No abstract

Physical interactions between glycol chitosan (GC) and silica nano-particles (SiNP) formed a hydrogel, with the features of injectability, skin adhesion and fibroblast encapsulation, which was used as a wound dressing to favor microvessel and hair follicle growth in skin defects.

Doxorubicin forms fibril-like aggregates in phosphate buffer and complexes with poly-l-lysine and cholate-grafted poly-l-lysine.

Polymeric micelles with combinatorial targeting ability for cancer cells was achieved by co-assembly of cRGD-PEO-b-PCL and tumor pHe sensitive PEG-DOX.

Keratin graft PHPMA copolymers were successfully synthesized and can be used as drug carriers with physiological stimuli responsive properties.

No abstract

Herein we report a facile route for the preparation of surface patterned dynamic hydrogel films, which are not only a matrix to encapsulate one type of cell in 3D but also a substrate to support aligned aggregates of magnetic silica rods to adhere another type of cell in 2D. This enables the composite hydrogel films to be flexible scaffolds for engineering multi-cellular tissues.Chemical cues and topography of a scaffold are able to affect cell behaviour and hence the quality of tissue regeneration. 1-4 For example, cell-growth direction, such as the alignment of cells in vessel endothelium, is recognized as a key issue in controlling the structure and composition of the particular tissue. 5,6 Thus the construction of extracellular substrates is of great interest to render the engineering of an oriented cell layer. Many approaches have been developed for the fabrication of a surface with bril like pattern in order to regulate the orientation of cells during their proliferation. 7-12 However, in most of the microfabrications, the substrate for supporting the patterned surface has no additional bio-function rather than providing mechanical properties. Natural tissues are normally multi-cellular systems of two or more types of cell. Therefore in recent years, hierarchical structured double-layered scaffolds were developed, 13 for example by electrospun technique, which contain a top layer formed by aligned bres and a bottom matrix by randomly packed bres for the co-culture of two cell lines, and thereby duplicate the architecture of native tissue like the peripheral nerve. 6 Nevertheless, it is still a challenge to develop exible scaffolds for simultaneously control growth of different cells.Hydrogel is known as an ideal extracellular matrix (ECM) for culturing cell in three dimensions (3D cell culture). 3,14,15 The so nature of hydrogel can more favourably mimic the property of so tissues. Besides, hydrogel has the capacity of incorporation of bioactives, such as growth factors, to inuence the embryonic development, proliferation and even the differentiation of the encapsulated cells. [16][17][18] Hydrogel for cell co-culture was also reported. 19-21 Bi-layered and multilayered bulk hydrogels have been synthesized to mediate the formation of distinctive structure of osteochondral tissue and articular cartilage. 22,23 However, in some cases it requires the proliferation of cell in 2D and 3D concurrently instead of a 3D/3D co-culture, such as for the regeneration of tissues containing endothelial system. Recently, the modication of hydrogel surface with celladhesive patterns for directional 2D culture has been documented in literatures. 7,24-26 Nevertheless, the fabrication involves organic solvent or other toxic additives. Therefore cells must be seeded aer the fabrication and thus can no longer be entrapped inside the gel substrate and proliferated in 3D.In previous work, we developed in situ forming hydrogel based on glycol chitosan (GC) and benzaldehyde capped poly (ethylene oxide) derivatives (OHC-PEO-C...

The platelet-shaped Janus nanocages with a mesoporous silica shell are prepared. PEG moiety onto the exterior surface is responsible for good dispersity in water. The graphene sheet inside the cavity is responsible for hydrophobic performance to selectively capture hydrophobic species, and photothermal effect by NIR irradiation. As a biocompatible DOX-loaded Janus platelet delivery, HeLa cell cytotoxicity is greatly enhanced under NIR irradiation. There exists a synergetic effect between the chemotherapy and photothermal therapy.