Search Results (456)

The transition toward renewable and environmentally responsible materials has intensified interest in cellulose-based systems for use in sustainable packaging applications. Although cellulose offers biocompatibility, structural versatility, and tuneable physicochemical properties, conventional modification routes rely on harsh chemicals and generate environmentally burdensome effluents. In this study, an efficient and a potentially green strategy for cellulose modification was developed using acid-based deep eutectic solvents (DES) composed of choline chloride and lactic, acetic, or citric acid at different molar ratios. Under mild conditions (110 °C, 4 h), DES pretreatment reduced glucan content in sulphite pulp from 99% to 79–93%, depending on the hydrogen bond donor (HBD), while suggesting an apparent increase in relative crystallinity, from approximately 82% to 90%, as estimated by the Segal method. FTIR, XRD, and morphological analyses revealed the disruption of the hydrogen bonding network, enhanced fibrillation, and residual DES-derived functional groups detectable by FTIR. Although DES pretreatment increased structural order, it also reduced enzymatic digestibility due to the higher proportion of crystalline domains. Overall, the results demonstrate that acidic DES constitutes a sustainable and recyclable medium capable of modulating cellulose structure and generating materials with enhanced physicochemical properties. These findings suggest that DES-modified cellulose could serve as a potential reinforcement platform for future biodegradable packaging and bioplastic formulations, enabling the development of high-performance, renewable, and environmentally compliant packaging materials. Full article

To mitigate cracking, pulverization, and surface spalling in ivory fossils caused by long-term burial and environmental erosion, we developed an organic–inorganic composite system based on quaternized carboxymethyl chitosan and nano-hydroxyapatite (QCB-n-HAP). Applied to degraded specimens from the Songzi Museum, this system significantly improved structural stability and long-term preservation. By systematically reviewing the technical limitations of existing conservation materials and accounting for the specific deterioration characteristics of the target fossils, we established a standardized restoration protocol following a “disease diagnosis–material matching–layered reinforcement–performance characterization” workflow. The QCB-n-HAP composite exhibits excellent interfacial compatibility with the organic components of ivory, enabling deep penetration and pore filling through synergistic hydrogen and covalent bonding. It overcomes the shortcomings of both conventional organic and inorganic materials, while offering favorable reversibility and durability. After treatment, the compressive strength of the fossil samples increased by 68%, crack bonding strength reached 1.2 MPa, and the mechanical property retention rate remained 92% after accelerated aging equivalent to five years of environmental exposure. The reinforcement layer could be completely removed without residue by mild treatment with dilute acetic acid for 30 min. This approach provides a novel technical strategy and theoretical reference for the conservation of Quaternary organic paleontological fossils. Full article

The reaction of either the L or D enantiomer of H₂N-C*H(R)CO₂⁻ (R = -CH₂SH cysteine, C; -C(SH)(CH₃)₂, penicillamine, PN; or -CH₂CH₂SH, homocysteine, HC) with an imidazole-4-carboxaldehyde and nickel(II) acetate in methanol yields a single stereoisomer of a thiazolidine (from C or PN) or a thiazine (from HC) nickel complex. Five pairs of enantiomeric products were prepared and characterized by IR, ESI MS, EA, and single crystal structure determination. There is retention of chirality for the thiazolidine and thiazine complexes on ring position 4, C_α of the parent amino acid, and transfer of chirality to the newly generated stereogenic centers, ring positions 3 (the amino acid nitrogen atom, N_AA) and 2 (the aldehyde carbon atom, C_ald). For the thiazolidines, the new stereogenic centers, N_AA, and C_ald, have identical stereochemical assignments to one another and to the assignment of the alpha carbon atom, either all R from the L enantiomers of C and PN or all S from the D enantiomers of C and PN. For the thiazine products from HC, the newly generated stereogenic centers, ring positions 3 (N_AA) and 2 (C_ald), are identical to one another but opposite to that of the retained stereogenic center (ring position 4, the alpha carbon atom). Regardless of stereochemical assignment (R or S), the hydrogen atoms of C_α, N_AA, and C_ald, ring positions 4, 3, and 2, are always all cis to one another for the five pairs of enantiomers examined. This is a consequence of the fact that the thiazolidine and thiazine rings are fused to two other chelate rings of the complexes, which seems to explain the high stereospecificity observed in these systems. Full article

According to the “Technical Specification for Air Quality Testing in Archives Repositories,” air pollutants in archives can be categorized into exogenous and endogenous pollutants. Common exogenous pollutants include sulfur dioxide (SO₂), nitrogen dioxide (NO₂), ozone (O₃), and hydrogen sulfide (H₂S), while endogenous pollutants mainly consist of formaldehyde (HCHO) and acetic acid (CH₃COOH). This study combines external electric field technology with density functional theory (DFT) and the B3LYP method to theoretically analyze the spectral characteristics and degradation mechanisms of these six pollutant gases. Molecular models of the six gases were constructed using Gaussian software. The configurations of five pollutant gas molecules (SO₂, NO₂, O₃, H₂S, and HCHO) were optimized using the B3LYP/6-31G(d) basis set, while the configuration of acetic acid was optimized using the B3LYP/3-21G basis set, yielding their stable structures and spectral information. The study found that characteristic peaks in the spectra shifted under the influence of an electric field. Additionally, by scanning the potential energy surfaces of selected molecular bonds under varying electric field strengths along specific directions, the required external electric field strengths for the degradation of the six common pollutant gases in archives were determined as follows: 0.1050 a.u. for SO₂, 0.0975 a.u. for NO₂, 0.0925 a.u. for O₃, 0.1000 a.u. for H₂S, 0.1500 a.u. for HCHO, and 0.0705 a.u. for CH₃COOH. The results clarify the degradation thresholds of these six pollutant gases under an external electric field. The findings indicate that acetic acid (0.0705 a.u.) and ozone (0.0925 a.u.) are highly sensitive to electric fields, while formaldehyde requires the strongest electric field (0.1500 a.u.) for degradation. These results provide a reference and theoretical foundation for electric field-assisted degradation technology targeting pollutant gases in archives. Full article

Deep eutectic solvent (DES) extraction is a green and efficient technology. As a substitute for organic reagents, DESs are widely used to extract active ingredients from traditional Chinese medicine. This study established an environmentally friendly and efficient method for extracting astaxanthin (AST) from Phaffia rhodozyma (PR) using ultrasound-assisted deep eutectic solvents (DESs-UAE). The astaxanthin content was determined by high-performance liquid chromatography (HPLC). Six types of deep eutectic solvents composed of DL-menthol and selected hydrogen bond donors were prepared and evaluated, among which the DL-menthol–acetic acid system showed superior extraction performance. Response surface methodology (RSM) was employed to optimize extraction parameters (ultrasonic power, time, and temperature), and the optimal conditions were determined as follows: ultrasonic power 420 W, ultrasonic time 20 min, and ultrasonic temperature 60 °C, achieving an AST extraction rate of 62% (2.49 mg/g). Compared with conventional organic solvent extraction, DESs exhibited a significantly higher AST extraction rate from PR, except for dimethyl sulfoxide (DMSO). Scanning electron microscopy (SEM) analysis demonstrated that DES-UAE treatment disrupted the cellular structure of PR, resulting in numerous surface pores; this facilitated the release of intracellular bioactive components and significantly improved AST extraction efficiency. The PR extract showed no significant cytotoxicity and could effectively promote L929 cell proliferation. It concentration-dependently increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) content in H₂O₂-induced oxidative stress L929 cells, thereby alleviating oxidative damage. Additionally, it concentration-dependently upregulated type I collagen expression in these cells, ameliorated the decline in collagen synthesis function, and exerted a protective effect against cellular oxidative damage. This study provides a green alternative to toxic solvents and offers important theoretical and chemical support for the extraction of natural products and the high-value utilization of Phaffia rhodozyma (PR). Deep eutectic solvents have emerged as promising green alternatives to hazardous organic solvents, yet hydrophobic DESs tailored for lipophilic astaxanthin extraction from Phaffia rhodozyma and the linkage between extraction performance and anti-aging bioactivity remain insufficiently explored. Here, an ultrasound-assisted hydrophobic deep eutectic solvent extraction strategy was constructed to acquire astaxanthin, aiming to overcome low efficiency and environmental risks of conventional organic extraction techniques. Six DL-menthol-based DESs were prepared and screened, and DL-menthol–acetic acid possessed the optimal extraction capacity. Key extraction parameters were optimized via response surface methodology, and the maximum astaxanthin extraction recovery reached 62% (2.49 mg/g) under 420 W ultrasonic power, 20 min treatment and 60 °C. This yield was markedly higher than that of most common organic solvents; though comparable extraction effect was obtained with DMSO, the adopted DES possessed outstanding low-toxic and biodegradable superiorities that DMSO cannot match. SEM characterization verified that the combined treatment destroyed yeast cell structure and formed porous morphology, which accelerated intracellular astaxanthin release and accounted for improved extraction efficiency. Biological assays proved the extract possessed good biosafety and proliferation-promoting effect on L929 cells. It effectively relieved cellular oxidative injury by elevating the SOD level and reducing MDA accumulation in oxidative damaged cells, and upregulated type I collagen expression to mitigate aging-related collagen loss. This work develops an eco-friendly and high-efficiency extraction route for lipophilic active substance, confirms the practical value of hydrophobic DES, and provides experimental basis for high-value utilization of Phaffia rhodozyma resources. Full article

The valorization of agri-food by-products generated during juice extraction represents a key strategy within circular economy frameworks, as it reduces the environmental impact of waste disposal while creating added value and improving the food supply chain. In this work, five betaine-based natural deep eutectic solvents (NaDES) differing in their hydrogen-bond donors, namely citric acid, lactic acid, acetic acid, glycerol, and ethylene glycol, were used for the green extraction of blueberry pomace, a largely underutilized by-product that is nevertheless rich in bioactive compounds. The extracts were characterized by liquid chromatography coupled with diode-array and tandem mass spectrometric detection, allowing targeted profiling of anthocyanins and non-anthocyanin phenolics, including phenolic acids, flavonoids, and phenolic aldehydes. The extraction performance of NaDES was benchmarked against conventional solvents (water and ethanol) to evaluate differences in selectivity and efficiency toward distinct phenolic classes. Antioxidant capacity was determined using DPPH and ABTS radical scavenging assays. Among the NaDES systems, the betaine–citric acid NaDES extract exhibited notable phenolic recovery together with marked radical scavenging activity. After evaluating its inhibitory activity against elastase and tyrosinase, enzymes involved in the skin aging process, the selected NaDES extract was incorporated into a natural-based antiaging cosmetic formulation, and its main physicochemical properties were assessed to verify suitability for topical application. This study demonstrated that the use of NaDES represents an environmentally friendly and sustainable approach to transform blueberry by-products into high-value, safe, and ready-to-use cosmetic functional ingredients without the need for solvent removal. Full article

Drought stress is one of the most severe constraints affecting wheat production worldwide. Under these conditions, the development of sustainable and economically viable strategies, such as seed priming, is essential to improve wheat performance and drought resilience. The present study carried out a greenhouse experiment on four Mediterranean durum wheat cultivars (Triticum turgidum ssp. durum Desf), i.e., Karim (Kr) and Khiar (Kh) from Tunisia and Espelta (Esp) and Mocho (Mo) from Spain, subjected to drought stress conditions, and using primed abscisic acid (ABA), indole-3-acetic acid (IAA), melatonin (Mlt), and salicylic acid (SA), and non-primed seeds. In order to assess the physio-biochemical responses of durum wheat, such as plant growth, chlorophyll, relative water content (RWC), water potential (Ψw), osmotic potential (Ψs), proline, soluble sugars, starch, glycine betaine, hydrogen peroxide, malondialdehyde, and antioxidant enzyme activities. The results showed that water stress significantly reduced plant growth, SPAD index, RWC, Ψw, and Ψs, while upregulating H₂O₂ and MDA levels, depending on the wheat cultivars. Soluble sugars decreased, whereas starch, glycine betaine, and proline accumulated in all cultivars. Superoxide dismutase activity was reduced (24–37%) under water stress as compared to the control condition, while APX, CAT, and POD activities significantly increased. Among the cultivars, Esp exhibited the greatest plasticity in response to water deficit, whereas Kh appeared to be most sensitive. Furthermore, the present results revealed that the priming durum wheat seeds with ABA, IAA, Mlt, and SA improved leaf hydration, particularly through soluble sugar accumulation. Seed priming also alleviated oxidative stress by reducing H₂O₂ and MDA levels and stimulating APX, CAT, POD, and SOD activities. Plants grown from non-primed seeds of Spanish and Tunisian cultivars exhibited differential responses to drought stress, and those derived from primed seeds showed varying degrees of enhanced drought tolerance. Espelta demonstrated a high potential for stress tolerance and responsiveness to priming, followed by Karim, whereas Khiar was the most sensitive cultivar. Overall, the cultivars can be ranked in decreasing order of stress tolerance as Esp > Kr > Mo > Kh. These findings highlight the potential of phytohormone-based seed priming as an efficient and practical approach to enhance drought resilience in durum wheat, offering promising prospects for improving crop performance and stability under increasingly water-limited conditions in the era of climate change. Full article

Acidogenic fermentation of organic wastes represents a strategic platform for the co-production of H₂, CO₂, and volatile fatty acids (VFAs), which are potential key intermediates for cost-effective polyhydroxyalkanoate (PHAs) biosynthesis. This typically relies on carbon sources that are too expensive and hinder the commercialization of PHAs. This study provides metagenomic insights into the microbial dynamics underpinning the acidogenic conversion of waste melon under increasing organic loading rates (OLRs). Metabarcoding revealed that Megasphaera dominated the community, with its abundance rising markedly from 5 to 20 gCOD/L, accompanied by relevant contributions from Solobacterium, Prevotella, and Clostridium. These taxa were associated with the formation of acetic, propionic, and butyric acids and with enhanced hydrogenogenesis. Higher OLRs, up to 20 gCOD/L, promoted hydrogen-producing species while suppressing lactic acid bacteria, thereby improving H₂ and VFAs yields up to 26.7% v/v and 13 gCOD/L, respectively. By linking microbial shifts to metabolic outputs, this work advances the understanding of acidogenic pathways essential for integrating dark fermentation-derived H₂, CO₂, and VFAs into sustainable PHAs production systems. Full article

Using the gel-grown method to control the morphology of crystals attracts extensive attention. Potassium dihydrogen phosphate (KDP) is a nonlinear optical crystal with a high laser damage threshold. Here, we studied the crystallization of KDP in silica gel. The kebab-like KDP crystals (multiple KDP crystals aligning along a straight line) were prepared in the silica gel. In situ observation revealed that the kebab-like crystals were obtained through secondary nucleations on preformed needle-like crystals. Further investigation revealed that the hydroxyl groups on the gel network have an important influence on the formation of kebab-like KDP crystals. The hydroxyl groups on the gel networks can form hydrogen bonds with the phosphoric acid group of the KDP crystal and hinder the growth of the prismatic KDP faces, which leads to the preformation of needle-like crystals. Additionally, the influence of the acetic acid concentration and antisolvent on morphology was also studied. Full article

Spent coffee grounds (SCGs), a major by-product of coffee consumption, remain an underused source of chlorogenic acid (CGA) and other phenolic constituents. This study investigated an ultrasound-assisted extraction strategy using deep eutectic solvents (DESs) to improve the recovery and phenolic-acid enrichment of SCGs. Among the tested DES formulations, the betaine–acetic acid system gave the best CGA extraction performance and was therefore used for further optimization by response surface methodology. The optimized process, conducted at a liquid-to-solid ratio of 28 mL/g, 75 °C, and 50 min, produced a CGA yield of 15.18 mg CGA/g dried SCG powder, markedly exceeding that achieved with 70% ethanol under comparable conditions. Structural and chemical characterizations helped explain this improvement. Scanning electron microscopy revealed that the DES-based process caused more evident disruption of the SCG matrix, which favored solvent penetration and mass transfer. Fourier-transform infrared spectroscopy confirmed the formation of a hydrogen-bonding network between betaine and acetic acid. Ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry further revealed that the betaine–acetic acid extract was mainly composed of CGA and hydroxycinnamic acid derivatives. The purified extract also displayed strong in vitro antioxidant capacity. Overall, the betaine–acetic acid DES combined with ultrasound provides an effective green approach for recovering CGA-rich phenolic extracts from SCGs. Full article

Background: Momordica balsamina L. is widely used in traditional medicine for the management of diabetes in South Africa and globally. This study evaluated the in vitro antidiabetic and cytotoxic effects of M. balsamina leaf extracts and identified bioactive compounds potentially responsible for its activity. Methods: Leaves were sequentially extracted using solvents of increasing polarity. Phytochemical composition was determined using standard colorimetric assays, while gas chromatography–mass spectrometry (GC–MS) was employed for compound identification. Antioxidant activity was evaluated using dot blot, DPPH radical scavenging, hydrogen peroxide scavenging, and ferric reducing power assays. Antidiabetic potential was assessed using α-amylase, α-glucosidase, and β-glucosidase inhibitory assays, with acarbose as the reference drug. Cytotoxicity was determined by using the MTT assay on Vero and HEK-293 cell lines. Results: Phytochemical screening revealed alkaloids, flavonoids, terpenoids, saponins, glycosides, and steroids. GC–MS analysis identified compounds associated with antidiabetic activity, including vanillin, 2,4-di-tert-butylphenol, oleic acid, phytol, and hexadecenoic acid. All extracts exhibited antioxidant activity, with the ethyl acetate extract showing the strongest effect. Enzyme inhibition was concentration dependent. The dichloromethane and ethyl acetate extracts showed stronger α-amylase inhibition (IC₅₀ = 0.149 and 0.146 mg/mL) than acarbose (0.209 mg/mL). For α-glucosidase, acarbose showed the highest activity, while extracts displayed moderate inhibition. In β-glucosidase assays, both extracts were more active than acarbose. Both extracts were non-cytotoxic up to 500 µg/mL. Conclusions: These findings support the traditional use of M. balsamina and highlight its potential as a safe source of antidiabetic agents, warranting further investigation. Full article

Agronomic biofortification offers an environmentally friendly way to improve crop nutrition. The biofortification of vegetables with iodine has attracted increasing attention due to its significance for human health. Hydrogen sulphide (H₂S) is a gaseous signalling molecule that affects many physiological and biochemical processes in plants. Lettuce (Lactuca sativa L.) plants were cultivated under controlled greenhouse conditions. Foliar applications of potassium iodate (KIO₃) and hydrogen sulphide (H₂S, supplied by sodium hydrosulphide (NaHS)) were applied separately and together (H₂S + KIO₃). Evaluations included growth parameters, photosynthetic pigments, biochemical metabolites, antioxidant enzyme activities, plant hormone levels, and mineral nutrient contents. All treatments resulted in significant changes in plant growth and physiological traits compared to the control. The combined application resulted in greater responses across several parameters; however, these observations do not demonstrate a causal or mechanistic interaction between the treatments. The combined application increased plant fresh weight by ~42% and leaf area by ~35% compared to the control. Total chlorophyll content approximately doubled (≈100% increase), while SOD, POD, and CAT activities increased by up to ~160%, ~13%, and ~40%, respectively. Proline and sucrose contents increased by approximately 100% and 85%. Hormonal changes included increases in indole-3-acetic acid (~44%) and cytokinins (~55%), and a decrease in abscisic acid (~20%). In addition, several macro- and micronutrients in leaves and roots were affected by the treatments. The combined application of KIO₃ and H₂S was associated with greater responses across several measured parameters than either compound alone; however, these observations do not demonstrate a causal or mechanistic interaction between the two compounds. Furthermore, as the experiment was conducted under non-stress greenhouse conditions, the observed physiological responses should be interpreted as changes in metabolic and regulatory processes rather than direct evidence of enhanced stress tolerance. Overall, the results indicate that foliar application of KIO₃ and H₂S can influence growth and physiological traits of lettuce under controlled conditions. Full article

Nowadays, the global demand for medicinal plants, including A. absinthium L. (wormwood), has increased considerably, leading to significant pressure on their wild populations and the biodiversity of ecosystems. Consequently, the rates of exploitation may exceed those of natural regeneration. This destructive process can be reduced by cultivating plants with the desired secondary metabolites by transferring them from their natural habitats. The present study investigates phytochemistry and the potential antioxidative/prooxidant activity of low-thujone A. absinthium plants. The chemical composition of wormwood extracts and essential oils (EOs) was determined by HPLC/DAD/TOF and GC/MS techniques, respectively. Trans-Sabinyl acetate (59.6 ± 10.1%) predominated in the wormwood EOs, while the content of toxic trans-thujone was negligible (1.2 ± 0.5%). Eighteen acids, such as fumaric, ascorbic, succinic, quinic, malic, gallic, benzoic, (neo/iso)chlorogenic, (di)ferulic, caffeic, etc., were found in 50% methanolic wormwood extracts. Additionally, (epi)catechin, astragalin, diosmetin, piceatannol-3’-O-glucoside, quercetin-3-O-glucoside, quercetin-3-O-rhamnoside-7-O-glucoside, hesperidin, apigenin-7-O-glucoside, baicalin, 5,7,3′-trihydroxy-3,6,4′,5′-tetramethoxyflavone and rutin were tentatively identified in the extracts. Total phenolic content was found 412.82 ± 11.10 mg/L (of gallic acid equivalent) in A. absinthium methanolic extracts. Using conventional spectroscopic methods, the antioxidant activity (DPPH radicals scavenging) was determined to be 0.83 ± 0.06 mmol/L (TROLOX equivalent) in the wormwood essential oil. ABTS^●+ and DPPH^● scavenging activity means, 3.485 ± 0.07 (TROLOX, mmol/L) and 6.48 ± 0.25 (TROLOX, mmol/L) were revealed for A. absinthium methanolic extracts. Less commonly used methods, electrochemical tests showed the presence of oxidizable compounds with characteristic E_pa values of 0.38 and 0.61 V. Moreover, hydrogen peroxide scavenging tests were performed. The largest quantity of peroxide (31.86 ± 0.1 μmol/L) was formed in the wormwood boiling infusions (at pH = 7.2). As the presence of toxic and neurotoxic thujone isomers is undesirable, therefore, the search for low- or thujone-free plants from natural populations that exhibit biological activity (i.e., antioxidant/prooxidant) is of great importance. Full article

Seed aging is a key issue that affects the preservation of germplasm resources and crop production. At present, the anti-aging properties of perilla seeds and the mechanisms of differences among varieties have not been clearly reported. This study aims to analyze the mechanisms of changes in storage substances and hormone levels in different varieties of perilla during the artificial aging process. The results show that seed aging can significantly reduce the activity of antioxidant enzymes in perilla seeds, decrease the contents of storage nutrients such as soluble proteins, soluble sugars, and oil content, reduce the accumulation of unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid, and significantly decrease the contents of endogenous Gibberellic acid (GA₃) and Indole-3-acetic acid (IAA). Meanwhile, the levels of hydrogen peroxide (H₂O₂) and Malondialdehyde (MDA) increased significantly, while the contents of saturated fatty acids such as palmitic acid and stearic acid rose, and the contents of endogenous Abscisic acid (ABA), Jasmonic acid (JA), Salicylic acid (SA), and Trans-zeatin riboside (TZR) were significantly upregulated. There are significant genotype differences in the tolerance of different perilla varieties to seed aging. The sensitivity of Shiban Perill (S23014) to aging stress is significantly higher than that of Qisu No. 2 (S23017). This study has confirmed that seed aging has adverse effects on the germination of perilla seeds by down-regulating the activity of antioxidant enzymes, reducing the accumulation of storage nutrients, and disrupting the balance of endogenous hormones. The research results provide an important theoretical basis for the preservation of perilla seed germplasm resources and the selection of anti-aging varieties. Full article

Degenerative joint disease is a major cause of disability, and although glucocorticosteroids and hyaluronic acid are widely used to reduce inflammation and improve joint mobility, the development of effective delivery systems remains a challenge. This study describes injectable sodium hyaluronate (HA)-based hydrogels modified with synthetic polymers, including polyacrylic acid (PA), ammonium acryloyldimethyltaurate/VP copolymer (AX), a polyvinyl acetate–polyvinylpyrrolidone mixture (PVA–PVP), and polyethylene glycol 4000 (PEG), loaded with prednisolone disodium phosphate (PSP). The aim was to investigate molecular interactions between PSP and HA-based polymer networks and to determine how these interactions influence hydrogel structure, viscosity, and drug release. Viscosity was measured using a Brookfield rotational viscometer, while intermolecular interactions were analyzed by ATR–FTIR and DSC. Drug release was evaluated using a paddle-over-disc apparatus and quantified spectrophotometrically. Release kinetics were analyzed using zero-, first-, and second-order models as well as the Higuchi, Korsmeyer–Peppas, and Peppas–Sahlin equations. PSP incorporation affected the dynamic viscosity of all formulations, and excipient type also significantly influenced hydrogel viscosity. ATR–FTIR and DSC analyses indicated hydrogen bond formation between PSP and the macromolecules of HA, PA, AX, and PEG. The PA-containing formulation formed the most extensive polymer network structure and exhibited the highest viscosity. Drug release followed mainly first-order, Higuchi, and Korsmeyer–Peppas models, while the release exponent n (0.58 ± 0.01–0.60 ± 0.01) indicated anomalous transport. These findings provide molecular insight into drug–polymer interactions in HA-based hydrogels and highlight their potential as injectable systems for intra-articular delivery of PSP. Full article