Injectable Self-Healing Ceria-based Nanocomposite Hydrogel with ROS-scavenging Activity for Skin Wound Repair

Excessive reactive oxygen species (ROS) in the injured skin may impede the wound repair and skin regeneration. Herein, we develop an injectable self-healing ceria-based nanocomposite hydrogel with ROS-scavenging activity to accelerate wound healing. The nanocomposite hydrogels were successfully prepared by coating cerium oxide nanorods with polyethylenimine (PEI) and crosslinked with benzaldehyde-terminated F127 (F127-CHO) through the dynamic Schiff-base reaction (FVEC hydrogel). The results showed that the FVEC hydrogel possessed the good thermosensitivity, injectability, self-healing ability and ROS scavenging activity. The subcutaneous implantation experiments in mice confirmed that FVEC hydrogels are biocompatible and biodegradable in vivo. The full-thickness skin wound studies showed that FVEC hydrogel could significantly enhance the wound healing and epithelium regeneration with the formation of hair follicle and adipocyte tissue. This work provides a new strategy for the development of multifunctional Ce-based nanocomposite hydrogel for full-thickness skin wound healing and regeneration.

PHYSICO-CHEMICAL PROPERTIES OF A NANOCOMPOSITE HYDROGEL COATING ON A TEXTILE CARRIER FOR THE WOUND TREATMENT

Нанотехнологии с использованием биополимеров находят широкое применение в биомедицинских приложениях. В данной работе разработаны нанокомпозитные гидрогели на основе природных (хитозан, карбоксиметилцеллюлоза) и синтетических (поливиниловый спирт) полимеров с наночастицами серебра для нанесения на текстильный носитель. В качестве сшивающих реагентов при создании гидрогелей использовали диальдегид карбоксиметилцеллюлозы и борную кислоту. Были определены физико-химические свойства (сорбционная способность при одностороннем контакте с модельной средой, степень набухания, паропроницаемость, капиллярность) гидрогелевых покрытий на текстильном носителе, и кинетика выхода лекарственных веществ (лидокаин, диоксидин), включенных в состав гидрогелей. Показано, что материалы с двухслойным покрытием характеризуются более высокими сорбционными свойствами по отношению к физиологическому раствору и более длительным выходом лекарственных средств, чем материалы с однослойным покрытием. Выход лекарственных веществ из двухслойных покрытий происходит в два этапа с максимальным высвобождением в течение двух суток. Полученные текстильные материалы с пленочным нанокомпозитным гидрогелевым покрытием могут найти применение в качестве перевязочных средств при лечении ран. Nanotechnologies using biopolymers are widely used in biomedical applications. In this work, nanocomposite hydrogels based on natural (chitosan, carboxymethylcellulose) and synthetic (polyvinyl alcohol) polymers with silver nanoparticles for application to a textile carrier have been developed. Carboxymethylcellulose dialdehyde and boric acid were used as crosslinking reagents in the creation of hydrogels. Physicochemical properties (sorption capacity in unilateral contact with the model medium, degree of swelling, vapor permeability, capillarity) of hydrogel coatings on a textile carrier, and the kinetics of the drugs release (lidocaine, dioxidine) included in the hydrogels were determined. It is shown that materials with a two-layer coating are characterized by higher sorption properties relative to saline and a longer release of drugs than materials with a single-layer coating. The release of drugs from the two-layer coatings occurs in two stages with a maximum release within two days. The obtained textile materials with a film nanocomposite hydrogel coating can be used as dressings in the treatment of wounds.

Fabrication and Characterization of Nanocomposite Hydrogel Based on Alginate/Nano-Hydroxyapatite Loaded with Linum usitatissimum Extract as a Bone Tissue Engineering Scaffold

In the current paper, we fabricated, characterized, and applied nanocomposite hydrogel based on alginate (Alg) and nano-hydroxyapatite (nHA) loaded with phenolic purified extracts from the aerial part of Linum usitatissimum (LOH) as the bone tissue engineering scaffold. nHA was synthesized based on the wet chemical technique/precipitation reaction and incorporated into Alg hydrogel as the filler via physical cross-linking. The characterizations (SEM, DLS, and Zeta potential) revealed that the synthesized nHA possess a plate-like shape with nanometric dimensions. The fabricated nanocomposite has a porous architecture with interconnected pores. The average pore size was in the range of 100–200 µm and the porosity range of 80–90%. The LOH release measurement showed that about 90% of the loaded drug was released within 12 h followed by a sustained release over 48 h. The in vitro assessments showed that the nanocomposite possesses significant antioxidant activity promoting bone regeneration. The hemolysis induction measurement showed that the nanocomposites were hemocompatible with negligible hemolysis induction. The cell viability/proliferation confirmed the biocompatibility of the nanocomposites, which induced proliferative effects in a dose-dependent manner. This study revealed the fabricated nanocomposites are bioactive and osteoactive applicable for bone tissue engineering applications.

Acupoint nanocomposite hydrogel for simulation of acupuncture and targeted delivery of triptolide against rheumatoid arthritis

Background Attenuating inflammatory response and relieving pain are two therapeutic therapeutical goals for rheumatoid arthritis (RA). Anti-inflammatory and analgesic drugs are often associated with many adverse effects due to nonspecific distribution. New drug delivery systems with practical targeting ability and other complementary strategies urgently need to be explored. To achieve this goal, an acupoint drug delivery system that can target deliver anti-inflammatory drugs and simulate acupuncture in relieving pain was constructed, which can co-deliver triptolide (TP) and 2-chloro-N (6)-cyclopentyl adenosine (CCPA). Results We have successfully demonstrated that acupoint nanocomposite hydrogel composed of TP-Human serum album nanoparticles (TP@HSA NPs) and CCPA could effectively treat RA. The result shows that CCPA-Gel can enhance analgesic effects specifically at the acupoint, while the mechanical and thermal pain threshold was 4.9 and 1.6 times compared with non-acupoint, respectively, and the nanocomposite gel further enhanced. Otherwise, the combination of acupoint and nanocomposite hydrogel exerted synergetic improvement of inflammation, bone erosion, and reduction of systemic toxicity. Furthermore, it could regulate inflammatory factors and restore the balance of Th17/Treg cells, which provided a novel and effective treatment strategy for RA. Interestingly, acupoint administration could improve the accumulation of the designed nanomedicine in arthritic paws (13.5% higher than those in non-acupoint at 48 h), which may explain the better therapeutic efficiency and low toxicity. Conclusion This novel therapeutic approach-acupoint nanocomposite hydrogel, builds a bridge between acupuncture and drugs which sheds light on the combination of traditional and modern medicine. Graphical Abstract