Introduction: Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by joint inflammation and destruction, leading to significant pain and disability. Adenosine deaminase (ADA) is identified as a biomarker for RA’s inflammatory process. This study aims to investigate the potential of flavonoids and phenolic acids to inhibit ADA activity (in silico) and evaluate their anti-inflammatory effects in a RA model (in vivo). Methods: The molecular docking study was conducted using YASARA Structure 19.12.14. software following the Auto Dock 4.2 protocol. A rat model with pristane-induced arthritis was used to test the anti-inflammatory effect of selected polyphenols. The consistency of the development of the rat model was evaluated through the following indicators artistic score, paw volume, and body weight. Quercetin was administered intragastrically at doses of 150 and 400 mg/kg over 15 days. The C-reactive protein (CRP) level in serum was measured with an automatic biochemical analyzer. Statistical analyses were performed using SPSS 29.0.2.0. Results: Molecular docking simulations showed flavonoids inhibited ADA activity with inhibition constants ranging from 0.012 mM to 0.190 mM. In the in vivo RA model, quercetin significantly reduced joint inflammation and serum CRP levels at a higher dose of 400 mg/kg. Conclusion: Quercetin shows promise as an anti-inflammatory agent for RA by targeting ADA, suggesting that flavonoid-rich plant extracts could enhance RA treatment.

This paper shows the use of membrane filters in adsorption of solution of tetracycline hydrochloride on graphene materials. The adsorption process was monitored at different wavelengths, different pH values at certain time intervals. The absorbances of the solutions were measured by UV-Vis spectrophotometry at two wavelengths (275 nm and 356 nm), and three pH values (pH 4, pH 7 and pH 10) every 90 minutes for 6 hours of monitoring, with constant stirring in an ultrasonic bath. The results showed decrease in absorbance at both wavelength and in all three pH values which proved the adsorption of tetracycline hydrochloride on GO and rGO. The largest decrease in absorbance was 98.1%. The most suitable pH value for adsorption was pH 4. This paper used a unique approach to filtration through membrane filters, which in the future could lead to the development of membrane filters based on graphene materials.