Magnetic targeting cobalt nanowire-based multifunctional therapeutic system for anticancer treatment and angiogenesis.

In order to improve the anticancer therapeutic efficacy and postoperative recovery efficacy, the novel anticancer therapeutic system should have the ability to promote angiogenesis after anticancer therapy besides the excellent anticancer therapeutic efficacy. We present herein a magnetic targeting multifunctional anticancer therapeutic system based on cobalt nanowires (CoNWs) for anticancer therapy and angiogenesis. Magnetic characterization shows that the CoNWs can be concentrated in desired locations under the external magnetic field, which is favorable for anticancer target therapy. Besides, drug loading/release characterization reveals that the CoNWs interact with doxorubicin (DOX) by electrostatic interaction, and accordingly form a composite which can release DOX with temperature increase under near-infrared light (NIR) treatment. And anticancer test reveals that the nanowires loaded with the DOX (CoNWs-DOX) can produce an effective chemo-photothermal synergistic therapeutic effect against murine breast cancer cell lines (4T1) and human osteosarcoma cell lines (MG63) under NIR treatment. Furthermore, angiogenesis assessment reveals that the released cobalt ion from the nanowires can significantly enhance the angiogenesis efficacy after cancer treatment. These results suggest that the constructed anticancer therapeutic system provides a promising multifunctional platform for cancer treatment and postoperative recovery.

Multifunctional Surface with Enhanced Angiogenesis for Improving Long-Term Osteogenic Fixation of Poly(ether ether ketone) Implants.

Poly(ether ether ketone) (PEEK) is a biocompatible polymer, but the lack of angiogenesis makes the long-term osteogenic fixation of PEEK implants challenging, which has hampered their wider application in orthopedics. Herein, we develop a multifunctional micro-/nanostructured surface presenting hydroxyapatite (HA) nanoflowers and nickel hydroxide (Ni(OH)2) nanoparticles on PEEK implants (sPEEK-Ni-HA) to tackle the problem. The results show that the reasonable release of Ni2+ from sPEEK-Ni-HA significantly facilitates the migration, tube formation, and angiogenic gene expression of human umbilical vein endothelial cells (HUVECs). In addition to angiogenesis, the sPEEK-Ni-HA displays enhanced cytocompatibility and osteogenicity in terms of cell proliferation, spreading, alkaline phosphatase activity, matrix mineralization, and osteogenesis-related gene secretion, exceeding pure and other multifunctional sPEEK samples. Importantly, in vivo evaluations employing a rabbit femoral condyle implantation model confirm that such dual decoration of Ni elements and HA nanoflowers boosts bone remodeling/osseointegration, which dramatically promotes the in vivo osteogenic fixation of implants. Therefore, this work not only sheds light on the significance of angiogenesis on the osteogenic fixation of an implant but also presents a facile strategy to empower bioinert PEEK with a well-orchestrated feature of angiogenesis and osteogenesis.

Dual Physically Cross-Linked κ-Carrageenan-Based Double Network Hydrogels with Superior Self-Healing Performance for Biomedical Application.

Chemically linked double network (DN) hydrogels display extraordinary mechanical attributes but mostly suffer from poor self-healing property and unsatisfactory biocompatibility due to the irreversible breaks in their chemical-linked networks and the use of toxic chemical cross-linking agents. To address these limitations, we developed a novel κ-carrageenan/polyacrylamide (KC/PAM) DN hydrogel through a dual physical-cross-linking strategy, with the ductile, hydrophobically associated PAM being the first network, and the rigid potassium ion (K+) cross-linked KC being the second network. The dual physically cross-linked DN (DPC-DN) hydrogels with optimized KC concentration exhibit excellent fracture tensile stress (1320 ± 46 kPa) and toughness (fracture energy: 6900 ± 280 kJ/m3), comparable to those fully chemically linked DN hydrogels and physically chemically cross-linked hybrid DN hydrogels. Moreover, because of their unique dual physical-cross-linking structures, the KC/PAM hydrogels also demonstrated rapid self-recovery, remarkable notch-insensitivity, self-healing capability, as well as excellent cytocompatibility toward stem cells. Accordingly, this work presents a new strategy toward fabricating self-repairing DPC-DN hydrogels with outstanding mechanical behaviors and biocompatibility. The new type of DN hydrogels demonstrates strong potentiality in many challenging biomedical applications such as artificial diaphragm, tendon, and cartilage.

Graphene-Oxide-Decorated Microporous Polyetheretherketone with Superior Antibacterial Capability and In Vitro Osteogenesis for Orthopedic Implant.

Due to its similar elastic modulus of human bones, polyetheretherketone (PEEK) has been considered as an excellent cytocompatible material. However, the bioinertness, poor osteoconduction, and weak antibacterial activity of PEEK limit its wide applications in clinics. In this study, a facile strategy is developed to prepare graphene oxide (GO) modified sulfonated polyetheretherketone (SPEEK) (GO-SPEEK) through a simple dip-coating method. After detailed characterization, it is found that the GO closely deposits on the surface of PEEK, which is attributed to the π-π stacking interaction between PEEK and GO. Antibacterial tests reveal that the GO-SPEEK exhibits excellent suppression toward Escherichia coli. In vitro cell attachment, growth, differentiation, alkaline phosphatase activity, quantitative real-time polymerase chain reaction analyses, and calcium mineral deposition all illustrate that the GO-SPEEK substrate can significantly accelerate the proliferation and osteogenic differentiation of osteoblast-like MG-63 cells compared with those on PEEK and SPEEK groups. These results suggest that the GO-SPEEK has an improved antibacterial activity and cytocompatibility in vitro, showing that the developed GO-SPEEK has a great potential as the bioactive implant material in bone tissue engineering.