Synthesis and characterization of chitosan pyridyl imine palladium (CPIP) complex as green catalyst for organic transformations

Palladium Supported on Bioinspired Materials as Catalysts for C–C Coupling Reactions

In recent years, the immobilization of palladium nanoparticles on solid supports to prepare active and stable catalytic systems has been deeply investigated. Compared to inorganic materials, naturally occurring organic solids are inexpensive, available and abundant. Moreover, the surface of these solids is fully covered by chelating groups which can stabilize the metal nanoparticles. In the present review, we have focused our attention on natural biomaterials-supported metal catalysts applied to the formation of C–C bonds by Mizoroki–Heck, Suzuki–Miyaura and Sonogashira reactions. A systematic approach based on the nature of the organic matrix will be followed: (i) metal catalysts supported on cellulose; (ii) metal catalysts supported on starch; (iii) metal catalysts supported on pectin; (iv) metal catalysts supported on agarose; (v) metal catalysts supported on chitosan; (vi) metal catalysts supported on proteins and enzymes. We will emphasize the effective heterogeneity and recyclability of each catalyst, specifying which studies were carried out to evaluate these aspects.

Polydopamine Biomaterials for Skin Regeneration

Designing biomaterials capable of biomimicking wound healing and skin regeneration has been receiving increasing attention recently. Some biopolymers behave similarly to the extracellular matrix (ECM), supporting biointerfacial adhesion and intrinsic cellular interactions. Polydopamine (PDA) is a natural bioadhesive and bioactive polymer that endows high chemical versatility, making it an exciting candidate for a wide range of biomedical applications. Moreover, biomaterials based on PDA and its derivatives have near-infrared (NIR) absorption, excellent biocompatibility, intrinsic antioxidative activity, antibacterial activity, and cell affinity. PDA can regulate cell behavior by controlling signal transduction pathways. It governs the focal adhesion behavior of cells at the biomaterials interface. These features make melanin-like PDA a fascinating biomaterial for wound healing and skin regeneration. This paper overviews PDA-based biomaterials' synthesis, properties, and interactions with biological entities. Furthermore, the utilization of PDA nano- and microstructures as a constituent of wound-dressing formulations is highlighted.

Polylysine for skin regeneration: A review of recent advances and future perspectives

There have been several attempts to find promising biomaterials for skin regeneration, among which polylysine (a homopolypeptide) has shown benefits in the regeneration and treatment of skin disorders. This class of biomaterials has shown exceptional abilities due to their macromolecular structure. Polylysine-based biomaterials can be used as tissue engineering scaffolds for skin regeneration, and as drug carriers or even gene delivery vectors for the treatment of skin diseases. In addition, polylysine can play a preservative role in extending the lifetime of skin tissue by minimizing the appearance of photodamaged skin. Research on polylysine is growing today, opening new scenarios that expand the potential of these biomaterials from traditional treatments to a new era of tissue regeneration. This review aims to address the basic concepts, recent trends, and prospects of polylysine-based biomaterials for skin regeneration. Undoubtedly, this class of biomaterials needs further evaluations and explorations, and many critical questions have yet to be answered.

Human Organs-on-Chips: A Review of the State-of-the-Art, Current Prospects, and Future Challenges

New emerging technologies, remarkably miniaturized 3D organ models and microfluidics, enable simulation of the real in vitro microenvironment ex vivo more closely. There are many fascinating features of innovative organ-on-a-chip (OOC) technology, including the possibility of integrating semipermeable and/or stretchable membranes, creating continuous perfusion of fluids into microchannels and chambers (while maintaining laminar flow regime), embedding microdevices like microsensors, microstimulators, micro heaters, or different cell lines, along with other 3D cell culture technologies. OOC systems are designed to imitate the structure and function of human organs, ranging from breathing lungs to beating hearts. This technology is expected to be able to revolutionize cell biology studies, personalized precision medicine, drug development process, and cancer diagnosis/treatment. OOC systems can significantly reduce the cost associated with tedious drug development processes and the risk of adverse drug reactions in the body, which makes drug screening more effective. The review mainly focus on presenting an overview of the several previously developed OOC systems accompanied by subjects relevant to pharmacy-, cancer-, and placenta-on-a-chip. The challenging issues and opportunities related to these systems are discussed, along with a future perspective for this technology.

Development of a multifunctional system based on CoFe2O4@polyacrylic acid NPs conjugated to folic acid and loaded with doxorubicin for cancer theranostics

In this work, a multifunctional theranostic nanocomposite based on CoFe₂O₄@polyacrylic acid (PAA)-Folic Acid (FA) Doxorubicin (Dox)_loadNPs was designed for the multifunctional cancer treatment. Several techniques such as TEM, DLS,ζ-potential, vibrating sample magnetometer, XRD, and UV-Vis spectrophotometer were applied for investigating physicochemical properties of the nanosystem. The percentage of the loaded drug, loading efficiency,in vitrorelease (pH 5.4 and 7.4),invitroMRI measurements, and MTT assay (4T1 and 9A9 cell lines) were evaluated. Results showed that the percentage of loaded drug and loading efficiency was 53.33 ± 3.5 and 80.00 ± 5.3%, respectively, showing the system's high ability for Dox encapsulation. Release study showed that Dox loaded in the CoFe₂O₄@PAA-FA(Dox)_loadNPs released faster at pH 5.4 than pH 7.4.In vitro, MRI measurements confirmed that CoFe₂O₄@PAA NPs could be used as a contrast agent in MRI measurements withr₂ = 18.2 mM^-1s^-1. MTT assay demonstrated the biocompatibility of NPs, also showed a more efficient therapeutic effect for CoFe₂O₄@PAA-FA(Dox)_loadNPs than free Dox and CoFe₂O₄@PAA(Dox)_loadNPs.