Au-poly(lactic-co-glycolic) acid complex nanoparticles as ultrasound contrast agents: Preparation, characterization and in�vitro study

Gold-iron oxide (Au/Fe3O4) magnetic nanoparticles as the nanoplatform for binding of bioactive molecules through self-assembly

Nanomedicine plays a crucial role in the development of next-generation therapies. The use of nanoparticles as drug delivery platforms has become a major area of research in nanotechnology. To be effective, these nanoparticles must interact with desired drug molecules and release them at targeted sites. The design of these “nanoplatforms” typically includes a functional core, an organic coating with functional groups for drug binding, and the drugs or bioactive molecules themselves. However, by exploiting the coordination chemistry between organic molecules and transition metal centers, the self-assembly of drugs onto the nanoplatform surfaces can bypass the need for an organic coating, simplifying the materials synthesis process. In this perspective, we use gold-iron oxide nanoplatforms as examples and outline the prospects and challenges of using self-assembly to prepare drug-nanoparticle constructs. Through a case study on the binding of insulin on Au-dotted Fe3O4 nanoparticles, we demonstrate how a self-assembly system can be developed. This method can also be adapted to other combinations of transition metals, with the potential for scaling up. Furthermore, the self-assembly method can also be considered as a greener alternative to traditional methods, reducing the use of chemicals and solvents. In light of the current climate of environmental awareness, this shift towards sustainability in the pharmaceutical industry would be welcomed.

Biomimetic PLGA Microbubbles Coated with Platelet Membranes for Early Detection of Myocardial Ischaemia-Reperfusion Injury

Early diagnosis of myocardial ischaemia-reperfusion (MI/R) injury is important for protecting the myocardium and improving patient prognoses. Fortunately, the platelet membrane possesses the ability to target the region of MI/R injury. Therefore, we hypothesized that platelet membrane-coated particles (PMPs) could be used to detect early MI/R injury by ultrasound imaging. We designed PMPs with a porous polylactic-co-glycolic acid (PLGA) core coated with a platelet membrane shell. Red blood cell membrane-coated particles (RMPs) were fabricated as controls. Transmission electron microscopy (TEM) and fluorescence microscopy were applied to confirm the membrane coatings of the PMPs and RMPs. In vitro imaging of the PMPs and RMPs was verified. Moreover, binding experiments were designed to examine the targeting ability of the PMPs. Finally, we assessed the signal intensity of the adherent PMPs in the risk area and remote area by ultrasound imaging based on an MI/R rat model. The platelet membrane equipped the PMPs with an accurate targeting ability. Compared with RMPs, PMPs showed significantly more adhesion to human umbilical vein endothelial cells and collagen IV in vitro. Both PMPs and RMPs exhibited good enhancement ability in vitro and in vivo. Furthermore, the signal intensity of PMPs in the risk area was significantly higher than that in remote areas. These results were further validated by an immunofluorescence assay and ex vivo fluorescence imaging. In summary, ultrasound imaging with PMPs can detect early MI/R injury in a noninvasive manner.

Biosynthesis, characterization, and evaluation of bioactivities of leaf extract-mediated biocompatible gold nanoparticles from Alternanthera bettzickiana

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The gold nanoparticles (AuNPs) were synthesised using leaf extract of Alternanthera bettzickiana.

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The Au NPs were characterized using UV-vis, XRD, FTIR, SEM, TEM and Zeta potential.

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A simple, quick and reproducible method for the environmentally friendly synthesis of Au NPs without the need for expensive reducing agents.

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The cytotoxic effect of the green synthesized Au NPs against A549 human lung cancer cell lines provided a vigorous evidence of anticancer activity of Au NPs.

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The toxicity study of the green synthesized Au NPs on Danio rerio (Zebra fish) embryo was evaluated

The objective of the study was to synthesize gold nanoparticles (Au NPs) using leaf extract of Alternanthera bettzickiana (A. bettzickiana). The biosynthesized Au NPs were characterized using UV–vis spectroscopy, X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy dispersive X-ray analysis (EDX), Zeta potential and Transmission electron microscopy (TEM). Morphologically, the Au NPs showed spherical shaped structures. Size distribution of Au NPs calculated using Scherrer’s formula, showed an average size of 80–120 nm. Au NPs were studied for invitro anti-bacterial and cytotoxic activities. Au NPs exhibited significant anti-microbial activity against Bacillu subtilis, Staphylococcus aureus, Salmonella typhi, Pseudomonas aeroginosa, Micrococcus luteus, and Enterobacter aerogenes by agar well diffusion method. The cytotoxic effect of the biogenic synthesized Au NPs against A549 human lung cancer cell lines provided a vigorous evidence of anticancer activity of Au NPs. Further, the toxicity study of the green synthesized Au NPs on Danio rerio (Zebra fish) embryo was evaluated. This study reports that colloidal Au NPs can be synthesized by simple, non-hazardous methods and that bio-synthesized Au NPs have significant therapeutic properties.