Preparation and characterization of sodium alginate/phosphate-stabilized amorphous calcium carbonate nanocarriers and their application in the release of curcumin

CaCO3 nanoplatform for cancer treatment: drug delivery and combination therapy

The use of nanocarriers for drug delivery has opened up exciting new possibilities in cancer treatment. Among them, calcium carbonate (CaCO3) nanocarriers have emerged as a promising platform due to their exceptional biocompatibility, biosafety, cost-effectiveness, wide availability, and pH-responsiveness. These nanocarriers can efficiently encapsulate a variety of small-molecule drugs, proteins, and nucleic acids, as well as co-encapsulate multiple drugs, providing targeted and sustained drug release with minimal side effects. However, the effectiveness of single-drug therapy using CaCO3 nanocarriers is limited by factors such as multidrug resistance, tumor metastasis, and recurrence. Combination therapy, which integrates multiple treatment modalities, offers a promising approach for tackling these challenges by enhancing efficacy, leveraging synergistic effects, optimizing therapy utilization, tailoring treatment approaches, reducing drug resistance, and minimizing side effects. CaCO3 nanocarriers can be employed for combination therapy by integrating drug therapy with photodynamic therapy, photothermal therapy, sonodynamic therapy, immunotherapy, radiation therapy, radiofrequency ablation therapy, and imaging. This review provides an overview of recent advancements in CaCO3 nanocarriers for drug delivery and combination therapy in cancer treatment over the past five years. Furthermore, insightful perspectives on future research directions and development of CaCO3 nanoparticles as nanocarriers in cancer treatment are discussed.

Preparation of pH-sensitive chitosan-deoxycholic acid-sodium alginate nanoparticles loaded with ginsenoside Rb1 and its controlled release mechanism

Ginsenoside is a natural extract of the genus ginseng, which has tumor preventive and inhibiting effects. In this study, ginsenoside loaded nanoparticles were prepared by an ionic cross-linking method with sodium alginate to enable a sustained slow release effect of ginsenoside Rb₁ in the intestinal fluid through an intelligent response. Chitosan grafted hydrophobic group deoxycholic acid was used to synthesize CS-DA, providing loading space for hydrophobic Rb₁. Scanning electron microscopy (SEM) showed that the nanoparticles was spherical with smooth surfaces. The encapsulation rate of Rb₁ enhanced with the increase of sodium alginate concentration and could reach to 76.62 ± 1.78 % when concentration was 3.6 mg/mL. It was found that the release process of CDA-NPs was most consistent with the primary kinetic model which is a diffusion-controlled release mechanism. CDA-NPs exhibited good pH sensitivity and controlled release properties in buffer solutions of different pH's at 1.2 and 6.8. The cumulative release of Rb₁from CDA-NPs in simulated gastric fluid was <20 % within 2 h, while could release completely around 24 h in the simulated gastrointestinal fluid release system. It was demonstrated that CDA_3.6-NPs can effectively control release and intelligently deliver ginsenoside Rb₁, which is a promising alternative way for oral delivery.

Preparation and properties of environmentally benign waterborne polyurethane composites from sodium-alginate-modified nano calcium carbonate

Well-dispersed inorganic nanoparticles in organic polymers are critical in the preparation of high-performance nanocomposites. This study prepared a series of waterborne polyurethane (WPU)/calcium carbonate nanocomposites using the solution blending method. Next, FT-IR, TG-DTG and XRD tests were carried out to confirm that the biopolymer sodium alginate (SA) was successfully encapsulated on the surface of the calcium carbonate nanoparticles, and that SA achieved satisfactory surface modification of the calcium carbonate nanoparticles. The Zeta and ultraviolet (UV) absorbance test results reveal that SA-modified nano calcium carbonate (MCC) had good dispersion stability in water. The effects of the MCC dosage on the composite mechanical properties, thermal stability, and cross-sectional morphology observed by scanning electron microscopy, and the water resistance of the nanocomposite were investigated. The results reveal that the incorporation of 3wt% of MCC in WPU had stable distribution, which led to a 54% increase in the tensile strength of the nanocomposite, while maintaining excellent elongation at break (2187%) and increasing the maximum decomposition temperature to 419.6 °C. Importantly, the improved water resistance facilitates the application of this environmentally benign composite material in humid environments.

Alginate-Based Micro- and Nanosystems for Targeted Cancer Therapy

Alginates have been widely explored due to their salient advantages of hydrophilicity, biocompatibility, mucoadhesive features, bioavailability, environmentally-benign properties, and cost-effectiveness. They are applied for designing micro- and nanosystems for controlled and targeted drug delivery and cancer therapy as alginate biopolymers find usage in encapsulating anticancer drugs to improve their bioavailability, sustained release, pharmacokinetics, and bio-clearance. Notably, these nanomaterials can be applied for photothermal, photodynamic, and chemodynamic therapy of cancers/tumors. Future explorations ought to be conducted to find novel alginate-based (nano)systems for targeted cancer therapy using advanced drug delivery techniques with benefits of non-invasiveness, patient compliance, and convenience of drug administration. Thus, some critical parameters such as mucosal permeability, stability in the gastrointestinal tract environment, and drug solubility ought to be considered. In addition, the comprehensive clinical translational studies along with the optimization of synthesis techniques still need to be addressed. Herein, we present an overview of the current state of knowledge and recent developments pertaining to the applications of alginate-based micro- and nanosystems for targeted cancer therapy based on controlled drug delivery, photothermal therapy, and chemodynamic/photodynamic therapy approaches, focusing on important challenges and future directions.