Search Results (3,736)

Postbiotic and paraprobiotic preparations are increasingly investigated as non-viable microbial-derived components for topical formulation development, offering an alternative to systems containing live microorganisms. However, their physicochemical and biological performance may depend strongly on the polymeric carrier, and direct comparisons of postbiotic and paraprobiotic fractions derived from the same microbial source in different gel matrices remain limited. This study aimed to develop and comparatively evaluate Carbopol^®- and chitosan-based pharmabiotic gel-serums containing Lacticaseibacillus casei-derived postbiotic (PB) and paraprobiotic (PPB) fractions. The formulations were characterized in terms of macroscopic appearance, pH, spreadability, and rheological behavior, and their antimicrobial activity, effects on preformed biofilm biomass, and DPPH radical-scavenging activity were evaluated. Blank Carbopol^® and chitosan formulations and free PB and PPB fractions were included as controls to distinguish formulation-matrix-associated effects from those observed for the complete formulations. The developed gel-serums exhibited homogeneous initial macroscopic characteristics, pH values ranging from 4.22 to 5.66, and pseudoplastic shear-thinning behavior. Among the PB-containing systems, CA-CS-PB exhibited pronounced antimicrobial activity, with inhibition-zone diameters of 18.00 mm against Candida albicans and 19.93 mm against Candida krusei, and MIC values of 1156 μg/mL against both species. CA-CS-PB also reduced preformed Staphylococcus aureus and Pseudomonas aeruginosa biofilm biomass by 92.89% and 87.63%, respectively, and exhibited the highest DPPH radical-scavenging activity (73.50%). Among the PPB-containing systems, CA-C-PPB produced reductions of 94.63% and 93.71% in preformed S. aureus and P. aeruginosa biofilm biomass, respectively. Blank formulations also exhibited measurable biological responses, indicating that the activities of the complete formulations should be interpreted as formulation-level effects rather than being attributed exclusively to the incorporated PB or PPB fractions. Because PB and PPB were incorporated at different concentrations (5% and 1% w/w, respectively), these findings should not be interpreted as an equivalent-dose comparison of their intrinsic biological potency. Overall, the findings demonstrate the feasibility of incorporating L. casei-derived PB and PPB fractions into different polymeric gel-serum systems and highlight the influence of both the pharmabiotic fraction and carrier matrix on formulation performance. These results support further investigation of these systems as topical formulation platforms; however, storage stability, release behavior, compositional characterization, and skin-relevant safety and performance require further evaluation before dermocosmetic or dermatological applicability can be established. Full article

The development of sustainable structural materials has driven interest in renewable plant fibers as alternatives to synthetic reinforcements. In this study, the structural, thermal, mechanical, and chemical characteristics of Cyperus papyrus fibers were comprehensively evaluated to assess their potential as reinforcement materials for polymeric composites. The fibers exhibited an average diameter of 164.87 µm, with tensile strength and Young’s modulus values of 141.95 ± 89.33 MPa and 11.15 GPa, respectively. Scanning electron microscopy revealed a rough and irregular surface morphology characteristic of untreated lignocellulosic fibers. X-ray diffraction analysis indicated a crystallinity index of 70.15%, while thermogravimetric analysis demonstrated stability up to 220 °C. Chemical composition analysis revealed high α-cellulose content (63.3%) and moderate lignin levels, contributing to a balance between stiffness and processability. The significant relationship observed between fiber diameter and tensile behavior, together with the structural, chemical, and thermal characteristics of the fibers, provides a broader understanding of the structure–property relationships relevant to their potential use as sustainable reinforcement materials. Overall, C. papyrus fibers represent a promising bio-derived material for environmentally conscious engineering applications. Full article

Plant-derived bioactives offer diverse pharmacological activities, but their development is often limited by poor aqueous solubility, instability, rapid metabolism, and low tissue exposure. This review examines delivery platforms used to address these constraints, including liposomes, solid lipid nanoparticles, nanostructured lipid carriers, phytosomes, niosomes, polymeric and protein-based carriers, extracellular vesicles, and self-assembled polyphenol systems. The platforms are compared according to payload compatibility, loading and release behavior, biological barriers, manufacturing requirements, and formulation-specific safety risks. Though carriers of natural origin offer a sustainable and often less toxic alternative, their ability to induce immunogenicity, organ accumulation, and repeated-dose toxicity require product-specific assessment. The review also discusses sustainable extraction and formulation, emphasizing that green performance depends on the entire process rather than on the feedstock alone. Preclinical studies frequently report improved stability, exposure, or therapeutic activity, whereas human evidence remains limited and is concentrated in early-phase studies of curcumin and silybin formulations and a small number of plant-derived extracellular-vesicle preparations. Translation will require standardized characterization, defined critical quality attributes, scalable Good Manufacturing Practice-compliant production, batch consistency, comparative pharmacokinetic and toxicological studies, and appropriately powered clinical trials. These considerations support rational carrier selection based on the physicochemical properties of the bioactive, intended route and target, release requirements, and strength of the available evidence. Full article

The development of novel high-performance materials is a key driver of technological progress in biomedicine. To date, polymeric materials have represented one of the most significant advances in addressing a broad range of challenges. Owing to their versatility and tunable properties, polymers have found countless applications, including in highly demanding biomedical fields, particularly when the availability of donor tissue is limited and transplantation is not always a viable option. To overcome these limitations, increasing research efforts have been devoted to the development of tailor-made biocompatible materials capable of restoring physiological functions. Within this context, the present research focuses on the synthesis and characterization of innovative aromatic polyesters containing polar comonomeric units to enhance their hydrophilicity. The reference homopolymer, poly(pentamethylene naphthalate), was chemically modified by incorporating different molar amounts of dimethyl 5-sulfoisophthalate subunits, with the aim of improving surface wettability and biological integration. In addition to high thermal stability and processability, the resulting materials exhibited good optical transparency, with low color saturation and a faint bluish hue, making them potentially suitable for biomedical applications, including the treatment of ocular tissues. Finally, biocompatibility was preliminarily assessed through in vitro cytotoxicity tests. Overall, these findings may lay the foundation for developing a new generation of materials capable of providing advanced solutions for biomedical applications. Full article

Despite the robust mechanical and chemical stability that make hollow flat-sheet ceramic membranes highly attractive for membrane bioreactors (MBRs), the fundamental relationship between their structural design, specifically pore size and structural symmetry, and biological fouling behavior remains elusive. To decouple the effects of membrane architecture on fouling mechanisms, a series of symmetric and asymmetric hollow flat-sheet alumina membranes were systematically engineered. Symmetric architectures with tunable pore sizes were fabricated by controlling aggregate particle sizes, whereas asymmetric counterparts featuring distinct separation layer thicknesses were developed via a tailored dip-coating process. Long-term operational evaluations treating municipal wastewater uncovered a counterintuitive phenomenon. Asymmetric membranes, despite yielding superior retention, experienced markedly accelerated transmembrane pressure evolution and severe cake layer fouling compared to the symmetric supports. Resistance-in-series analysis coupled with classical filtration models demonstrated that thicker separation layers and larger pore sizes were associated with shifts in the dominant fouling mechanism toward rapid and dense cake layer formation, which significantly exacerbated irreversible biological fouling. Furthermore, advanced spectroscopic and high-throughput sequencing techniques revealed that structurally complex asymmetric layers were associated with shifts in extracellular polymeric substances and specific fouling-associated bacterial phyla at the membrane interface. Ultimately, these findings underscore the necessity of architectural optimization to mitigate biofouling and prolong the operational lifespan of ceramic membranes, highlighting the sustainable advantages of symmetric structures. Full article

The uniformity of polymer matrices can strongly influence pattern retention during negative-tone development. In this study, two 3-arm star terpolymers, designated HTM Random and HTM Block, were synthesized via reversible addition–fragmentation chain transfer polymerization using simultaneous and sequential monomer-addition strategies, respectively. Both polymers were prepared using the same nominal feed ratio of 2-hydroxyethyl methacrylate, dicyclopentanyl methacrylate, and 2-methyl-2-adamantyl methacrylate. Although the two materials exhibited controlled molecular weight distributions and similar FT-IR spectral changes after ultraviolet exposure and post-exposure baking, differences were observed in their chain-packing characteristics, thermal behavior, and developed pattern morphology. The two materials exhibited comparable initial thermal stability but distinct multistep degradation profiles and glass-transition behavior. In contrast, the simultaneous-feed material showed more clearly retained and spatially uniform patterns under the tested development conditions. These results indicate that the materials produced by the two monomer-addition strategies exhibited differences in thermal response and development behavior under the investigated conditions. Full article

Polymeric drug carriers have emerged as versatile platforms for improving therapeutic efficacy, drug stability and controlled and sustained release of active pharmaceutical ingredients. Conventional manufacturing techniques often rely on high processing temperatures, utilization of organic solvents and consequent purification procedures that may compromise morphology, encapsulation efficiency and carrier biocompatibility. Supercritical fluid technologies overcome the limitations of conventional methods and emerge as environmentally friendly, sustainable and flexible alternatives to produce advanced polymeric drug carriers. This review provides insights into the most widespread supercritical fluid technologies, encompassing the most recent advancements (2022–2026) made in the field of porous materials, micro- and nanoparticles and microcapsules. Emphasis was placed on carrier characteristics, features and applicative translation; this review aims at evidencing advantages, current limitations and future perspectives of supercritical fluid technologies, aiming at encouraging technological and industrial advancement of next-generation advanced polymeric drug carriers. Full article

A series of boron-functionalised exo-norbornene monomers bearing boronic ester groups were synthesised via a condensation reaction and subsequently polymerised through ring-opening metathesis polymerisation (ROMP) to afford well-defined poly(norbornene-B-arylene-dioxaborepine)s. The incorporation of Lewis acidic boron centres into the norbornene-derived polymer backbone enables access to coordination-active macromolecular systems with tuneable interactions towards nucleophilic species. The resulting polymers demonstrate enhanced structural definition and stability, thereby confirming the robustness of the synthetic approach and the successful incorporation of boron functionalities into ROMP-derived architectures. This work establishes a general and efficient strategy for the preparation of boron-containing ROMP polymers, providing a versatile platform for the development of coordination-responsive polymeric materials. Full article

Polymeric micelles represent a fundamental self-assembled architecture of gel-based soft materials and have emerged as promising nanocarriers for anticancer drug delivery. Their performance is largely governed by the block composition of constituent copolymers, and understanding their self-assembly behavior provides critical insights into the rational design of gel-related drug delivery systems. In this work, dissipative particle dynamics (DPD) simulations were performed to systematically investigate two types of mixed drug-loaded micellar systems self-assembled from a triblock copolymer mPEG-b-poly(2-(diethylamino)ethyl methacrylate)-b-PMMA (PDEAEMA, hereafter referred to as the DMA block for brevity) with either a diblock copolymer PDEAEMA-b-PMMA (polymer B) or PPEGMA-b-PDEAEMA (polymer C). By tailoring the ratios of hydrophobic (MMA, the constituent block of PMMA) and pH-sensitive (DMA) blocks, the protonation-responsive behavior, structural stability, drug loading capacity, and release kinetics of the micelles were comprehensively examined. The simulation results demonstrate that: (1) increasing the hydrophobic block ratio accelerates the protonation-triggered micellar swelling and drug release because the increased hydrophobic content enhances the core compactness which, upon protonation, generates a stronger driving force for chain extension, yet an optimal ratio (+16 MMA units) exists beyond which excessive hydrophobic blocks suppress release due to core densification; (2) increasing the pH-sensitive block ratio significantly enhances the maximum drug loading capacity (from 9.83% to 12.22% for the A/C system), but exerts only limited influence on the release rate; (3) the A/C mixed micelles with higher PEG content exhibit superior structural stability and drug loading capacity, while the A/B system with higher MMA content displays more sensitive pH-responsiveness. These findings reveal a competing mechanism between “protonation-driven force” and “structural resistance,” providing mesoscopic theoretical guidance for the rational design of pH-responsive polymeric nanocarriers and self-assembled soft materials via block ratio modulation. Full article

Polyurethane (PU) is widely used in construction, transportation, automotive products, decorative materials, and related industries because its molecular structure can be tailored to diverse service requirements. This versatility has stimulated growing interest in polyurethane-modified asphalt for pavement engineering. This review examines the chemical structure, reaction mechanisms, and principal synthesis routes of polyurethane-modified asphalt and discusses polyurethane-modified emulsified asphalt, polyurethane composite-modified asphalt, and polyurethane-modified asphalt mixtures. Engineering applications in permeable pavements, bridge and tunnel surfacing, as well as crack and pothole repair are also considered. The review further addresses green in situ polymerization, high-content polyurethane systems, waterborne polyurethane, interfacial adhesion, bio-based formulations, recycled asphalt mixtures, and life-cycle performance. The available evidence indicates that polyurethane can improve high-temperature stability, durability, fatigue resistance, mechanical strength, adhesion, and aging resistance. In suitable formulations, it can also reduce production temperatures and construction-related emissions. Economic feasibility, unresolved technical issues, and future research priorities are discussed at the end of the review. Full article

This study numerically investigates the influence of strut diameter on the deployment behavior of a balloon-expandable biodegradable stent with rhombic cell architecture using finite element analysis. The stent material was represented by a 60/40 poly(lactic acid)/polydioxanone (PLA/PDO) blend. Four stent configurations with strut diameters of 0.15, 0.25, 0.35, and 0.50 mm were analyzed under identical deployment conditions. The numerical evaluation considered von Mises stress together with five deployment indicators: diametral strain, elastic recoil, dog-boning, foreshortening, and longitudinal retraction. The results show that increasing the strut diameter reduces elastic recoil, foreshortening, and longitudinal retraction, thereby enhancing post deployment dimensional stability. However, thicker struts also increase the dog-boning effect, indicating less uniform radial expansion. Among the investigated designs, the stent with a 0.35 mm strut diameter showed a balanced response between deployment uniformity and post deployment mechanical stability under the adopted numerical assumptions. For this configuration, elastic recoil, foreshortening, longitudinal retraction, and dog-boning were approximately 6.2%, 10%, 37%, and 8.9%, respectively. These findings provide practical design guidance for biodegradable polymeric vascular stents. Full article

Resveratrol (RSV) is a naturally occurring polyphenol with well-documented antioxidant, anti-inflammatory, antimicrobial, photoprotective, wound-healing, depigmenting, and anticancer properties, making it an attractive candidate for dermocosmetic and dermatological applications. However, its clinical translation into effective topical products remains limited by poor aqueous solubility, chemical instability, photoisomerization, rapid cutaneous metabolism, and restricted skin penetration, all of which compromise local bioavailability and therapeutic efficacy. This narrative review critically examines the molecular mechanisms underlying the cutaneous effects of RSV and discusses how its physicochemical and pharmacokinetic characteristics influence topical performance. Particular emphasis is placed on advanced delivery strategies developed to overcome these limitations, including lipid-based nanocarriers, polymeric nanoparticles (NPs), nanofibers, inorganic nanocarriers, microneedles, hydrogels, and other emerging delivery platforms. The mechanisms by which these systems improve RSV solubility, stability, controlled release, skin retention, and dermal penetration are critically evaluated together with their reported therapeutic outcomes. Although advanced delivery systems have consistently improved the topical performance of RSV in preclinical studies, clinical evidence remains limited. To date, only one published placebo-controlled clinical trial has specifically evaluated topical RSV as the active ingredient, and none of the advanced RSV-nanocarrier platforms discussed in this review has undergone clinical evaluation. Bridging this substantial translational gap will require not only further optimization of formulation design but also scalable manufacturing, rigorous clinical validation, and regulatory pathways capable of supporting the development of safe, effective and evidence-based next-generation dermocosmetic and dermatological products. Full article

The integration of enzyme-loaded polymeric matrices with carbon-based nanomaterials and metallic nanoparticles into wearable multisensing patches, coupled with miniaturized portable detection devices, enables real-time, highly sensitive, and simultaneous monitoring of key clinical biomarkers (e.g., glucose, lactate, and H₂O₂) in clinical and point-of-care applications. Multiplex biosensors were fabricated by modifying screen-printed carbon paste electrodes (SPEs) with different composite nanomaterials based on carbon nanomaterials such as multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs), or fullerenol (FL), the redox mediator Prussian Blue, and platinum nanoparticles (PtNPs). Chitosan and sol–gel polymer matrices were used to immobilize the enzymes glucose oxidase (GOx) and lactate oxidase (LOx), thus ensuring not only increased sensitivity and operational stability, but also high specificity for biomarker detection (glucose and lactate). Among the nanomaterials used for the development of multiplex biosensors, the SWCNT-PtNP composite was highlighted by electrochemical studies as having a significantly superior electrocatalytic activity toward the reduction of H₂O₂. This reaction occurs at a low applied potential of only −0.2 V vs. Ag/AgCl, achieving a specific sensitivity of 224.6 mA·M⁻¹·cm⁻², over a concentration range of 0.07 to 28.26 mM, and a detection limit of 3.2 μM. When functionalized with enzymes, SWCNT-PtNP-based biosensors exhibit improved conductivity, allowing the detection of glucose and lactate at a potential of −0.05 V vs. Ag/AgCl. The specific sensitivities obtained are 20.25 mA·M⁻¹·cm⁻² for glucose and 94.76 mA·M⁻¹·cm⁻² for lactate, and the corresponding detection limits are 23.6 μM and 5.0 μM, respectively. Finally, a wearable patch integrating the multiplex (bio)sensor with a portable potentiostat enabled simultaneous, sensitive, and selective detection of glucose, lactate, and H₂O₂ in sweat samples. Full article

Dental resin composites are widely used for direct restorations, yet their longevity remains limited by biofilm accumulation and secondary caries at the tooth–restoration interface. Unlike previous reviews that have primarily organized antibacterial dental materials according to antimicrobial agents or mechanisms, this narrative review evaluates antibacterial resin composites from a polymer-composite design perspective, integrating molecular architecture, network immobilization, filler–matrix interactions, polymerization, and aging. Leachable agents such as chlorhexidine provide early antibacterial effects but are constrained by reservoir depletion, water sorption, and release-related material changes. In contrast, covalently immobilized quaternary ammonium monomers provide sustained surface-associated activity without continuous release, although their performance depends on molecular structure, concentration, degree of conversion, and network properties. Antibacterial nanoparticles and bioactive glass fillers provide composition-dependent ion-mediated, photocatalytic, pH-modulating, and remineralizing effects, while their performance depends strongly on particle characteristics, dispersion, and formulation. Multifunctional systems further combine antibacterial activity with protein repellence, mineral protection, and rechargeable ion release. Overall, the evidence indicates that durable antibacterial performance cannot be considered independently of polymerization, mechanical integrity, aging stability, and biocompatibility. Future development should therefore prioritize clinically relevant multispecies biofilm models, standardized aging protocols, structure–property analysis, and long-term in vivo and clinical validation. Full article

A molecularly imprinted polymer (MIP)-based quartz crystal microbalance (QCM) sensor was developed for the selective detection of promethazine (PMZ) through deliberate regulation of template–monomer interactions during the molecular imprinting process. Various functional monomer systems were systematically evaluated to optimize intermolecular recognition, among which the combination of 4-vinylpyridine (4-VP) and 2-acrylamido-2-methylpropanesulfonic acid (AAMPS) exhibited the strongest interaction toward PMZ. Furthermore, protonation of PMZ using hydrochloric acid significantly enhanced electrostatic complexation between the template and functional monomers, leading to improved pre-polymerization organization, more effective imprinting-site formation and high selectivity towards target analytes. The resulting MIP-QCM sensor exhibited a linear response toward PMZ over the concentration range of 50–2000 ppb with a correlation coefficient (R²) of 0.99148 and a detection limit of 27.4 ppb. The sensor demonstrated favorable selectivity against structurally related compounds, strong anti-interference performance under highly competitive matrix conditions, and excellent regeneration stability, retaining 97.9% of its original response after ten regeneration cycles. Recovery studies in spiked tap water and carbonated beverage samples yielded recoveries ranging from 94.7% to 112.6%. These results demonstrate that regulating template ionization and template–monomer interactions is an effective strategy for improving imprinting-site quality and molecular recognition performance. The proposed approach provides new insight into the rational design of highly selective MIPs for basic pharmaceutical compounds and offers a promising platform for environmental, pharmaceutical and forensic monitoring applications. Full article