Treatment of Ankylosing Spondylitis Patients with Cervical Spinal Injury with Anterior Single-Stage Fixation with Bone Cement Augmentation.

Background/Objectives: Cervical spine fractures in ankylosing spondylitis (AS) are characterized as highly unstable fractures posing an elevated risk of neurological deficit and a significantly elevated mortality rate. This study assesses the efficacy and safety of single-stage plate stabilization with ventral cement augmentation in treating subaxial cervical spine fractures in patients with AS. Methods: Over 86 months, 38 patients diagnosed with AS received ventral plate stabilization with cement augmentation after suffering unstable subaxial cervical fractures. No additional dorsal stabilization was used in any of these surgeries. Results: There were no complications as a result of cement leakage. During the follow-up period, screw loosening and implant displacement were documented in two out of 38 cases. At the time of data analysis, 17 patients who had undergone treatment had died, representing 44.7% of the total cases. Seven patients died within 1 month, two patients died within 6 months, four patients died within 1 year, and four patients died after 1 year. Conclusions: Our study shows that a single-stage anterior screw and plate fixation of the cervical spine with cement augmentation could be a feasible and effective method to treat cervical spine fractures in patients with AS.

Tryptophanhydroxamic Acid-Stabilized Ultrasmall Gold Nanoclusters: Tuning the Selectivity for Metal Ion Sensing.

Sub-nanometer-sized gold nanoclusters (Au NCs) were prepared via the spontaneous reduction of [AuCl4]-- ions with a hydroxamate derivative of L-tryptophan (Trp) natural amino acid (TrpHA). The prepared TrpHA-Au NCs possess intense blue emission (λem = 470 nm; λex = 380 nm) with a 2.13% absolute quantum yield and 1.47 ns average lifetime. The Trp-stabilized noble metal NCs are excellent metal ion sensors for Fe3+, but in this work, we highlighted that the incorporation of the hydroxamate functional group with an excellent metal ion binding capability can tune the selectivity and sensitivity of these NCs, which is a promising way to design novel strategies for the detection of other metal ions as well. Moreover, their simultaneous identification can also be realized. By decreasing the sensitivity of our nano-sensor for Fe3+ (limit of detection (LOD) ~11 µM), it was clearly demonstrated that the selectivity for Cu2+-ions can be significantly increased (LOD = 3.16 µM) in an acidic (pH = 3-4) condition. The surface-bounded TrpHA molecules can coordinate the Cu2+ confirmed by thermodynamic data, which strongly generates the linking of the NCs via the Cu2+ ions in acidic pH, and a parallel fluorescence quenching occurs. In the case of Fe3+, the degree of quenching strongly depends on the metal ion concentration, and it only occurs when the NCs are not able to bind more Fe3+ (~10 µM) on the surface, causing the NCs' aggregation.

Thermodynamic Characterization of the Interaction of Biofunctionalized Gold Nanoclusters with Serum Albumin Using Two- and Three-Dimensional Methods.

Fluorescent gold nanoclusters have been successfully used as fluorescent markers for imaging of cells and tissues, and their potential role in drug delivery monitoring is coming to the fore. In addition, the development of biosensors using structure-tunable fluorescent nanoclusters is also a prominent research field. In the case of these sensor applications, the typical goal is the selective identification of, e.g., metal ions, small molecules having neuroactive or antioxidant effects, or proteins. During these application-oriented developments, in general, there is not enough time to systematically examine the interaction between nanoclusters and relevant biomolecules/proteins from a thermodynamic viewpoint. In this way, the primary motivation of this article is to carry out a series of tests to partially fill this scientific gap. Besides the well-known fluorescent probes, the mentioned interactions were investigated using such unique measurement methods as surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC). These two-dimensional (at the solid/liquid interface) and three-dimensional (in the bulk phase) measuring techniques provide a unique opportunity for the thermodynamic characterization of the interaction between different gold nanoclusters containing various surface functionalizing ligands and bovine serum albumin (BSA).

Lipid-Based Nanocarriers for Delivery of Neuroprotective Kynurenic Acid: Preparation, Characterization, and BBB Transport.

Encapsulation possibilities of an extensively investigated neuroprotective drug (kynurenic acid, KYNA) are studied via lipid-based nanocarriers to increase the blood-brain barrier (BBB) specific permeability. The outcomes of various preparation conditions such as stirring and sonication time, concentration of the lipid carriers and the drug, and the drug-to-lipid ratio are examined. Considering the experimentally determined encapsulation efficiency, hydrodynamic diameter, and ζ-potential values, the initial lipid and drug concentration as well as the stirring and sonication time of the preparation were optimized. The average hydrodynamic diameter of the prepared asolectin-(LIP) and water-soluble lipopolymer (WSLP)-based liposomes was found to be ca. 25 and 60 nm under physiological conditions. The physicochemical characterization of the colloidal carriers proves that the preparation of the drug-loaded liposomes was a successful process, and secondary interactions were indicated between the drug molecule and the polymer residues around the WSLP membrane. Dissolution profiles of the active molecule under physiological conditions were registered, and the release of the unformulated and encapsulated drug is very similar. In addition to this outcome, the in vitro polar brain lipid extract (porcine)-based permeability test proved the achievement of two- or fourfold higher BBB specific penetration and lipid membrane retention for KYNA in the liposomal carriers relative to the unformatted drug.

The Effect of Concentration, Temperature, and pH on the Formation of Hyaluronic Acid-Surfactant Nanohydrogels.

The assembly of colloidal hyaluronic acid (HyA, as a polysaccharide) based hydrogel particles in an aqueous medium is characterized in the present paper, with an emphasis on the particular case of nanohydrogels formed by surfactant-neutralized polysaccharide networks. The structural changes and particle formation process of polysaccharide- and cationic-surfactant-containing systems were induced by the charge neutralization ability and the hydrophobic interactions of cetyltrimethylammonium bromide (CTAB) under different conditions. Based on the rheological, light scattering, ζ-potential, turbidity, and charge titration measurements, it can be concluded that the preparation of the HyA-CTAB particles can be greatly controlled. The results indicate that more available negative charges can be detected on the polymer chain at smaller initial amounts of HyA (cHyA < 0.10 mg/mL), where a molecular solution can be formed. The change in the pH has a negligible effect on the formation process (particle aggregation appears at nCTAB/nHyA,monomer~1.0 in every case), while the temperature dependence of the critical micelle concentration (c.m.c.) of CTAB determines the complete neutralization of the forming nanohydrogels. The results of our measurements confirm that after the appearance of stable colloidal particles, a structural change and aggregation of the polymer particles take place, and finally the complete charge neutralization of the system occurs.

Impact of COVID-19 on neurotrauma cases, mortality rates, and rebound effect: a monocenter retrospective study.

Background and purpose:

We retro­spec­tively studied the development of neuro­trauma case numbers during the COVID-19 pandemic in the largest trauma center in Hun­gary and compared them to the data of the previous year. We hypothesized that the decrease in the number of neurotrauma cases during the restrictions would sub­sequently lead to a significant increase in a so-called rebound phenomenon. Our goal was to better understand the effect of the pandemic and the restrictive measures on neurotrauma admissions to help better pre­pare for a new pandemic or for other mobility restrictions. 

We compiled daily case numbers from January 1, 2019, to April 30, 2021, which included the treatment of 861 patients with spinal trauma and 1244 patients with head injuries from 2019 to 2020, and 871 and 1255 patients with spinal trauma and head injuries, respectively, from March 2020 to April 30, 2021. The parameters studied were patients’ age, admission date and time from injury to admission. We also conducted a minimum 3-month follow-up study with pa­tients admitted during the pandemic to determine the changes in the hazard ratio of mortality. 

We found that in each wave of the pandemic, during the restrictive measures, neurotrauma case numbers decreased. After the first restrictions, we observed a clinically relevant rebound effect among spinal trauma patients. The main findings of the follow-up were that the hazard ratio of mortality for COVID-19 infected patients was 2.5 (p < 0.001), compared with the mortality hazard ratio of COVID-19-negative patients.

Restrictions during the pandemic significantly reduced population mobility helping slow down the spread of the virus and give time to healthcare systems to better prepare. At the same time, it also reduced the number of new neurotrauma cases. In case of spinal trauma patients, a rebound effect was observed after the restrictions, which may be due to increased mobility, activity and travel. The restrictive measures reduced trauma cases effectively, while not increased the time from injury to admission. 

Core-Shell Structured PLGA Particles Having Highly Controllable Ketoprofen Drug Release.

The non-steroid anti-inflammatory drug ketoprofen (KP) as a model molecule is encapsulated in different poly(lactide-co-glycolide) (PLGA) nanostructured particles, using Tween20 (TWEEN) and Pluronic F127 (PLUR) as stabilizers to demonstrate the design of a biocompatible colloidal carrier particles with highly controllable drug release feature. Based on TEM images the formation of well-defined core-shell structure is highly favorable using nanoprecipitation method. Stabile polymer-based colloids with ~200-210 nm hydrodynamic diameter can be formed by successful optimization of the KP concentration with the right choice of stabilizer. Encapsulation efficiency (EE%) of 14-18% can be achieved. We clearly confirmed that the molecular weight of the stabilizer thus its structure greatly controls the drug release from the PLGA carrier particles. It can be determined that ~20% and ~70% retention is available with the use of PLUR and TWEEN, respectively. This measurable difference can be explained by the fact that the non-ionic PLUR polymer provides a steric stabilization of the carrier particles in the form of a loose shell, while the adsorption of the non-ionic biocompatible TWEEN surfactant results in a more compact and well-ordered shell around the PLGA particles. In addition, the release property can be further tuned by decreasing the hydrophilicity of PLGA by changing the monomer ratio in the range of ~20-60% (PLUR) and 70-90% (TWEEN).

Promising Bioactivity of Vitamin B1-Au Nanocluster: Structure, Enhanced Antioxidant Behavior, and Serum Protein Interaction.

In the current work, we first present a simple synthesis method for the preparation of novel Vitamin-B1-stabilized few-atomic gold nanoclusters with few atomic layers. The formed nanostructure contains ca. eight Au atoms and shows intensive blue emissions at 450 nm. The absolute quantum yield is 3%. The average lifetime is in the nanosecond range and three main components are separated and assigned to the metal-metal and ligand-metal charge transfers. Based on the structural characterization, the formed clusters contain Au in zero oxidation state, and Vitamin B1 stabilizes the metal cores via the coordination of pyrimidine-N. The antioxidant property of the Au nanoclusters is more prominent than that of the pure Vitamin B1, which is confirmed by two different colorimetric assays. For the investigation into their potential bioactivity, interactions with bovine serum albumin were carried out and quantified. The determined stoichiometry indicates a self-catalyzed binding, which is almost the same value based on the fluorometric and calorimetric measurements. The calculated thermodynamic parameters verify the spontaneous bond of the clusters along the protein chain by hydrogen bonds and electrostatic interactions.

Flow-driven synthesis of calcium phosphate-calcium alginate hybrid chemical gardens.

Systems far-from-equilibrium self-assemble into spatiotemporal structures. Here, we report on the formation of calcium alginate gardens along with their inorganic hybrids when a sodium alginate solution containing sodium phosphate in various compositions is injected into a calcium chloride reservoir. The viscoelastic properties of the membranes developed are controlled by the injection rate, while their thickness by the amount of sodium phosphate besides diffusion. Inorganic hybrid membranes with constant thickness are synthesized in the presence of a sufficient amount of sodium phosphate. The electrochemical characterization of the membranes suggests that the driving force is the pH-gradient developing along the two sides; hence, the cell potential can be controlled by the addition of alkaline sodium phosphate into the sodium alginate solution.

Increased blood-brain barrier permeability of neuroprotective drug by colloidal serum albumin carriers.

Encapsulation possibilities of two neuroprotective drugs of slightly different structures, kynurenic acid (KYNA) and its more hydrophilic analogue (SzR72), are studied in bovine serum albumin (BSA) nanoparticles (NPs) to increase their permeability through the blood-brain barrier (BBB). The effect of various preparation conditions such as protein concentration, protein-to-drug ratio, pH, ionic strength, type, and amount of desolvation agent and cross-linker concentration are discussed. It was found that the encapsulation proved to be successful only if the drugs are added to the pre-prepared BSA NPs. If the pH of the medium is adjusted to 4.0 instead of 7.4 the drug loading increased (from 4.5 % to 20.7 % for KYNA) due to the electrostatic interaction between the oppositely charged functional groups accompanied by significant secondary structural changes verified by circular dichroism spectroscopy (CD) suggesting the drug insertion in the hydrophobic pockets of BSA. The in vitro polar brain lipid extract (porcine) based permeability test proved the aimed three-, or fourfold higher BBB specific penetration for KYNA in the carrier relative to the unformatted drug.

Evaluation of noble metal nanostructure-serum albumin interactions in 2D and 3D systems: Thermodynamics and possible mechanisms.

In this review, we clearly highlight the importance of the detailed study of the interactions between noble metal colloids (nanoparticles (NPs) and nanoclusters (NCs)) with serum albumins (SAs) due to their rapidly growing presence in biomedical research. Besides the changes in the structure and optical property of SA, we demonstrate that the characteristic localized surface plasmon resonance (LSPR) feature of the colloidal noble metal NPs and the size- and structure-dependent photoluminescence (PL) property of the sub-nanometer sized NCs are also altered differently because of the interactions between them. Namely, for plasmonic NPs - SA interactions the PL quenching of SA (mainly static) is identified, while the SA cause PL enhancement of the ultra-small NCs after complexation. This review summarizes that the thermodynamic nature and the possible mechanisms of the binding processes are dependent partly on the size, morphology, and type of the noble metals, while the chemical structure as well as the charge of the stabilizing ligands have the most dominant effect on the change in optical features. In addition to the thermodynamic data and proposed binding mechanisms provided by three-dimensional spectroscopic techniques, the quantitative and real-time data of "quasi" two-dimensional sensor apparatus should also be considered to provide a comprehensive evaluation on many aspects of the particle/cluster - SA interactions.

Detailed Calorimetric Analysis of Mixed Micelle Formation from Aqueous Binary Surfactants for Design of Nanoscale Drug Carriers.

While numerous papers have been published according to the binary surfactant mixtures, only a few articles provide deeper information on the composition dependence of the micellization, and even less work attempts to apply the enhanced feature of the mixed micelles. The most important parameter of the self-assembled surfactants is the critical micelle concentration (cmc), which quantifies the tendency to associate, and provides the Gibbs energy of micellization. Several techniques are known for determining the cmc, but the isothermal titration calorimetry (ITC) can be used to measure both cmc and enthalpy change (ΔmicH) accompanying micelle formation. Outcomes of our calorimetric investigations were evaluated using a self-developed routine for handling ITC data and the thermodynamic parameters of mixed micelle formation were obtained from the nonlinear modelling of temperature- and composition- dependent enthalpograms. In the investigated temperature and micelle mole fractions interval, we observed some intervals where the cmc is lower than the ideal mixing model predicted value. These equimolar binary surfactant mixtures showed higher solubilization ability for poorly water-soluble model drugs than their individual compounds. Thus, the rapid and fairly accurate calorimetric analysis of mixed micelles can lead to the successful design of a nanoscale drug carrier.

The pH-Dependent Controlled Release of Encapsulated Vitamin B1 from Liposomal Nanocarrier.

In this work, we firstly presented a simple encapsulation method to prepare thiamine hydrochloride (vitamin B1)-loaded asolectin-based liposomes with average hydrodynamic diameter of ca. 225 and 245 nm under physiological and acidic conditions, respectively. In addition to the optimization of the sonication and magnetic stirring times used for size regulation, the effect of the concentrations of both asolectin carrier and initial vitamin B1 on the entrapment efficiency (EE %) was also investigated. Thermoanalytical measurements clearly demonstrated that after the successful encapsulation, only weak interactions were discovered between the carriers and the drug molecules. Moreover, the dissolution profiles under physiological (pH = 7.40) and gastric conditions (pH = 1.50) were also registered and the release profiles of our liposomal B1 system were compared with the dissolution profile of the pure drug solution and a manufactured tablet containing thiamin hydrochloride as active ingredient. The release curves were evaluated by nonlinear fitting of six different kinetic models. The best goodness of fit, where the correlation coefficients in the case of all three systems were larger than 0.98, was reached by application of the well-known second-order kinetic model. Based on the evaluation, it was estimated that our liposomal nanocarrier system shows 4.5-fold and 1.5-fold larger drug retention compared to the unpackaged vitamin B1 under physiological conditions and in artificial gastric juice, respectively.

Serum protein-hyaluronic acid complex nanocarriers: Structural characterisation and encapsulation possibilities.

A protein-polysaccharide-based potential nanocarrier system have been developed via a simple, one-step preparation protocol without the use of long-term heating and the utilization of hardly removable crosslinking agents, surfactants, and toxic organic solvents. To the best of our knowledge, this article is the first which summarizes in detail the pH-dependent quantitative relationship between the bovine serum albumin (BSA) and hyaluronic acid (HyA) confirmed by several physico-chemical techniques. The formation of colloidal complex nanoconjugates with average diameter of ca. 210-240 nm is strongly depend on the pH and the applied BSA:HyA mass ratio. Particle charge titrations studies strongly support the core-shell type structure, where the BSA core is covered by a thick HyA shell. Besides the optimization of these conditions, the drug encapsulation capacity and the dissolution profiles have been also studied for ibuprofen (IBU) and 2-picolinic acid (2-PA) as model drugs.

Preparation of novel tissue acidosis-responsive chitosan drug nanoparticles: Characterization and in vitro release properties of Ca2+ channel blocker nimodipine drug molecules.

The pH-responsive intelligent drug release facility of hydrophobically modified chitosan nanoparticles (Chit NPs) (d = 5.2 ±â€¯1.1 nm) was presented in the case of poorly water soluble Ca2+ channel blocker nimodipine (NIMO) drug molecules. The adequate pH-sensitivity, i.e. the suitable drug carrier properties of the initial hydrophilic Chit were achieved by reductive amination of Chit with hexanal (C6-) and dodecanal (C12-) aldehydes. The successful modifications of the macromolecule were evidenced via FTIR measurements: the band appearing at 1412 cm-1 (CN stretching in aliphatic amines) in the cases of the hydrophobically modified Chit samples shows that the CN bond successfully formed between the Chit and the aldehydes. Hydrophobization of the polymer unambiguously led to lower water contents with lower intermolecular interactions in the prepared hydrogel matrix: the initial hydrophilic Chit has the highest water content (78.6 wt%) and the increasing hydrophobicity of the polymer resulted in decreasing water content (C6-chit.: 74.2 wt% and C12-chit.: 47.1 wt%). Furthermore, it was established that the length of the side chain of the aldehyde influences the pH-dependent solubility properties of the Chit. Transparent homogenous polymer solution was obtained at lower pH, while at higher pH the formation of polymer (nano)particles was determined and the corresponding cut-off pH values showed decreasing tendency with increasing hydrophobic feature (pH = 7.47, 6.73 and 2.49 for initial Chit, C6-chit and C12-chit, respectively). Next the poorly water soluble NIMO drug was encapsulated with the C6-chit with adequate pH-sensitive properties. The polymer-stabilized NIMO particles with 10 wt% NIMO content resulted in stable dispersion in aqueous phase, the formation of polymer shell increased in the water solubility/dispersibility of the initial hydrophobic drug. According to the drug release experiments, we clearly confirmed that the encapsulated low crystallinity NIMO drug remained closed in the polymer NPs at normal tissue pH (pH = 7.4, PBS buffer, physiological condition) but at pH < 6.5 which is typical for seriously ischemic brain tissue, 93.6% of the available 0.14 mg/ml NIMO was released into the buffer solution under 8 h release time. According to this in vitro study, the presented pH-sensitive drug carrier system could be useful to selectively target ischemic brain regions characterized by acidosis, to achieve neuroprotection at tissue zones at risk of injury, without any undesirable side effects caused by systemic drug administration.

Cross-linked and hydrophobized hyaluronic acid-based controlled drug release systems.

This work demonstrates the preparation, structural characterization, and the kinetics of the drug release of hyaluronic acid (HyA)-based colloidal drug delivery systems which contain hydrophobic ketoprofen (KP) as model molecule. Because of the highly hydrophilic character of HyA the cross-linked derivatives at different cross-linking ratio have been synthesized. The hydrophobized variants of HyA have also been produced by modifying the polymer chains with cetyltrimethylammonium bromide (CTAB) at various HyA/CTAB ratios. Due to modifications the coherent structure of HyA changes into an incoherent colloidal system that were verified by rheological investigations. Nearly 70% of the encapsulated KP dissolve from the totally cross-linked HyA carrier but the release rate of KP is about 20% (after 8 h) from the CTAB-modified colloidal system at HyA monomer/CTAB 1:0.8 mass ratio. It has been verified that the modified HyA may be a potential candidate for controlled drug release of hydrophobic KP molecules.

Nucleotide-directed syntheses of gold nanohybrid systems with structure-dependent optical features: Selective fluorescence sensing of Fe3+ ions.

This study demonstrates a one-step synthesis for the preparation of both adenosine monophosphate (AMP)-stabilized colloidal gold nanoparticles (AMP-Au NPs) and fluorescent gold nanoclusters (AMP-Au NCs). The dominant role of AMP:AuCl4- molar ratios in the formation of diverse nanosized Au products was proved. The size, the structure and the unique structure-dependent optical properties of the NPs and NCs were determined based on the results of numerous spectroscopic (UV-vis, fluorescence, infrared, x-ray photoelectron), high resolution electron microscopy (HRTEM) and dynamic light scattering (DLS) techniques. Stabile AMP-Au NPs with diameter of ca. 11nm and ultra-small AMP-Au NCs having blue fluorescence (λem=480nm) were identified. In addition, the AMP-Au NCs have been utilized to develop a selective sensor for the detection of Fe3+ ions in aqueous medium based on fluorescence quenching. Several essential metal ions and anions have been tested but our results clearly supported that dominant quenching was observed only for Fe3+ ions. Based on the determined limit of detection (LOD=2.0µM) our system is capable of detecting Fe3+ ions in drinking water. The Stern-Volmer constants (KSV) and various thermodynamic parameters (ΔG, ΔH°, ΔS°, ΔCp) of the quenching process have also been determined by the Stern-Volmer fitting of the fluorescence data in order to better understand the quenching mechanism.

Kinetic and Thermodynamic Evaluation of Kynurenic Acid Binding to GluR1270-300 Polypeptide by Surface Plasmon Resonance Experiments.

This work clearly demonstrates an evaluation process that is easily performed and is simply based on the fitting of temperature-dependent surface plasmon resonance (SPR) sensorgrams to provide detailed thermodynamic characterization of biologically relevant interactions. The reversible binding of kynurenic acid (KYNA) on human glutamate receptor (GluR1) polypeptide (GluR1270-300)-modified gold surface has been studied at various temperatures under physiological conditions by two-dimensional SPR experiments. The registered sensorgrams were fitted by using different kinetic models without application of any commercial software. Assuming that the association of GluR1270-300-KYNA complex is first order in both reactants, the association (ka) and dissociation (kd) constants as well as the equilibrium constants (KA) and the Gibbs free-energy change (ΔG°) were given at 10, 20, 30, and 40 °C. Moreover, the enthalpy (ΔH° = -27.91 kJ mol(-1)), entropy (ΔS° = -60.33 J mol(-1) K(-1)), and heat capacity changes (ΔCp = -1.28 kJ mol(-1) K(-1)) of the model receptor-ligand system were also calculated using a spreadsheet program. Negative values of ΔG° and ΔH° indicate the exothermic formation of a stable GluR1270-300-KYNA complex, because the |ΔH| > |TΔS| relation suggests an enthalpy-driven binding process. The negative ΔH° and ΔS° values strongly support the formation of a salt bridge between KYNA and the positively charged residues of the polypeptide (Arg, Lys) at pH 7.4, confirmed by molecular docking calculations as well.

Investigation of the antibacterial effects of silver-modified TiO2 and ZnO plasmonic photocatalysts embedded in polymer thin films.

Nanosilver-modified TiO2 and ZnO photocatalysts were studied against methicillin-resistant Staphylococcus aureus on the surface and against naturally occurring airborne microorganisms. The photocatalysts/polymer nanohybrid films were prepared by spray coating technique on the surface of glass plates and on the inner surface of the reactive light source. The photoreactive surfaces were activated with visible light emitting LED light at λ = 405 nm. The optical properties of the prepared photocatalyst/polymer nanohybrid films were characterized by diffuse reflectance measurements. The photocatalytic properties were verified with the degradation of ethanol by gas chromatography measurements. The destruction of the bacterial cell wall component was examined with transmission electron microscope. The antibacterial effect of the photocatalyst/polymer nanohybrid films was tested with different methods and with the associated standard ISO 27447:2009. With the photoreactive coatings, an extensive disinfectant film was developed and successfully prepared. The cell wall component of S. aureus was degraded after 1 h of illumination. The antibacterial effect of the nanohybrid films has been proven by measuring the decrease of the number of methicillin-resistant S. aureus on the surface and in the air as the function of illumination time. The photocatalyst/polymer nanohybrid films could inactivate 99.9 % of the investigated bacteria on different thin films after 2 h of illumination with visible light source. The reactive light source with the inner-coated photocatalyst could kill 96 % of naturally occurring airborne microorganisms after 48 h of visible light illumination in indoor air sample. The TEM results and the microbiological measurements were completed with toxicity tests carried out with Vibrio fischeri bioluminescence bacterium.