Gábor Katona

Background/Objectives: Chlamydia trachomatis (C. trachomatis) infections represent a major global public health concern, with over 100 million new cases annually. Although commonly used antibiotics like azithromycin and doxycycline are generally effective, increasing antibiotic resistance and therapeutic failures highlight the need for alternative treatments and innovative delivery systems. Methods: The efficacy of alternative antimicrobial agents, including ciprofloxacin and the combination of sulfamethoxazole and trimethoprim, was evaluated in both free and nano-formulated states. Drug encapsulation was achieved using liposomes as well as niosomal and aspasomal delivery systems. In vitro experiments were conducted on HeLa cells infected with C. trachomatis serovar D. Host cell viability and cytotoxicity were assessed using the MTT assay, while bacterial genomic load was quantified by qPCR. Results: Encapsulation significantly enhanced antimicrobial activity, with certain antibiotic-loaded lipid nanoparticles demonstrating 2–4 times greater effectiveness compared to their free counterparts. The prepared formulations exhibited no cytotoxic effects and did not interfere with PCR-based detection, confirming that observed outcomes reflect true antimicrobial activity. Conclusions: Nanocarrier-based drug delivery, particularly using lipid nanoparticles, represents a promising strategy for improving the therapeutic management of C. trachomatis infections. These findings highlight the potential of delivery platforms to enhance antibiotic performance and support the development of more effective and innovative antimicrobial therapies.

Periodontitis is a chronic inflammatory disease marked by the progressive destruction of periodontal tissues, where conventional therapies often fail to maintain adequate drug levels at the target site. This study reports the development and characterization of a thermosensitive gel containing nanostructured lipid carriers (NLC) for controlled local periodontal delivery. Apigenin (AP)-loaded NLC were prepared using AP as active agent and clove essential oil (CEO) as liquid lipid subsequently incorporated into Poloxamer 407 (5–15% w/w) hydrogels. The formulations were evaluated in relation to particle size, morphology, thermal and rheological behavior, mucoadhesion, in vitro release, antibacterial activity, and stability. Optimized nanoscale NLC showed a high entrapment efficiency, and uniform morphology. Raman analysis confirmed successful AP incorporation and homogeneous distribution in the gel without incompatibility. NLC-loaded gels exhibited sol–gel transition at physiological temperature with improved viscoelasticity and enhanced mucoadhesion. The drug release was sustained for 48 h and followed the Korsmeyer–Peppas model, indicating diffusion-based and anomalous transport. The antibacterial assessment demonstrated the pronounced inhibitory activity of the NLC formulations against key periodontal pathogens, with the formulation-dependent modulation of antimicrobial efficacy observed following the gel incorporation. Stability studies showed preserved nanoparticle structure and uniform dispersion. Overall, the thermoresponsive NLC-hydrogel system offers a promising strategy for prolonged, localized periodontal therapy.

Background/Objectives: Poor aqueous solubility and limited nasal permeability remain key challenges in the intranasal delivery of carbamazepine. In this study, biocompatible bovine serum albumin nanoparticles functionalized with sulfobutyl-β-cyclodextrin (SβCD-BSA NPs), comprising individually cytocompatible components with confirmed physical interactions), were formulated for intranasal delivery of carbamazepine (CBZ). Methods: The ethanolic desolvation method was utilised for the preparation of the nanoparticles, with the functional moiety incorporated during nanoparticle preparation. The effects of different molar ratios of SβCD-BSA and different ethanol volume ratios were studied. For crosslinking, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), a non-toxic crosslinker, was utilised. To determine the role of the SβCD, two preparation samples were formulated, with and without SβCD. Results: The formulation without SβCD incorporation had a mean particle size of 125 ± 0.64 nm, polydispersity index (PDI) of 0.34, encapsulation efficiency (EE%) of 61.5 ± 1.40%, and drug-loading ratio (DL%) of 31.9 ± 1.50%. Conversely, the SβCD-functionalized formulation showed a mean particle size of 128 ± 2.12 nm, PDI of 0.21 ± 0.03, EE of 64.6 ± 0.35%, and DL of 34.28 ± 1.60%. Statistical analysis revealed that the incorporation of SβCD resulted in a statistically significant increase in both DL% and EE% (p < 0.05). Conversely, the observed differences in particle size and PDI were not statistically significant (p > 0.05). This addition provides precise context regarding the comparability of the formulations while highlighting SβCD’s functional benefits in solubility and permeation. The interaction between CBZ and SβCD-BSA was confirmed using Fourier-transform infrared spectroscopy. Lastly, the prepared formulations were characterised by their physicochemical attributes and in vitro biopharmaceutical studies. It was discovered that SβCD plays a dual role, enhancing the solubility of CBZ in one scenario while promoting its nasal permeation, suggesting its potential use in epilepsy treatment. Conclusions: These findings highlight the potential of SβCD-BSA NPs as a versatile pharmaceutics platform for the intranasal delivery of poorly soluble CNS drugs.

Background: The oral delivery of biopharmaceuticals remains a major challenge for researchers and the pharmaceutical industry. Therefore, extensive research is ongoing to develop a viable delivery method, hence self-emulsifying drug delivery systems (SEDDSs) are being investigated because of their ability to protect the carried macromolecules in the gastrointestinal environment and facilitate absorption through the intestinal barrier. Objectives: To systematically investigate this promising method for the oral delivery of lysozyme (LYZ) and to model oral peptide/protein administration. Methods: LYZ/sodium dodecyl sulfate (SDS) hydrophobic ion pairs (HIPs) were prepared to enhance protein solubility and stability in SEDDSs. Different surfactants (Tween^® 20 and 80) and as co-surfactants (Span^® 20 and 80) were combined for the preparation of liquid SEDDSs according to a 2² full factorial design and samples of each combination were formulated based on a three-factor-constrained mixture design. The critical quality attributes (CQAs), droplet size, polydispersity index (PDI), and zeta potential were measured by dynamic light scattering (DLS). The process design space was determined by response surface methodology (RSM) and two-dimensional ternary contour plots. An in vitro release test was performed using the sample-and-separate approach. Results: Emulsions of SEDDSs with the optimal properties of droplet size < 200 nm, PDI < 0.4 and zeta potential < −10 mV were prepared. Consequently, a HIP load of 10 mg/g was achievable, exhibiting apparent first-order kinetics, with approximately 80% of the loaded LYZ released within 6 h. Conclusions: This study may contribute to better understanding of the effects and interactions of formulating materials for SEDDSs and their possible role in the oral delivery of biopharmaceuticals.