journal of Applied Polymer Science
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CVConstantinos Voniatis
Constantinos Voniatis
RGRamóna Gottscháll
Ramóna Gottscháll
DBDóra Barczikai
Dóra Barczikai
GSGyörgy Szabó
György Szabó
AJAngela Jedlovszky-Hajdu
Angela Jedlovszky-Hajdu
The following manuscript presents a comprehensive investigation regarding the influence of electrospinning parameters on fiber quality and mechanical properties of nanofibrous poly(amino acid) meshes. At first, we examine parameters including: solvent options, polymer concentrations, collector speed and distance, voltage, needle sizes and flow rates to prepare fibrous scaffolds based on polysuccinimide. The main objective was to attempt and decrease the fiber diameter as much as possible while not reducing the fiber quality. After that mechanical properties of the meshes were investigated, we demonstrate two possible methods to reinforce them: mechanically induced alignment of the fibers and multilayer compression. Characterization methods include a solubility study, viscosity and conductivity measurements, ATR‐FTIR spectroscopy, scanning electron microscopy, and mechanical uniaxial test. Fiber size was successfully reduced from 615 to 280 nm without any quality aberrations. Mechanical performance not only improved almost three‐fold, but was also enhanced in two directions due to the multilayer composition. With these optimizations, the PSI mesh now possess favorable features for biomedical application according to the relevant literature.

16 January 2023 in Membranes
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CVConstantinos Voniatis
Constantinos Voniatis
OZOlivér Závoti
Olivér Závoti
KMKenigen Manikion
Kenigen Manikion
BBBálint Budavári
Bálint Budavári
AHAngela Jedlovszky Hajdu
Angela Jedlovszky Hajdu
Poly(vinyl-alcohol) hydrogels have already been successfully utilised as drug carrier systems and tissue engineering scaffolds. However, lacking mechanical strength and suturability hinders any prospects for clinical and surgical applications. The objective of this work was to fabricate mechanically robust PVA membranes, which could also withstand surgical manipulation and suturing. Electrospun membranes and control hydrogels were produced with 61 kDa PVA. Using a high-speed rotating cylindrical collector, we achieved fibre alignment (fibre diameter: 300 ± 50 nm). Subsequently, we created multilayered samples with different orientations to achieve multidirectional reinforcement. Finally, utilising glutaraldehyde as a cross-linker, we created insoluble fibrous-hydrogel membranes. Mechanical studies were performed, confirming a fourfold increase in the specific loading capacities (from 0.21 to 0.84 Nm2/g) in the case of the monolayer samples. The multilayered membranes exhibited increased resistance from both horizontal and vertical directions, which varies according to the specific arrangement. Finally, the cross-linked fibrous hydrogel samples not only exhibited specific loading capacities significantly higher than their counterpart bulk hydrogels but successfully withstood suturing. Although cross-linking optimisation and animal experiments are required, these membranes have great prospects as alternatives to current surgical meshes, while the methodology could also be applied in other systems as well.

22 September 2023 in Journal of Molecular Liquids
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CVConstantinos Voniatis
Constantinos Voniatis
KMKenigen Manikion
Kenigen Manikion
GGGergő Gyulai
Gergő Gyulai
AJAngela Jedlovszky-Hajdu
Angela Jedlovszky-Hajdu

28 April 2026 in Pharmaceutics
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CCChristodoulos Chrysanthou
Christodoulos Chrysanthou
KMKenigen Manikion
Kenigen Manikion
CVConstantinos Voniatis
Constantinos Voniatis
Postoperative pain management (POPM) remains a major clinical challenge despite its vital importance in reducing surgical stress, enabling early mobilization, and limiting postoperative complications. Conventional analgesic strategies are often constrained by short drug half-lives, repeated dosing requirements, systemic adverse effects, and the risk of opioid-related toxicity or dependence. These limitations suggest that the mode of drug delivery, in addition to drug selection itself, is a critical determinant of therapeutic performance. In this context, electrospun fibrous meshes represent a promising platform for localized and sustained analgesic delivery. Their high surface-area-to-volume ratio, tuneable porosity, broad polymer compatibility, and capacity to incorporate single or multiple bioactive agents make them attractive candidates for postoperative applications. This review summarizes recent advances in electrospun meshes for POPM, with particular emphasis on fabrication strategies, polymer selection, drug incorporation approaches, drug-release behaviour, biological performance, and translational challenges.