Electrosprayed porous microspheres for the removal of endocrine disruptors

Bacterial infection microenvironment-responsive porous microspheres by microfluidics for promoting anti-infective therapy

The overuse of antibiotics for treating bacterial infection has caused severe bacterial resistance and become a public health threat worldwide. It is desired to develop novel antibiotic delivery systems as efficient antibacterial strategies for promoting anti-infective therapy. Herein, the AgNPs-loaded N-[(2-hydroxy-3-trimethyl ammonium) propyl] chitosan (HTCC)/hyaluronic acid (HA) porous microspheres (HHPMs) by microfluidics have been developed as novel bacterial infection microenvironment (IME)-responsive antibiotic delivery systems for promoting antimicrobial therapy. The release of AgNPs can respond explicitly to the IME with acidic pH values and relatively high hyaluronidase concentration. The unique porous structures of HHPMs can effectively facilitate the capture and enrichment of bacteria, thus exerting synergistic antibacterial effects, which can be more efficient in instant bacteria inhibiting and killing. The excellent biocompatibility of HHPMs is revealed by investigating their hemolytic activity and cytotoxicity. In vivo assays demonstrate that the fabricated AgNPs-loaded HHPMs can effectively resist bacterial infection and promote wound healing and tissue regeneration at infected wound sites by inhibition of the bacterial survival. This work indicates that fabricated HHPMs are ideal bacterial infection microenvironment-responsive materials for antibiotic delivery and show great promises for promoting anti-infective therapy in clinics.

Preparation of fluorinated PCL porous microspheres and a super-hydrophobic coating on fabrics via electrospraying

In this study, fluorinated polycaprolactone (PCL) block polymers with different fluorine contents were synthesized via atom transfer radical polymerization (ATRP). An electrospraying technique was used to prepare fluorinated PCL microspheres with different microstructures. In contrast to the golf ball shape of unmodified PCL microspheres displaying porous pits on the surface, block polymer PCL-PTFOA(2 h) and PCL-PTFOA(6 h) microsphere surfaces displayed regular honeycomb-like pore structures. Thermally induced and evaporation-induced phase separations are proposed as the main mechanisms involved in the formation of the porous microstructures. The micro-phase separation between the two blocks of the fluorinated PCL copolymer is another factor that promoted the uniform collapse on the microsphere surface and the formation of its rugged wall. The surface roughness of the porous microspheres significantly improved their hydrophobicity, generating coating contact angles on aluminium foil substrates that measured as high as 162.4 ± 1.5°, which revealed that the surfaces were super-hydrophobic. Lastly, cotton fabric was directly coated with the fluorinated polymer microspheres via electrospraying, resulting in super-hydrophobic surfaces and CAs reaching 160.0 ± 1.3°. The results demonstrate that electrospraying is a simple, innovative and cost-effective method for preparing polymer microspheres with controllable microstructures for fabric coating applications.

PES magnetic microspheres: preparation and performance for the removal of endocrine disruptor-BPA

PES magnetic microspheres were prepared via electrospraying and in situ reaction, and they were applied for the removal of BPA.

Electrospray loading and release of hydrophobic gramicidin in polyester microparticles

Gramicidin, a pentadecapeptide with well-known antimicrobial properties and recently identified therapeutic activity against different carcinomas, has been loaded by electrospraying in biodegradable and biocompatible poly(tetramethylene succinate).

An overview of inverted colloidal crystal systems for tissue engineering

Scaffolding is at the heart of tissue engineering but the number of techniques available for turning biomaterials into scaffolds displaying the features required for a tissue engineering application is somewhat limited. Inverted colloidal crystals (ICCs) are inverse replicas of an ordered array of monodisperse colloidal particles, which organize themselves in packed long-range crystals. The literature on ICC systems has grown enormously in the past 20 years, driven by the need to find organized macroporous structures. Although replicating the structure of packed colloidal crystals (CCs) into solid structures has produced a wide range of advanced materials (e.g., photonic crystals, catalysts, and membranes) only in recent years have ICCs been evaluated as devices for medical/pharmaceutical and tissue engineering applications. The geometry, size, pore density, and interconnectivity are features of the scaffold that strongly affect the cell environment with consequences on cell adhesion, proliferation, and differentiation. ICC scaffolds are highly geometrically ordered structures with increased porosity and connectivity, which enhances oxygen and nutrient diffusion, providing optimum cellular development. In comparison to other types of scaffolds, ICCs have three major unique features: the isotropic three-dimensional environment, comprising highly uniform and size-controllable pores, and the presence of windows connecting adjacent pores. Thus far, this is the only technique that guarantees these features with a long-range order, between a few nanometers and thousands of micrometers. In this review, we present the current development status of ICC scaffolds for tissue engineering applications.