Polyelectrolyte complex templated synthesis of monodisperse, sub-100 nm porous silica nanoparticles for cancer targeted and stimuli-responsive drug delivery

Effect of Degree of Substitution and Polymer Ratio on the Structure of Chitosan: Carboxymethyl Starch (Bio)Polyelectrolyte Complexes

In this work, three carboxymethyl starches (CMS) were obtained by the two-step reaction process of carboxymethylation with different degrees of substitution (0.16, 0.33, and 0.36). From these samples, (bio)polyelectrolyte complexes ((bio)PECs) were obtained with chitosan (Chit) by the mixing of individual solutions of polymers (0.25 wt.%) at different volume ratios. The effect of the biopolymer and ionized groups of z ratios, pH, and degree of substitution of CMS in the formation of PEC were evaluated by turbidimetry and dynamic light scattering. The results showed that increasing the amount of CMS samples (ratio of z) led to an increase in the efficiency of the formation of (bio)PEC using CMS with a high DS value. Using the turbidimetry method for the chitosan and CMS mixtures, it was observed that the formation of (bio)PEC is divided into four transition zones delimited by pH transition points, and the stoichiometric complexation (z = 1) is achieved at a pH that displayed morphological changes "pHmorph", which is a single point for Chit:CMS 1, and for Chit:CMS 2 and Chit:CMS 3, this is a range of 4.9-6.4 and 4.3-6.4, respectively. Analysis of the structural properties of the structures of (bio)PECs by dynamic light scattering was characterized by monomodal distribution, and the main observed effect was associated with an increase in the value of Davg with an increase in the ratio of Chit:CMS.

Harnessing polyelectrolyte complexes for precision cancer targeting: a comprehensive review

Polyelectrolytes represent a unique class of polymers abundant in ionizable functional groups. In a solution, ionized polyelectrolytes can intricately bond with oppositely charged counterparts, giving rise to a fascinating phenomenon known as a polyelectrolyte complex. These complexes arise from the interaction between oppositely charged entities, such as polymers, drugs, and combinations thereof. The polyelectrolyte complexes are highly appealing in cancer management, play an indispensable role in chemotherapy, crafting biodegradable, biocompatible 3D membranes, microcapsules, and nano-sized formulations. These versatile complexes are pivotal in designing controlled and targeted release drug delivery systems. The present review emphasizes on classification of polyelectrolyte complex along with their formation mechanisms. This review comprehensively explores the applications of polyelectrolyte complex, highlighting their efficacy in targeted drug delivery strategies for combating different forms of cancer. The innovative use of polyelectrolyte complex presents a potential breakthrough in cancer therapeutics, demonstrating their role in enhancing treatment precision and effectiveness.

Free-Standing Hierarchically Porous Silica Nanoparticle Superstructures: Bridging the Nano- to Microscale for Tailorable Delivery of Small and Large Therapeutics

Nanoscale colloidal self-assembly is an exciting approach to yield superstructures with properties distinct from those of individual nanoparticles. However, the bottom-up self-assembly of 3D nanoparticle superstructures typically requires extensive chemical functionalization, harsh conditions, and a long preparation time, which are undesirable for biomedical applications. Here, we report the directional freezing of porous silica nanoparticles (PSiNPs) as a simple and versatile technique to create anisotropic 3D superstructures with hierarchical porosity afforded by microporous PSiNPs and newly generated meso- and macropores between the PSiNPs. By varying the PSiNP building block size, the interparticle pore sizes can be readily tuned. The newly created hierarchical pores greatly augment the loading of a small molecule-anticancer drug, doxorubicin (Dox), and a large macromolecule, lysozyme (Lyz). Importantly, Dox loading into both the micro- and meso/macropores of the nanoparticle assemblies not only gave a pore size-dependent drug release but also significantly extended the drug release to 25 days compared to a much shorter 7 or 11 day drug release from Dox loaded into either the micro- or meso/macropores only. Moreover, a unique temporal drug release profile, with a higher and faster release of Lyz from the larger interparticle macropores than Dox from the smaller PSiNP micropores, was observed. Finally, the formulation of the Dox-loaded superstructures within a composite hydrogel induces prolonged growth inhibition in a 3D spheroid model of pancreatic ductal adenocarcinoma. This study presents a facile modular approach for the rapid assembly of drug-loaded superstructures in fully aqueous environments and demonstrates their potential as highly tailorable and sustained delivery systems for diverse therapeutics.

Multifunctional mesoporous silica nanoparticles for biomedical applications

Mesoporous silica nanoparticles (MSNs) are recognized as a prime example of nanotechnology applied in the biomedical field, due to their easily tunable structure and composition, diverse surface functionalization properties, and excellent biocompatibility. Over the past two decades, researchers have developed a wide variety of MSNs-based nanoplatforms through careful design and controlled preparation techniques, demonstrating their adaptability to various biomedical application scenarios. With the continuous breakthroughs of MSNs in the fields of biosensing, disease diagnosis and treatment, tissue engineering, etc., MSNs are gradually moving from basic research to clinical trials. In this review, we provide a detailed summary of MSNs in the biomedical field, beginning with a comprehensive overview of their development history. We then discuss the types of MSNs-based nanostructured architectures, as well as the classification of MSNs-based nanocomposites according to the elements existed in various inorganic functional components. Subsequently, we summarize the primary purposes of surface-functionalized modifications of MSNs. In the following, we discuss the biomedical applications of MSNs, and highlight the MSNs-based targeted therapeutic modalities currently developed. Given the importance of clinical translation, we also summarize the progress of MSNs in clinical trials. Finally, we take a perspective on the future direction and remaining challenges of MSNs in the biomedical field.

A di-electrophoretic simulation procedure of iron-oxide micro-particle drug attachment system for leukemia treatment using COMSOL software: a potential treatment reference for LMICs

Background

Leukemia encompasses various subtypes, each with unique characteristics and treatment approaches. The challenge lies in developing targeted therapies that can effectively address the specific genetic mutations or abnormalities associated with each subtype. Some leukemia cases may become resistant to existing treatments over time making them less susceptible to chemotherapy or other standard therapies.

Objective

Developing new treatment strategies to overcome resistance is an ongoing challenge particularly in Low and Middle Income Countries (LMICs). Computational studies using COMSOL software could provide an economical, fast and resourceful approach to the treatment of complicated cancers like leukemia.

Methods

Using COMSOL Multiphysics software, a continuous flow microfluidic device capable of delivering anti-leukemia drugs to early-stage leukemia cells has been computationally modeled using dielectrophoresis (DEP).

Results

The cell size difference enabled the micro-particle drug attachment to the leukemia cells using hydrodynamic focusing from the dielectrophoretic force. This point of care application produced a low voltage from numerically calculated electrical field and flow speed simulations.

Conclusion

Therefore, such a dielectrophoretic low voltage application model can be used as a computational treatment reference for early-stage leukemia cells with an approximate size of 5 μm.

Hesperidin Induced HePG-2 Cell Apoptosis through ROS-Mediated p53/Bcl-2/Bax and p-mTOR Signaling Pathways

Recently, research showed that one of the most common kinds of liver cancer is hepatocellular carcinoma (HCC), which is also the fourth main cause of cancer deaths. In studies regarding chemicals to better treat the disease, hesperidin shows a novel potential in performing anticancer activities, particularly in liver cancer. However, the specific mechanism of hesperidin that causes such activities remains a mystery. Thus, the purpose of this study is to investigate hesperidin’s effect on cell proliferation and activation of ROS-mediated signaling pathways in HePG-2 cells. Hesperidin shows a significant impact on inhibiting HePG-2 cells’ proliferation through induction of cell apoptosis by Bcl-2, Bax, and p53 pathways. Treating cells with hesperidin in a dose-dependent manner shows a significant increase in the apoptotic cell population (sub-G1). Moreover, Hesperidin’s induction of apoptotic activities shows dependence on ROS (reactive oxygen species) overproduction, further affecting the p-mTOR pathways and leading to DNA damage. Hence, the overall data demonstrate that ROS-mediated signaling pathways exhibit mechanisms that may lead to useful information for interpreting hesperidin-induced hepatocarcinoma cell apoptosis.

A review on plant polysaccharide based on drug delivery system for construction and application, with emphasis on traditional Chinese medicine polysaccharide

Carbohydrate polymers with unique chemical composition, molecular weight and functional chemical groups show multiple potentials in drug delivery. Most carbohydrate polymers such as plant polysaccharides exhibit advantages of biodegradability, ease of modification, low immunogenicity and low toxicity. They can be conjugated, cross-linked or functionally modified, and then used as nanocarrier materials. Polysaccharide drug delivery system can avoid the phagocytosis of the reticuloendothelial system, prevent the degradation of biomolecules, and increase the bioavailability of small molecules, thus exerting effective therapeutic effects. Therefore, they have been fully explored. In this paper, we reviewed the construction methods of drug delivery systems based on carbohydrate polymers (astragalus polysaccharide, angelica polysaccharide, lycium barbarum polysaccharide, ganoderma lucidum polysaccharide, bletilla polysaccharide, glycyrrhiza polysaccharide, and epimedium polysaccharides, etc). The application of polysaccharide drug delivery systems to deliver small molecule chemotherapeutic drugs, gene drugs, and metal ion drugs was also briefly introduced. At the same time, the role of the polysaccharide drug delivery system in tumor treatment, targeted therapy, and wound healing was discussed. In addition, the research of polysaccharide delivery systems based on the therapeutic efficacy of traditional Chinese medicine was also summarized and prospected.

Mechanically tuneable physical nanocomposite hydrogels from polyelectrolyte complex templated silica nanoparticles for anionic therapeutic delivery

Hydrogels have shown great promise for drug delivery and tissue engineering but can be limited in practical applications by poor mechanical performance. The incorporation of polymer grafted silica nanoparticles as chemical or physical crosslinkers in in situ polymerised nanocomposite hydrogels has been widely researched to enhance their mechanical properties. Despite the enhanced mechanical stiffness, tensile strength, and self-healing properties, there remains a need for the development of simpler and modular approaches to obtain nanocomposite hydrogels. Herein, we report a facile protocol for the polyelectrolyte complex (PEC) templated synthesis of organic-inorganic hybrid poly(ethylenimine) functionalised silica nanoparticles (PEI-SiNPs) and their use as multifunctional electrostatic crosslinkers with hyaluronic acid (HA) to form nanocomposite hydrogels. Upon mixing, electrostatic interactions between cationic PEI-SiNPs and anionic HA resulted in the formation of a coacervate nanocomposite hydrogel with enhanced mechanical stiffness that can be tuned by varying the ratios of PEI-SiNPs and HA present. The reversible electrostatic interactions within the hydrogel networks also enabled self-healing and thixotropic properties. The excess positive charge present within the PEI-SiNPs facilitated high loading and retarded the release of the anionic anti-cancer drug methotrexate from the nanocomposite hydrogel. Furthermore, the electrostatic complexation of PEI-SiNP and HA was found to mitigate haemotoxicity concerns associated with the use of high molecular weight PEI. The method presented herein offers a simpler and more versatile strategy for the fabrication of coacervate nanocomposite hydrogels with tuneable mechanical stiffness and self-healing properties for drug delivery applications.

A Review of Lignocellulosic-Derived Nanoparticles for Drug Delivery Applications: Lignin Nanoparticles, Xylan Nanoparticles, and Cellulose Nanocrystals

Due to their biocompatibility, biodegradability, and non-toxicity, lignocellulosic-derived nanoparticles are very potential materials for drug carriers in drug delivery applications. There are three main lignocellulosic-derived nanoparticles discussed in this review. First, lignin nanoparticles (LNPs) are an amphiphilic nanoparticle which has versatile interactions toward hydrophilic or hydrophobic drugs. The synthesis methods of LNPs play an important role in this amphiphilic characteristic. Second, xylan nanoparticles (XNPs) are a hemicellulose-derived nanoparticle, where additional pretreatment is needed to obtain a high purity xylan before the synthesis of XNPs. This process is quite long and challenging, but XNPs have a lot of potential as a drug carrier due to their stronger interactions with various drugs. Third, cellulose nanocrystals (CNCs) are a widely exploited nanoparticle, especially in drug delivery applications. CNCs have low cytotoxicity, therefore they are suitable for use as a drug carrier. The research possibilities for these three nanoparticles are still wide and there is potential in drug delivery applications, especially for enhancing their characteristics with further surface modifications adjusted to the drugs.