Skin represents the largest organ in the human body, functioning as a protective barrier against environmental factors while playing a critical role in thermoregulation. Acne vulgaris is recognized as the most common dermatological condition affecting adolescents, and if left untreated, it can result in lasting skin damage and associated psychosocial challenges. This study aims to develop innovative polymeric biomaterials that could effectively support the treatment of acne vulgaris. The synthesis of these biomaterials involves the use of polyethylene glycol 6000, sodium alginate, and the antioxidant protein glutathione (GHS) to create polymeric hydrogels. These hydrogels were generated via a UV-mediated crosslinking process. To enhance the functional properties of the hydrogels, zinc oxide microparticles (ZnO), synthesized through a wet precipitation method, were incorporated into the formulations. Characterization of the ZnO was performed using Fourier-Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), particle sizer analysis, and Scanning Electron Microscopy (SEM). Additionally, the bioactivity of the synthesized materials was evaluated through incubation in media simulating physiological body fluids. The cytotoxic effects of the biomaterials were assessed using an indirect test on mouse fibroblast (L929) cells, in accordance with ISO 10993-5 guidelines. The results of our research indicate that the developed biomaterials exhibit potential as a carrier for active substances, contributing positively to the treatment of acne vulgaris and potentially improving overall skin health.

• Klíčová slova
• acne vulgaris, active substance carrier, hydrogels, polyethylene glycol, sodium alginate, zinc oxide microparticles,
• MeSH
• acne vulgaris farmakoterapie   MeSH
• algináty chemie   MeSH
• biokompatibilní materiály chemie   farmakologie   MeSH
• buněčné linie MeSH
• fibroblasty účinky léků   metabolismus   MeSH
• glutathion * metabolismus   MeSH
• hydrogely * chemie   MeSH
• kůže * účinky léků   metabolismus   MeSH
• lidé MeSH
• myši MeSH
• nosiče léků chemie   MeSH
• oxid zinečnatý * chemie   farmakologie   MeSH
• regenerace účinky léků   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• algináty MeSH
• biokompatibilní materiály MeSH
• glutathion * MeSH
• hydrogely * MeSH
• nosiče léků MeSH
• oxid zinečnatý * MeSH

The tear fluids from three healthy individuals and three patients with diabetes mellitus were examined using atomic force microscopy-infrared spectroscopy (AFM-IR) and Fourier transform infrared spectroscopy (FTIR). The dried tear samples showed different surface morphologies: the control sample had a dense network of heart-shaped dendrites, while the diabetic sample had fern-shaped dendrites. By using the AFM-IR technique we identified spatial distribution of constituents, indicating how diabetes affects the structural characteristics of dried tears. FTIR showed that the dendritic structures gradually disappeared over time due to glucose-induced lysozyme damage. The tear fluid from diabetes mellitus patients has a higher concentration of glucose, which accelerates the breakdown of lysozyme and, as a result, the quick loss of the dendritic structure. Our study shows that analysis of dry tear fluid can be promising technique for the detection of glycated proteins that reveal long lasting hyperglycemia and diabetes mellitus.

• Klíčová slova
• Diabetes mellitus, Photothermal AFM-IR analysis, Tear fluid,
• MeSH
• biologické markery * MeSH
• diabetes mellitus * patologie   metabolismus   MeSH
• dospělí MeSH
• glukosa MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikroskopie atomárních sil * MeSH
• muramidasa metabolismus   analýza   MeSH
• slzy * chemie   metabolismus   MeSH
• spektroskopie infračervená s Fourierovou transformací metody   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biologické markery * MeSH
• glukosa MeSH
• muramidasa MeSH

Human nails have recently become a sample of interest for toxicological purposes. Multiple studies have proven the ability to detect various analytes within the keratin matrix of the nail. The analyte of interest in this study is fentanyl, a highly dangerous and abused drug in recent decades. In this proof-of-concept study, ATR-FTIR was combined with machine learning methods, which are effective in detecting and differentiating fentanyl in samples, to explore whether nail samples are distinguishable from individuals who have used fentanyl and those who have not. PLS-DA and SVM-DA prediction models were created for this study and had an overall accuracy rate of 84.8% and 81.4%, respectively. Notably, when classification was considered at the donor level-i.e., determining whether the donor of the nail sample was using fentanyl-all donors were correctly classified. These results show that ATR-FTIR spectroscopy in combination with machine learning can effectively differentiate donors who have used fentanyl and those who have not and that human nails are a viable sample matrix for toxicology.

• Klíčová slova
• ATR–FTIR, PLS-DA, SVM-DA, fentanyl, fingernails, machine learning, toenails,
• MeSH
• fentanyl * analýza   MeSH
• lidé MeSH
• nehty * chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací metody   MeSH
• strojové učení * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fentanyl * MeSH

A person's age estimation from biological evidence is a crucial aspect of forensic investigations, aiding in victim identification and criminal profiling. In this study, we present a novel approach of utilizing Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) spectroscopy to predict the age of donors based on nail samples. A diverse dataset comprising nails from donors spanning different age groups was analyzed using ATR FT-IR, with subsequent multivariate analysis techniques used for age prediction. The developed partial least squares regression (PLS-R) model demonstrated promising accuracy in age estimation, with a root mean square error of prediction (RMSEP) equal to 11.1 during external validation. Additionally, a partial least squares discriminant analysis (PLS-DA) classification model achieved high accuracy of 88% in classifying donors into younger and older age groups during external validation. This proof-of-concept study highlights the potential of ATR FT-IR spectroscopy as a non-destructive and efficient tool for age estimation in forensic investigations, offering a new approach to forensic analysis with practical implications.

• Klíčová slova
• ATR FT‐IR, PLS‐DA, PLS‐R, age, chemometrics, nails,
• MeSH
• diskriminační analýza MeSH
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• metoda nejmenších čtverců MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nehty * chemie   MeSH
• ověření koncepční studie MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• soudní vědy metody   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• stárnutí MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Free radical polymerization technique was used to formulate Poloxamer-188 based hydrogels for controlled delivery. A total of seven formulations were formulated with varying concentrations of polymer, monomer ad cross linker. In order to assess the structural properties of the formulated hydrogels, Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Scanning electron microscopy (SEM), and X-ray diffraction (XRD) were carried out. To assess the effect of pH on the release of the drug from the polymeric system, drug release studies were carried in pH 1.2 and 7.4 and it was found that release of the drug was significant in pH 7.4 as compared to that of pH 1.2 which confirmed the pH responsiveness of the system. Different kinetic models were also applied to the drug release to evaluate the mechanism of the drug release from the system. To determine the safety and biocompatibility of the system, toxicity study was also carried out for which healthy rabbits were selected and formulated hydrogels were orally administered to the rabbits. The results obtained suggested that the formulated poloxamer-188 hydrogels are biocompatible with biological system and have the potential to serve as controlled drug delivery vehicles.

• MeSH
• akrylové pryskyřice * chemie   MeSH
• diferenciální skenovací kalorimetrie MeSH
• difrakce rentgenového záření MeSH
• hydrogely * chemie   MeSH
• koncentrace vodíkových iontů MeSH
• králíci MeSH
• léky s prodlouženým účinkem chemie   farmakokinetika   MeSH
• mikroskopie elektronová rastrovací MeSH
• nosiče léků chemie   MeSH
• poloxamer * chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• systémy cílené aplikace léků MeSH
• termogravimetrie MeSH
• timolol * aplikace a dávkování   farmakokinetika   chemie   MeSH
• uvolňování léčiv MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• akrylové pryskyřice * MeSH
• carbopol 940 MeSH Prohlížeč
• hydrogely * MeSH
• léky s prodlouženým účinkem MeSH
• nosiče léků MeSH
• poloxamer * MeSH
• timolol * MeSH

Cannabis sativa L. is a plant belonging to the Cannabaceae family known primarily for its recreational use due to the psychoactive properties of Δ9-tetrahydrocannabinol (THC). Despite this, several compounds belonging to the category of phytocannabinoids have shown in recent years a number of potentially promising therapeutic effects that have increased the interest in the pharmaceutical field towards this plant. However, the content of these compounds is very variable and influenced by different factors, such as growing conditions and time of the year. An indication of the status and age of Cannabis samples is provided by the content of CBN, a minor phytocannabinoid and degradation product of other phytocannabinoids, including THC. In this research work an innovative, solid state analytical approach has been developed to observe and evaluate the variations in the content of two phytocannabinoids (CBN and CBD) in Cannabis-derived products over time. In order to simulate the ageing of the Cannabis samples, an artificially accelerated ageing procedure has been developed and optimised by using high temperatures. The analyses were carried out using an innovative ATR-FTIR method for solid state analysis, enabling direct analysis of a solid sample without any pretreatment phase. This study has allowed the development of an innovative analytical approach for the evaluation of the age and state of conservation of Cannabis samples and may be a useful tool both in the industrial, pharmaceutical and forensic fields.

• Klíčová slova
• ATR-FTIR, Accelerated ageing, Cannabis sativa L., Phytocannabinoids, Solid-state analysis,
• MeSH
• Cannabis * chemie   MeSH
• časové faktory MeSH
• kanabidiol analýza   chemie   MeSH
• kanabinoidy * analýza   chemie   MeSH
• rostlinné extrakty chemie   analýza   MeSH
• spektroskopie infračervená s Fourierovou transformací metody   MeSH
• stabilita léku MeSH
• tetrahydrokanabinol analýza   chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kanabidiol MeSH
• kanabinoidy * MeSH
• rostlinné extrakty MeSH
• tetrahydrokanabinol MeSH

The transformation of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipid bilayers from the gel (Lβ') to the fluid (Lα) phase involves an intermediate ripple (Pβ') phase forming a few degrees below the main transition temperature (Tm). While the exact cause of bilayer rippling is still debated, the presence of amphiphilic molecules, pH, and lipid bilayer architecture are all known to influence (pre)transition behavior. In particular, fatty acid chains interact with hydrophobic lipid tails, while the carboxylic groups simultaneously participate in proton transfer with interfacial water in the polar lipid region which is controlled by the pH of the surrounding aqueous medium. The molecular-level variations in the DPPC ripple phase in the presence of 2% palmitic acid (PA) were studied at pH levels 4.0, 7.3, and 9.1, where PA is fully protonated, partially protonated, or fully deprotonated. Bilayer thermotropic behavior was investigated by differential scanning calorimetry (DSC) and Fourier-transform infrared (FTIR) spectroscopy which agreed in their characterization of (pre)transition at pH of 9.1, but not at pH 4.0 and especially not at 7.3. Owing to the different insertion depths of protonated and deprotonated PA, along with the ability of protonated PA to undergo flip-flop in the bilayer, these two forms of PA show a different hydration pattern in the interfacial water layer. Finally, these results demonstrated the hitherto undiscovered potential of FTIR spectroscopy in the detection of the events occurring at the surface of lipid bilayers that obscure the low-cooperativity phase transition explored in this work.

• Klíčová slova
• 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipid bilayers, DSC and FTIR spectroscopy, Palmitic acid (PA), Ripple phase, pH-dependent (de)protonation,
• MeSH
• 1,2-dipalmitoylfosfatidylcholin * analogy a deriváty   MeSH
• diferenciální skenovací kalorimetrie MeSH
• koncentrace vodíkových iontů MeSH
• kyselina palmitová * chemie   MeSH
• lipidové dvojvrstvy * chemie   MeSH
• molekulární struktura MeSH
• protony MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• teplota MeSH
• změna skupenství MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 1,2-dipalmitoylfosfatidylcholin * MeSH
• colfosceril palmitate MeSH Prohlížeč
• kyselina palmitová * MeSH
• lipidové dvojvrstvy * MeSH
• protony MeSH

This paper, for the first time, presents a potential application of titanium(IV) oxide and silicon(IV) oxide combined with lignin through a solvent-free mechanical process as admixtures for cement composites. The designed TiO2-SiO2 (1:1 wt./wt.) hybrid materials mixed with lignin were extensively characterized using Fourier transform infrared spectroscopy (FTIR), electrokinetic potential analysis, thermal analysis (TGA/DTG), and porous structure properties. In addition, particle size distributions and scanning electron microscopy (SEM) were conducted to evaluate morphological and microstructural properties. In the next step, the effect of the TiO2-SiO2/lignin hybrid admixture on the workability, hydration process, microstructure, porosity, mechanical, and antimicrobial properties of the cement composites was evaluated. It was observed that appropriately designed hybrid systems based on lignin contributed to better workability, with an improvement of 25 mm, and reduced porosity of cement composites, decreasing from 14.4 % to 13.3 % in the most favorable sample. Additionally, a higher microstructure density was observed, and with increasing amounts of hybrid material admixture, the mechanical parameters also improved. In addition, the TiO2-SiO2/lignin hybrid systems had significant potential due to their high microbial purity, suggesting their effectiveness in minimizing microbial accumulation on surfaces. The final stage of analysis involved employing response surface methodology (RSM) to ascertain the optimum composition of cement composites. The results obtained indicate that the TiO2-SiO2/lignin admixtures are a promising approach for the valorization of lignin waste flows in the design of cement composites.

• Klíčová slova
• Cement composites, Hybrid materials, Lignin, TiO(2)–SiO(2) oxide system,
• MeSH
• antiinfekční látky chemie   farmakologie   MeSH
• konstrukční materiály MeSH
• lignin * chemie   MeSH
• oxid křemičitý chemie   MeSH
• poréznost MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• titan chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antiinfekční látky MeSH
• lignin * MeSH
• oxid křemičitý MeSH
• titan MeSH
• titanium dioxide MeSH Prohlížeč

It is essential to study the interactions between nanoparticles and proteins to better understand the biological interactions of nanoparticles. In this study, we studied the protein adsorption mode on the surface of Ag-doped TiO2 nanoparticles (NPs) using a model protein, bovine serum albumin (BSA). The mechanism of binding BSA to the Ag-doped TiO2 NPs was studied by applying fluorescence quenching, absorbance measurements, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy techniques. The strong binding between BSA and Ag-doped TiO2 NPs was confirmed by a high value of binding constant (K = 2.65 × 105 L mol-1). We also studied the thermal stability of BSA in the presence of the Ag-doped TiO2 NPs. Thermodynamic parameters indicated that the adsorption of BSA on the Ag-doped TiO2 NPs was a spontaneous, natural and exothermic process. The effect of Ag-doped TiO2 NPs on the transportation function of BSA was also studied using a fluorescence spectroscopic technique. Fluorescence spectroscopic data suggested the existence of a strong interaction between BSA and the surface of the Ag-doped TiO2 NPs, which indicated that the binding affinities of some selected amino acids in BSA changed. This, in turn, clearly confirms that the Ag-doped TiO2 NPs affect the transportation capability of BSA in blood.

• MeSH
• adsorpce MeSH
• cirkulární dichroismus MeSH
• fluorescenční spektrometrie MeSH
• kovové nanočástice chemie   MeSH
• nanočástice chemie   MeSH
• sérový albumin hovězí * chemie   MeSH
• skot MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• stříbro * chemie   MeSH
• termodynamika MeSH
• titan * chemie   MeSH
• vazba proteinů MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• sérový albumin hovězí * MeSH
• stříbro * MeSH
• titan * MeSH
• titanium dioxide MeSH Prohlížeč

Restoring the structures and functions of tissues along with organs in human bodies is a topic gathering attention nowadays. These issues are widely discussed in the context of regenerative medicine. Excipients/delivery systems play a key role in this topic, guaranteeing a positive impact on the effectiveness of the drugs or therapeutic substances supplied. Advances in materials engineering, particularly in the development of hydrogel biomaterials, have influenced the idea of creating an innovative material that could serve as a carrier for active substances while ensuring biocompatibility and meeting all the stringent requirements imposed on medical materials. This work presents the preparation of a natural polymeric material based on pullulan modified with silymarin, which belongs to the group of flavonoids and derives from a plant called Silybum marianum. Under UV light, matrices with a previously prepared composition were crosslinked. Before proceeding to the next stage of the research, the purity of the composition of the matrices was checked using Fourier-transform infrared (FT-IR) spectroscopy. Incubation tests lasting 19 days were carried out using incubation fluids such as simulated body fluid (SBF), Ringer's solution, and artificial saliva. Changes in pH, electrolytic conductivity, and weight were observed and then used to determine the sorption capacity. During incubation, SBF proved to be the most stable fluid, with a pH level of 7.6-7.8. Sorption tests showed a high sorption capacity of samples incubated in both Ringer's solution and artificial saliva (approximately 350%) and SBF (approximately 300%). After incubation, the surface morphology was analyzed using an optical microscope for samples demonstrating the greatest changes over time. The active substance, silymarin, was released using a water bath, and then the antioxidant capacity was determined using the Folin-Ciocâlteu test. The tests carried out proved that the material produced is active and harmless, which was shown by the incubation analysis. The continuous release of the active ingredient increases the biological value of the biomaterial. The material requires further research, including a more detailed assessment of its balance; however, it demonstrates promising potential for further experiments.

• Klíčová slova
• flavonoids, polyethylene glycol, polymers, pullulan, silymarin,
• MeSH
• glukany * chemie   MeSH
• koncentrace vodíkových iontů MeSH
• lidé MeSH
• nosiče léků * chemie   MeSH
• polyethylenglykoly * chemie   MeSH
• silymarin * chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• systémy cílené aplikace léků metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• glukany * MeSH
• nosiče léků * MeSH
• polyethylenglykoly * MeSH
• pullulan MeSH Prohlížeč
• silymarin * MeSH