pH-Sensitive Dextran-Based Micelles from Copper-Free Click Reaction for Antitumor Drug Delivery

A Triterpene-Based bioactive drug delivery system for combined chemotherapy of liver cancer

Carrier materials always account for the majority particularly in nanosized formulations, which are administrated along with the active ingredient part might result in metabolism related toxicity. The usage of bioactive excipients could not only reduce the sided effect but also provide additional therapeutic effects. In the present study, a triterpene based micellar drug delivery system was developed using a bioactive solanesol derivative. Solanesylamine was prepared firstly followed by conjugating with poly (ethylene glycol) using maleic acid amide linkage. The amphiphilic drug carrier PEGylated (2-propyl-3-methylmaleic acid)-block-solanesol amine (mPEG-CDM-NH-SOL) could be formed into micelles and loaded with doxorubicin (DOX) inside. The micelles were about 112 nm in size and the drug loading content was about 5.97 wt%. An acid triggered drug release behavior was obviously observed for the DOX loaded pH-sensitive micelle mPEG-CDM-NH-SOL-DOX. While not for DOX-loaded micelles without pH-sensitivity (mPEG-NHS-NH-SOL). CCK8 assay showed that the micelles of PEGylated solanesylamines exhibited certain inhibitory effect on tumor cells at high concentration and the pH sensitive ones seemed more toxic. In vivo studies showed that the pH sensitive mPEG-CDM-NH-SOL-DOX had a superior anti-tumor effect, indicating its great potential in cancer treatment.

pH-Responsive Micellar Nanoparticles for the Delivery of a Self-Amplifying ROS-Activatable Prodrug

The objective of this study is to enhance the therapeutic efficacy of the anticancer drug, camptothecin (CPT) via a nanoparticle (NP) formulation using a novel amphiphilic biopolymer. We have designed a dimeric prodrug of CPT with the ability to self-amplify and respond to reactive oxygen species (ROS). For this, we incorporated the intracellular ROS generator cinnamaldehyde into a ROS-cleavable thioacetal (TA) linker to obtain the dimeric prodrug of CPT (DCPT(TA)). For its efficient NP delivery, a pH-responsive block copolymer of acetalated dextran and poly(2-ethyl-2-oxazoline) (AcDex-b-PEOz) was synthesized. The amphiphilic feature of the block copolymer enables its self-assembly into micellar NPs and results in high prodrug loading capacity and a rapid release of the prodrug under acidic conditions. Upon cellular uptake by HeLa cells, DCPT(TA)-loaded micellar NPs induce intracellular ROS generation, resulting in accelerated prodrug activation and enhanced cytotoxicity. These results indicate that this system holds significant potential as an effective prodrug delivery strategy in anticancer treatment.

Exploring the Application of Micellar Drug Delivery Systems in Cancer Nanomedicine

Various formulations of polymeric micelles, tiny spherical structures made of polymeric materials, are currently being investigated in preclinical and clinical settings for their potential as nanomedicines. They target specific tissues and prolong circulation in the body, making them promising cancer treatment options. This review focuses on the different types of polymeric materials available to synthesize micelles, as well as the different ways that micelles can be tailored to be responsive to different stimuli. The selection of stimuli-sensitive polymers used in micelle preparation is based on the specific conditions found in the tumor microenvironment. Additionally, clinical trends in using micelles to treat cancer are presented, including what happens to micelles after they are administered. Finally, various cancer drug delivery applications involving micelles are discussed along with their regulatory aspects and future outlooks. As part of this discussion, we will examine current research and development in this field. The challenges and barriers they may have to overcome before they can be widely adopted in clinics will also be discussed.

The State of the Art of Natural Polymer Functionalized Fe3O4 Magnetic Nanoparticle Composites for Drug Delivery Applications: A Review

Natural polymers have received a great deal of interest for their potential use in the encapsulation and transportation of pharmaceuticals and other bioactive compounds for disease treatment. In this perspective, the drug delivery systems (DDS) constructed by representative natural polymers from animals (gelatin and hyaluronic acid), plants (pectin and starch), and microbes (Xanthan gum and Dextran) are provided. In order to enhance the efficiency of polymers in DDS by delivering the medicine to the right location, reducing the medication's adverse effects on neighboring organs or tissues, and controlling the medication's release to stop the cycle of over- and under-dosing, the incorporation of Fe3O4 magnetic nanoparticles with the polymers has engaged the most consideration due to their rare characteristics, such as easy separation, superparamagnetism, and high surface area. This review is designed to report the recent progress of natural polymeric Fe3O4 magnetic nanoparticles in drug delivery applications, based on different polymers' origins.

Recent Reports on Polysaccharide-Based Materials for Drug Delivery

Polysaccharides constitute one of the most important families of biopolymers. Natural polysaccharide-based drug delivery systems are of constant interest to the scientific community due to their unique properties: biocompatibility, non-toxicity, biodegradability, and high availability. These promising biomaterials protect sensitive active agents and provide their controlled release in targeted sites. The application of natural polysaccharides as drug delivery systems is also intensively developed by Polish scientists. The present review focuses on case studies from the last few years authored or co-authored by research centers in Poland. A particular emphasis was placed on the diversity of the formulations in terms of the active substance carried, the drug delivery route, the composition of the material, and its preparation method.

On-Surface Azide-Alkyne Cycloaddition Reaction: Does It Click with Ruthenium Catalysts?

Owing to its simplicity, selectivity, high yield, and the absence of byproducts, the "click" azide-alkyne reaction is widely used in many areas. The reaction is usually catalyzed by copper(I), which selectively produces the 1,4-disubstituted 1,2,3-triazole regioisomer. Ruthenium-based catalysts were later developed to selectively produce the opposite regioselectivity─the 1,5-disubstituted 1,2,3-triazole isomer. Ruthenium-based catalysis, however, remains only tested for click reactions in solution, and the suitability of ruthenium catalysts for surface-based click reactions remains unknown. Also unknown are the electrical properties of the 1,4- and 1,5-regioisomers, and to measure them, both isomers need to be assembled on the electrode surface. Here, we test whether ruthenium catalysts can be used to catalyze surface azide-alkyne reactions to produce 1,5-disubstituted 1,2,3-triazole, and compare their electrochemical properties, in terms of surface coverages and electron transfer kinetics, to those of the compound formed by copper catalysis, 1,4-disubstituted 1,2,3-triazole isomer. Results show that ruthenium(II) complexes catalyze the click reaction on surfaces yielding the 1,5-disubstituted isomer, but the rate of the reaction is remarkably slower than that of the copper-catalyzed reaction, and this is related to the size of the catalyst involved as an intermediate in the reaction. The electron transfer rate constant (ket) for the ruthenium-catalyzed reaction is 30% of that measured for the copper-catalyzed 1,4-isomer. The lower conductivity of the 1,5-isomer is confirmed by performing nonequilibrium Green's function computations on relevant model systems. These findings demonstrate the feasibility of ruthenium-based catalysis of surface click reactions and point toward an electrical method for detecting the isomers of click reactions.

Supramolecular Vector/Drug Coassemblies of Polyglycerol Dendrons and Rutin Enhance the pH Response

A coassembly strategy for a supramolecular vector/drug was proposed with a biocompatible ternary dodecyl-bi(third-generation polyglycerol (PG) dendrons) (C₁₂-(G3)₂) amphiphile, dodecyl sulfobetaine (SB3-12) surfactant, and poorly water-soluble drug rutin. C₁₂-(G3)₂ and rutin will mutually enhance their pH response by protonation and deprotonation of dendritic PG and rutin's ionization as the pH changes from the acidic gastric lumen to the weakly alkaline intestine. SB3-12 may increase the payload and bring about sustained release for rutin by intermolecular interactions. Self-assembling behaviors of C₁₂-(G3)₂, SB3-12, sodium dodecyl sulfate (SDS), and dodecyl trimethylammonium bromide (DTAB) and their hybrids with rutin were characterized by UV-vis spectroscopy, a fluorescence probe, and ¹H NMR. UV-vis and ¹H NMR were used to identify the position and orientation of rutin in the vectors. The functions of the vector/drug were confirmed by measuring the solubility and in vitro release of rutin. The ternary coassembling vector/drug easily imparted functions of pH-responsive and sustained release without complex synthetic processes. The nanocaves framed by PG dendrons in the micelles provide pH-responsive compartments for rutin and SB3-12 in the supramolecular vector/drug anchors that accommodate rutin by weak interactions. The finely matched supramolecular vector/drug coassemblies exhibit the pH-responsive function for a potential application in the treatment of inflammatory bowel disease.