To improve the mechanical properties of bone tissue and achieve the desired bone tissue regeneration for orthopedic surgery, newly designed hydroxyapatite/polyurethane (HA/PU) porous scaffolds were developed via in situ polymerization. The results showed that the molecular modification of PU soft segments by glyceride of castor oil (GCO) can increase the scaffold compressive strength by 48% and the elastic modulus by 96%. When nano-HA (n-HA) particles were incorporated into the GCO-PU matrix, the compressive strength and elastic modulus further increased by 49 and 74%, from 2.91 to 4.34 MPa and from 95 to 165.36 MPa, respectively. The n-HA particles with fine dispersity not only improved the interface bonding with the GCO-PU matrix but also provided effective bioactivity for bonding with bone tissue. The hierarchical structure and mechanical quality of the n-HA/GCO-PU composite scaffold were determined to be appropriate for the growth of cells and the regeneration of bony tissues, demonstrating promising prospects for bone repair and regeneration.

Hydrogel beads based on the husk of agarwood fruit (HAF)/sodium alginate (SA), and based on the HAF/chitosan (CS) were developed for the removal of the dyes, crystal violet (CV) and reactive blue 4 (RB4), in aqueous solutions, respectively. The effects of the initial pH (2–10) of the dye solution, the adsorbent dosage (0.5–3.5 g/L), and contact time (0–540 min) were investigated in a batch system. The dynamic adsorption behavior of CV and RB4 can be represented well by the pseudo-second-order model and pseudo-first-order model, respectively. In addition, the adsorption isotherm data can be explained by the Langmuir isotherm model. Both hydrogel beads have acceptable adsorption selectivity and reusability for the study of selective adsorption and regeneration. Based on the effectiveness, selectivity, and reusability of these hydrogel beads, they can be treated as potential adsorbents for the removal of dyes in aqueous solutions.

The n-HA/CS microspheres exhibit good properties while supporting cell growth, thus acting as a promising injectable matrix for bone tissue engineering.

Redesigned multifunctional biopolymers represent a novel building bridge for interdisciplinary collaborations in biomaterials development. We prepared fluorescein-grafted polyurethane scaffolds (PU-C1, PU-C5, and PU-B1) to meet both clinical needs and biological safety evaluations, using different contents of calcein and different synthesis procedures for potential biomedical tracing. X-ray diffraction, infrared, X-ray photoelectron spectroscopy, nuclear magnetic resonance, scanning electron microscopy, and light microscopy were used to analyze the composition and structure of polyurethanes, as well as to observe their morphology with and without biomarkers. Fluorescence spectrophotometer and fluorescence microscopy were used to detect the fluorescence characteristics. The results showed that the grafting of calcein significantly affected the chemical structure and fluorescence sensitivities of copolymers. When compared to calcein, which was added before synthesis (PU-C1), the marker that was added during the extender process (PU-B1) presented higher fluorescence efficiency. Both PU-C5 and PU-B1 exhibited strong fluorescent response and good cytocompatibility in vitro and in vivo, with no interference from the autofluorescence of tissues after 4 weeks of implantation. The fluorescence-marked material can be used to continuously and noninvasively monitor the dynamic changes in polymers, which provides a way to clearly trace the material or to distinguish between the material and tissue in vivo.