Biology subjects

Rochev, Y.

Publications and source records attributed to Rochev, Y..

3 recordsLinked to original sources

bioRxiv2025

Optimisation and validation of a rapid RP-HPLC method for budesonide quantification from polymeric nanoparticles with application to stability and drug release studies

Robust and sustainable analytical tools are essential for the design, manufacture, and evaluation of advanced drug delivery systems. This study reports the first validated reversed-phase high-performance liquid chromatography (RP-HPLC) method for quantifying budesonide encapsulated within poly(lactic-co-glycolic acid) (PLGA)-based, layer-by-layer (LbL) coated nanoparticles intended for colonic delivery in inflammatory bowel disease (IBD). Using response surface methodology with a central composite design, optimal conditions were identified as acetonitrile:water (80:20, v/v) under isocratic mode, achieving complete separation within 5 min at a flow rate of 0.34 mL/min and detection at 244 nm. The method is buffer-free, rapid, and solvent-efficient, resulting in a favorable greenness profile, further confirmed by GAPI and NEMI assessments. Validation in line with ICH Q2(R2) demonstrated excellent linearity (R{superscript 2} > 0.999), precision (%RSD < 2 %), accuracy, specificity, and sensitivity (LOD: 0.04 {micro}g/mL; LOQ: 1.2 {micro}g/mL). Forced degradation studies under acidic, alkaline, oxidative, thermal, photolytic, and photostatic conditions showed that the LbL coating markedly enhanced drug stability, particularly against thermal and photostatic stress, while >75% degradation occurred in alkaline and oxidative environments. In vitro release profiling under simulated gastrointestinal conditions demonstrated sustained, pH-responsive release (20.6% over 48 h), consistent with colonic targeting. This validated, green, and stability-indicating method integrates controlled release assessment with comprehensive performance evaluation, providing a versatile platform for quality control of nanoparticulate drug delivery systems and supporting their progression from formulation development to clinical translation

pharmacology and toxicology↗

bioRxiv2024

Optimising the viscoelastic properties of hyaluronic acid hydrogels through colloidal particle interactions: a response surface methodology approach

Enhancing the viscoelastic characteristics of hydrogel systems through strategic colloidal particle interactions is paramount for their functionality in rectal gel applications. This investigation delves into the synergistic interactions between cationic nanoparticles (CNPs), anionic nanoparticles (ANPs), and composite nanoparticles (NPs) within a hyaluronic acid (HA) hydrogel matrix, employing response surface methodology (RSM) for optimisation. Critical parameters, namely the volume fraction of NPs and oscillatory amplitude, were meticulously calibrated to achieve optimal complex viscosity, as determined by advanced rheometric analysis. The findings reveal substantial effects of CNPs, ANPs, and mixed NPs on the viscoelasticity of the HA hydrogel, with complex viscosity measurements of 490.82 {+/-} 10.57, 214.70 {+/-} 8.96, and 328.46 {+/-} 6.67 mPa{middle dot}s, respectively. The hydrogel system with mixed NPs exhibited a strong concordance with empirical data (R{superscript 2} = 0.9843), validating the predictive precision of the model. Morphological assessments uncovered a highly interconnected network within the HA gel-particle composite, characterised by both densely and sparsely packed porous architectures. This study presents a robust framework for modulating viscoelastic properties in colloidal particle-gel systems, providing pivotal insights for the development of advanced rectal gel formulations.

bioengineering↗

bioRxiv2023

Computational Insights into Colonic Motility: Mechanical Role of Mucus in Homeostasis and Inflammation

Colonic motility plays a vital role in maintaining proper digestive function. The rhythmic contractions and relaxations facilitate various types of motor functions that generate both propulsive and non-propulsive motility modes which in turn generate shear stresses on the epithelial surface. However, the interplay between colonic mucus, shear stress, and epithelium remains poorly characterized. Here, we present a colonic computational model that describes the potential roles of mucus and shear stress in both homeostasis and ulcerative colitis (UC). Our model integrates several key features, including the properties of the mucus bilayer and lumen contents, colonic pressure, and crypt characteristics to predict the time-space mosaic of shear stress. We show that the mucus thickness which could vary based on the severity of UC, may significantly reduce the amount of shear stress applied to the colonic crypts and effect colonic content velocity. Our model also reveals an important spatial shear stress variance in homeostatic colonic crypts that suggests shear stress may have a modulatory role in epithelial cell migration, differentiation, apoptosis, and immune surveillance. Together, our study uncovers the rather neglected roles of mucus and shear stress in intestinal cellular processes during homeostasis and inflammation.

biophysics↗