Jul 2026· International Journal of Drug Delivery Technology· Vol 16· 0 citations· 28 references
TL;DR
The results indicate that PLGA nanoparticles offer superior therapeutic efficacy, prolonged drug release, and improved bioavailability as a carrier system for sustained ocular delivery of dexamethasone.
Abstract
The study emphasizes the role of PLGA as a biodegradable polymeric matrix governing drug release
through diffusion and polymer erosion mechanisms, thereby functioning as a polymer–drug nanocomposite
system. The structural and physicochemical properties of the polymer matrix play a critical role in
controlling drug encapsulation and release kinetics. The solvent evaporation technique was utilized to
fabricate PLGA nanoparticles, and a 3² factorial design was implemented for optimization. The optimized
combination exhibited a zeta potential of −21.5 ± 2.6 mV, a polydispersity index of 0.182 ± 0.03, and an
average particle size of 178.6 ± 12.4 nm. The drug loading was determined to be 14.6 ± 1.2%, while the
drug entrapment efficiency was found to be 82.3 ± 3.7%. The biphasic release pattern was demonstrated in
in vitro release studies. The initial burst release transpired within 6 hours, with a release rate of 21.4 ±
2.1%. The second burst release transpired within 72 hours, yielding a cumulative release rate of 88.7 ±
3.5%. Investigations into the permeability of nanoparticles in goat corneas revealed a 1.97-fold
enhancement in the permeability coefficient, with drug infiltration from nanoparticles significantly
exceeding that from drug suspension (68.2 ± 4.3% versus 34.6 ± 3.1%; p < 0.001). In vivo research on the
pharmacokinetics of medicine absorption and ocular residence time in New Zealand albino rabbits (n = 6)
demonstrated that PLGA nanoparticles significantly enhanced both parameters. The nanoparticle
formulation exhibited a peak drug concentration (C_max) of 3.84 ± 0.42 µg/mL in aqueous humor, whereas
the suspension demonstrated a concentration of 1.76 ± 0.28 µg/mL (p < 0.001). The extended duration to
achieve maximum concentration (T_max) (4.0 ± 0.5 h vs. 1.5 ± 0.3 h) indicates a sustained release pattern.
The nanoparticles exhibited a 2.2-fold enhancement in bioavailability, evidenced by a much larger area
under the curve (AUC₀-24h) of 28.6 ± 3.2 µg·h/mL, in contrast to the suspension's 12.9 ± 2.1 µg·h/mL. The
results indicate that PLGA nanoparticles offer superior therapeutic efficacy, prolonged drug release, and
improved bioavailability as a carrier system for sustained ocular delivery of dexamethasone. The study
emphasizes how polymer matrix density, interfacial stabilization, and crystallinity govern diffusion
pathways and degradation-controlled release.
Objectives: The present study designed to prepare and evaluate valacyclovir hydrochloride-loaded hydrogel microbeads using a sodium alginate-xanthan gum polymeric system to get sustained drug release and potential for sustained delivery.
Methods: Microbeads were formulated by the ionic gelation technique using variable ratios of sodium alginate and xanthan gum, cross-linked with aluminum chloride (1% and 2% w/v). The formulations were tested using various evaluation methods, that is, percentage yield, particle size, swelling index, drug entrapment efficiency, surface morphology study by scanning electron microscopy (SEM), drug-polymer compatibility fourier transform infrared spectroscopy (FTIR), and in vitro drug release. Release kinetics were examined by means of various mathematical models.
Results: The microbeads were spherical with rough surfaces, as established by SEM, and exhibited no chemical incompatibility as per FTIR analysis. Particle size ranged from 661.67±10.65 μm to 713.67±12.33 μm, indicating uniformity. Percentage yield (79.80–88.11%) and drug entrapment efficiency (23.26–39.04%) exhibited higher values in alginate-rich formulations. Swelling index ranged between 217.00±20.60% and 304.00±16.77%, affected by polymer ratio along with cross-linking density. In vitro drug release studies confirmed a sustained release profile, with F1 presenting the highest release (40.08%) and F6 the lowest (28.91%) through 300 min. Drug release mainly followed the Korsmeyer-Peppas model, signifying a diffusion-controlled mechanism with polymer relaxation.
Conclusion: The study ensures that physical characteristics along with drug release behavior of the microbead were pointedly influenced by polymer composition in addition to cross-linking concentration. The prepared sodium alginate-xanthan gum system demonstrates potential as an active sustained drug delivery system for valacyclovir hydrochloride.
S. Bhunia, Dipankar Saha, Sudipta Das et al.· Asian Journal of Pharmaceuti...· 0 citations
Polymeric microneedles are introduced as a promising platform for minimally invasive drug delivery and molecular transport control. In the present study, hollow dissolving nanocomposite microneedles based on a mixture of high- and low-molecular-weight hyaluronic acid (HA) in a 40:60 ratio, including zinc oxide nanoparticles (ZnO NPs), have been created and evaluated as hydrated polymer transport matrices. Surface modification of ZnO nanoparticles using citric acid was proposed to improve dispersion by reducing agglomeration of nanoparticles in the polymer matrix. ZnO nanoparticles in concentrations ranging from 1 to 10% (w/w) were used to study the effects of the loading level of nanoparticles on the structure, mechanical response, and controlled diffusion behavior of hydrated polymer matrices. The created nanocomposites exhibited clear hollow structures with tip radius of 18–23 μm, height of 1500 μm, and aspect ratio of 5.7. Nanoscale surface organization and particle dispersion in the polymer matrix were studied by scanning electron microscope (SEM) and atomic force microscope (AFM). Low nanoparticle concentrations were favorable for maintaining high matrix homogeneity, while high concentrations resulted in increased surface roughness and nanoparticle agglomeration. Mechanical compression testing confirmed that hydrated HA/ZnO microneedles were characterized by elastic bending behavior until fracture. Diffusion experiments performed in Franz diffusion cells showed that nanoparticle concentration significantly impacted the cumulative transport and flux of molecules through the hydrated microneedle matrix. Formulations with 5% and 7% ZnO nanoparticles were characterized by a prolonged diffusion behavior attributed to ZnO-induced tortuous transport channels in the polymer matrix. In contrast, formulations with 10% ZnO nanoparticles exhibited accelerated heterogeneous transport due to ZnO-induced changes in structure and morphology. The experimental diffusion data correlated well with the Higuchi kinetic model, and anomalous transport was detected using the Korsmeyer–Peppas model, which indicated a synergistic effect of diffusion and polymer relaxation on molecular transport. As compared to coating and tip-loaded microneedle designs, the obtained HA/ZnO nanocomposite microneedles offered a simple approach for embedding Ciprofloxacin in the hydrated polymer matrix. This was achieved due to the direct creation of microneedles containing dissolved particles.
Kolawole S. Dada, R. Olekhnovich, Faliya F. Zaripova et al.· Macromol· 0 citations
Background: Topical drug delivery systems provide site-specific therapy with reduced systemic exposure. Nanosponges have emerged as promising carriers owing to their porous structure, enabling improved drug stability, bioavailability, and sustained release. Apremilast, a phosphodiesterase-4 (PDE4) inhibitor with anti-inflammatory activity, has potential for topical wound management when formulated as a controlled-release delivery system. Methods: Apremilast-loaded nanosponges were prepared by the emulsion solvent diffusion method using Ethyl Cellulose (EC) and Polyvinyl Alcohol (PVA). A 3² factorial design was used to optimize the EC: PVA ratio and sonication time. Formulations were evaluated for particle size, entrapment efficiency, zeta potential, in vitro drug release, and surface morphology. Characterization included UV spectroscopy, FTIR, XRD, DSC, and SEM. Drug release kinetics were analyzed using mathematical models. Results: Preformulation studies confirmed drug purity and compatibility with excipients. The optimized formulation (NS8) exhibited a particle size of 213.85 nm, an entrapment efficiency of 82.75%, a zeta potential of −33.3 mV, and a sustained drug release of 95.85% over 24 h. SEM revealed spherical porous nanosponges, while FTIR, XRD, and DSC confirmed drug integrity and formulation stability. Response surface analysis demonstrated significant effects of formulation variables on performance. Drug release followed the Higuchi model (R² = 0.987), and the Korsmeyer–Peppas exponent (n = 0.58) indicated anomalous non-Fickian diffusion. Conclusion: Apremilast-loaded nanosponges demonstrated sustained drug release, excellent stability, and favorable physicochemical characteristics, indicating their potential as an effective topical delivery system for wound management. Further ex vivo, in vivo, and clinical studies are required to confirm therapeutic efficacy and safety.
Purnima Rai, A. Rawat· Journal of Applied Pharmaceu...· 0 citations
Biodegradable polymeric coatings improve metallic implant biofunctionality through sustained drug delivery. While Poly (Lactic-Co-Glycolic Acid) (PLGA) is widely used for its biocompatibility, synchronizing polymer degradation with drug release remains a critical challenge to prevent premature drug loss or insufficient efficacy. This research aimed to examine the degradation behavior and release synchronicity of paclitaxel-loaded PLGA coatings on Ti-6Al-4V substrates. Researchers utilized dip-coating for fabrication, characterizing the samples via Nuclear Magnetic Resonance (NMR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). Degradation was evaluated through mass loss and molecular weight evolution in physiological conditions, while hemocompatibility was assessed via platelet adhesion. Results demonstrated that drug incorporation significantly influenced structural and thermal properties. Notably, the research found a near-perfect linear correlation between the reduction in molecular weight [Formula: see text], mass loss [Formula: see text] and cumulative drug release, confirming synchronized kinetics. Furthermore, the coatings exhibited excellent hemocompatibility with minimal platelet activation. In conclusion, these synchronized PLGA coatings provide a reliable, multifunctional platform for long-term therapeutic delivery in next-generation medical implants.
Introduction The present study aimed to develop and evaluate a thermoresponsive in situ gel incorporating Exemestane-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles for sustained drug delivery. Methods Exemestane-loaded PLGA nanoparticles were prepared by nanoprecipitation and characterised for particle size, zeta potential, morphology, entrapment efficiency, and drug release behaviour. Results The nanoparticle exhibited a mean particle size of 257.6 nm, moderate stability with a zeta potential of–15.3mV, high encapsulation efficiency (93.46± 2.46%) and drug loading 27.8±1.2% (0.278±0.012mg Exemestane /mg nanoparticles), indicating successful formulation. The optimised nanoparticles were incorporated into a poloxamer-based thermoresponsive in situ gel system modified with chitosan to enhance gel strength and bioadhesion. The formulation was optimised using a Box–Behnken design, achieving a gelation temperature of 38.3±0.5 °C and gelation time of 0.75±0.5 min, suitable for physiological conditions. In vitro drug release studies demonstrated a sustained release profile with minimal burst effect, achieving approximately 80% drug release over 24 hours. Release kinetics followed the Korsmeyer–Peppas model, indicating an Fickian and diffusion mechanism governed by both diffusion and polymer erosion.The formulation exhibited desirable physicochemical properties, appropriate rheological behaviour, controlled gel erosion, and stability over three months.Ex vivo and HET-CAM studies indicated reduced angiogenesis, suggesting potential therapeutic efficacy in breast cancer treatment. Discussion Overall, the developed nanoparticle-loaded thermoresponsive in situ gel represents a promising localised sustained drug delivery platform for Exemestane and warrants further evaluation in appropriate cellular and in vivo breast cancer models.
Priya Singh, Namrata Swain, Shagufa Shamim et al.· Frontiers in Oncology· 0 citations
The present study aimed to develop and evaluate Anastrozole-loaded mucoadhesive microspheres for sustained oral drug delivery using Sodium CMC, Chitosan, and HPMC K4M polymers. Microspheres were prepared by the solvent evaporation method and characterized for their micromeritic properties, percentage yield, drug entrapment efficiency, swelling behavior, mucoadhesion, surface morphology, and in vitro drug release. The prepared formulations exhibited satisfactory flow properties with particle sizes ranging from 420.15 to 468.41 µm. Percentage yield and drug entrapment efficiency were found to be in the ranges of 88.31–99.52% and 87.14–99.82%, respectively. The microspheres demonstrated excellent swelling and mucoadhesive characteristics, indicating their suitability for prolonged gastrointestinal residence. In vitro dissolution studies revealed sustained drug release for up to 12 h, with cumulative drug release ranging from 85.87% to 99.92%. Among all formulations, A6 containing Chitosan at a drug-to-polymer ratio of 1:2 showed the most desirable performance, achieving 99.92% drug release with superior mucoadhesion and controlled-release characteristics. FTIR studies confirmed the absence of significant drug–polymer interactions, while SEM analysis revealed discrete and spherical microspheres with smooth surface morphology. Drug release kinetic analysis demonstrated that the optimized formulation followed Zero-order kinetics with a non-Fickian diffusion mechanism. The findings suggest that Chitosan-based Anastrozole microspheres are a promising sustained-release oral delivery system capable of improving therapeutic efficacy and patient compliance in breast cancer management.
Prabhu.C, V. Sathyanathan, Antony Jose A et al.· World journal of pharmacy an...· 0 citations