Continuous preparation of strong and tough PVA nanocomposite fibers by mechanical stretching-assisted salting-out treatment

Polymer composite fibers with superior properties such as excellent combined strength and toughness and biocompatibility can be used in high-tech applications of braided protective devices and smart wearable,however the research of high-performance polymer composite fiber remains in the infant stage.Here we present a strategy to produce strong and tough anisotropic polymer nanocomposite fibers with orientedly aligned salt rods using mechanical stretching-assisted salting-out treatment.The prepared nanocomposite fibers have a tensile strength of up to 786±2.7 MPa and an elongation at break of 81%,and the anisotropic fibers exhibit good transmission of mechanical vibration in the longitudinal direction with high resolution.During the fabrication process,the salt builds up into oriented rods during the directional salting process,and the polymer is confined to the 150 nm domain between the rods after the solvent is completely evaporated,giving the nanocomposite fibers superior mechanical properties.The presented strategy can be applied to the continuous mass production of nanocomposite fibers and is also generalizable to other polymer nanocomposites,which could extend the applicability of nanocomposite fibers to conditions involving more demanding mechanical loading and mechanical vibration transmission.

Development of a concentration-controlled sequential nanoprecipitation for making lipid nanoparticles with high drug loading

Lipid-based nanostructures have garnered considerable interests over the last two decades,and have achieved tremendous clinical success including thefirst clinical approval of a liposome(Doxil)for cancer therapy in 1995 and the recent COVID-19 mRNA lipid nanoparticle vaccines.Compared to liposomes which have a lipid bilayer surrounding an aqueous core,lipid nanoparticles with a particle structure have several attractive advantages for encapsulating poorly water-soluble drugs such as better stability due to the particle structure,high drug encapsulation efficiency because of a pre-or co-drug-loading strategy.While many studies have reported the synthesis of lipid nanoparticles for hydrophobic drug encapsulation,the pre-cise control of drug loading and encapsulation efficiency remains a significant challenge.This work reports a new concentration-controlled nanoprecipitation plat-form technology for fabricating lipid nanoparticles with tunable drug loading up to 70 wt%.This method is applicable for encapsulating a wide range of drugs from very hydrophobic to slightly hydrophilic.Using this facile method,nanoparticles with tunable drug loading exhibited excellent properties such as small particle size,narrow size distribution,good particle stability,showing great promise for future drug delivery applications.

Phase separation-induced nanoprecipitation for making polymer nanoparticles with high drug loading Special Collection:Distinguished Australian Researchers

Increasing drug loading remains a critical challenge in the development and translation of nanomedicine.High drug-loading nanoparticles have demonstrated unique advantages such as less carrier material used,better-controlled drug release,and improved efficacy and safety.Herein,we report a simple and efficient salt concentration screening method for making polymer nanoparticles with exceptionally high drug loading(up to 66.5 wt%)based on phase separation-induced nanoprecipitation.Upon addition of salt,phase separation occurs in a miscible solvent-water solution delaying the precipitation time of drugs and polymers to different extents,facilitating their co-precipitation thus the formation of high drug-loading nanoparticles with high encapsulation efficiency(>90%)and excellent stability(>1 month).This technology is versatile and easy to be adapted to various hydrophobic drugs,different polymers,and solvents.This salt-induced nanoprecipitation strategy offers a novel approach to fabricating polymer nanoparticles with tunable drug loading,and opens great potentials for future nanomedicines.

Nanoemulsions for drug delivery

Emulsions are liquid-liquid dispersions with one liquid phase dispersed in the other liquid phase as small droplets.Nanoemulsions are nano-sized emulsions with sizes ranging from tens to hundreds of nanometers,and have great potential applications in pharmaceutics,foods and cosmetics due to their attractive properties,such as small sizes,high surface area per unit volume,improved dispersion of active hydrophobic components and enhanced absorption.The article provides an overview of nanoemulsions for drug delivery,starting with an introduction of emulsion types,nanoemulsion preparation and nanoemulsion stability.Surfactants play critical roles in producing and stabilizing nanoemulsions.Different types of surfactants are summarized including small molecule surfactants,particle surfactants,phospholipids,peptide and protein surfactants.Then the applications of nanoemulsions as nanomedicine in drug delivery are presented.Finally,clinical applications of nanoemulsions are discussed.

Use of copper-cysteamine nanoparticles to simultaneously enable radiotherapy,oxidative therapy and immunotherapy for melanoma treatment

Dear Editor,Melanoma,squamous cell carcinoma(SCC),and basal cell carcinoma(BCC)are three major types of skin cancer.Among them,melanoma is the most severe form and accounts for~4%of all newly diagnosed cancers annually in the United States.It is estimated that approximately 9500 people are diagnosed with skin cancer every day,and more than 1 million Americans are living with melanoma.Melanoma treatment is still a major challenge in the clinic.Photodynamic therapy(PDT)is composed of targeted ablation and immune activation,is less invasive than other therapies and has been widely used in the treatment of various cancers.