Functionalized cellulose-based adhesive with epoxy groups having high humidity resistance performance.

Sustainable and environment friendly natural-based adhesive has been considered as an optimum alternative of industrial adhesive which is non-renewable and harmful to health. Cellulose is the most abundant natural polymer in nature and has potential applications in the field of adhesives. However, the inherent hydrophilic nature of cellulose-based adhesive significantly challenges its use in high humidity environments. In this paper, a highly hydrophobic and anti-swelling cellulose-based adhesive was prepared by epoxy modification of microcrystalline cellulose (MCC). The simultaneous enhancement of adhesive and cohesive properties is achieved through the reaction of epoxy groups with the hydroxyl groups from the wood and adhesive during the hot-pressing process. Prepared adhesive has excellent properties in extremely humid environments. The dry bonding strength of the prepared adhesive reached 6.02 ± 0.26 MPa, while the wet bonding strength was 4.78 ± 0.21 MPa after immersed in water at 63 °C for 3 h. Furthermore, the bonding strength remained largely stable in 90 % atmospheric humidity. The adhesive has a certain universality, which can bond to substrates such as aluminium, iron, and glass. This study presents an innovative approach to the manufacturing of cellulose-based adhesive with enhanced bonding performance and exceptional water resistance.

Overcoming the structure deficiency of nanodrug coated with tannic acid shell through phenolic hydroxyl protection strategy for Alzheimer's disease combination treatment.

Tannic acid (TA) shell is of great interest for nanodrug design due to its versatile application such as antioxidant, antibacterial, anti-inflammatory. However, evidence is emerging that TA air oxidation in storage stage and unfavorable interactions of TA with electrolyte or protein in drug delivery could bring great challenge for the structure stability of nanodrug. In this study, a smart TA shell of nanomicelles was constructed through phenolic hydroxyl protection strategy, and the antioxidant capacity of nanomicelles maintain stable after 24 days storage. The phenolic hydroxyl protective tannic acid micelles (PHPTA micelles) show excellent performance for combination delivery of azoramide (Azo), dantrolene (Dan), Trazodone (Tra) in accelerated senescence (SAMP8) mice. This study may pave the way for the fabrication of nanodrugs with stable and smart TA shell for oxidative stress relevant diseases.

Combined Core Stability and Degradability of Nanomedicine via Amorphous PDLLA-Dextran Bottlebrush Copolymer for Alzheimer's Disease Combination Treatment.

Nanomedicine faces the challenges of infinite dilution, shear force, biological protein, or electrolyte competition. However, core cross-linking leads to biodegradability deficiency and brings inevitable side effects of nanomedicine on normal tissues. In order to overcome this bottleneck problem, we turn to amorphous poly(d,l)lactic acid (PDLLA)-dextran bottlebrush to emphasize the core stability of nanoparticles, and the amorphous structure offers an additional advantage of fast degradation property over the crystalline PLLA polymer. The graft density and side chain length of amorphous PDLLA together played important influence roles in controlling the architecture of nanoparticles. This effort produces structure-abundant particles, including micelles, vesicles, and large compound vesicles after self-assembly. Here, the amorphous bottlebrush PDLLA was verified to play a beneficial role in the structure stability and degradability of nanomedicines. The codelivery of the hydrophilic antioxidant of citric acid (CA), vitamin C (VC), and gallic acid (GA) via the optimum nanomedicines could effectively repair the SH-SY5Y cell damage caused by H2O2. The CA/VC/GA combination treatment repaired the neuronal function efficiently, and the cognitive abilities of senescence-accelerated mouse prone 8 (SAMP8) recovered.