In this study, we have developed functionalized mono- and dicationic 1,4-diazabicyclo[2.2.2]octane (DABCO) based ionic liquid salts ([C(n)DABCO(+)][Br-] or ([Bz C(n)DABCO(2+)] [2Br(-)]. For the dicationic salts, the nitrogen atoms of DABCO were conjugated to a benzyl group at one end and various long-chain alkyl groups - where n ranged from 10 to 18-at the other end. The interactions of the DABCO salts with ionic liquids such as 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide [Bmim] [Ntf2] and 1-butyl-3- methylimidazolium dicyanamide [Bmim] [DCA] were examined computationally. As proof of concept, the most optimal DABCO salts were synthesized and their gelation ability with ionic liquids [Bmim] [Ntf2] and [Bmim] [DCA] was examined. Our results indicate that the length of alkyl chains of the DABCO salts as well as the anionic component of the ionic liquids played a key role in the gelation process. The DABCO salts with n > 12 formed gels more efficiently in the presence of [Bmim] [Ntf2], while [Bmim] [DCA] gels were formed when n > 14. Furthermore, the dicationic DABCO salt gels were found to form nanofibers or nanowires in the presence of [Bmim] [Ntf2] while the [Bmim] [DCA] gels exhibited gelatinous structures. The monocationic DABCO salts formed dense nanorods or nanofibrillar structures regardless of the ionic liquid components. The thermal properties of the gels indicated that overall the gels formed with [Bmim] [Ntf2] showed higher stability. Additionally, we explored the ability of the gels to extract the environmental pollutant dye methyl orange. Our results indicated that the gels were able to extract the dye efficiently and thus may be potentially developed for trapping environmental pollutants from industrial waste. This study provides a better understanding of the interactions occurring between the DABCO salts and the ILs [Bmim] [DCA] and [Bmim] [Ntf2] and may open new doors for developing nanoscale gelatinous structures for applications in environmental remediation.
Poly(vinyl alcohol) (PVA) is constrained by its low thermal resistance, high water solubility, and moderate mechanical strength, limiting its use in advanced applications. To overcome these issues, a novel, one-step bio-based modification of PVA was developed using starch, malic acid, and phthalic anhydride. The resulting biocomposite film (PVA+) is transparent, flexible, and exhibits significantly enhanced properties. Thermogravimetric analysis showed a 60 degrees C improvement in decomposition temperature to 297.8 degrees C. Mechanical testing revealed percent of extension increase from 262.00 +/- 3.92% to 371.00 +/- 6.65%, while force of strain increase from 42.000 +/- 1.829 N to 54.00 +/- 1.398 N. Furthermore, the film demonstrated complete insolubility in common organic solvents while maintaining 30% biodegradability over 90 days. This sustainable approach effectively enhances the performance of PVA without the use of toxic cross-linkers.
Clobetasol propionate, a topical glucocorticoid, is commonly used to treat inflammatory skin conditions, including atopic dermatitis and psoriasis. However, prolonged use offers risks to patients. This study evaluated the influence of diverse gel-forming polymers (hydroxypropyl methylcellulose, xanthan gum, and chitosan, at 2%) for clobetasol cutaneous delivery (0.05% drug). The formulations were characterized in terms of their appearance, pH, spreadability, rheology, and in vitro drug release. Cutaneous performance, including ex vivo skin permeation and retention (intact and injured skin), in vitro skin adhesion and cytotoxicity, was evaluated. All hydrogels demonstrated favorable characteristics, with a pH of approximately 4. Viscosity did not significantly affect the release rate, which was sustained for 24 h across formulations. Xanthan gum was considered the most promising gel, with higher viscosity and shear-thinning properties, as well as enhanced skin adhesion, without increasing permeation into deeper skin layers, which has been observed for chitosan in intact and injured skin. Hydroxypropyl methylcellulose was also capable of retaining the drug in the upper skin layers; however, its low degree of skin adhesion and low viscosity might reduce its clinical applicability. Importantly, all formulations exhibited superior cytocompatibility compared with the drug solution. Overall, the cutaneous performance of xanthan gum hydrogel is expected to reduce systemic exposure and minimize potential adverse effects.
5-fluorouracil (5-FU) is widely used in clinical chemotherapy, but its non-targeted delivery causes severe systemic toxicity, and uncontrolled burst release limits therapeutic efficacy. Existing pH/temperature-responsive hydrogels for 5-FU delivery suffer from low drug loading capacity and unbalanced sustained release performance, failing to meet clinical demands. To develop highly efficient and safe drug delivery carriers, this study employed a green aqueous solution radical polymerization method. Using DEA and AMPS as functional monomers and EGDMA as a crosslinking agent, a dual-response hydrogel PDAE responsive to both temperature and pH was synthesized. Performance testing demonstrated that this hydrogel exhibits excellent mechanical and swelling properties, along with good temperature/pH sensitivity. At a DEA/AMPS molar ratio of 121:9, the gel achieved maximum 5-FU loading capacity (326.84 mg & centerdot;g(-1)) and encapsulation efficiency (16.72%). Under physiological conditions (37 degrees C, pH 7.4), it exhibited a cumulative release rate of 26.34%, consistent with a first-order release model. Hemolysis rate <1.9% and cell viability >87.6% indicate favorable biosafety. The optimized hydrogel addresses the limitations of current 5-FU delivery systems, providing a promising smart carrier for clinical chemotherapy with improved targeting and reduced side effects.
