Preparation and characterization of stearic acid-pullulan nanoparticles

Natural polysaccharides based self-assembled nanoparticles for biomedical applications - A review

In recent years, nanoparticles (NPs) derived from the self-assembly of natural polysaccharides have shown great potential in the biomedical field. Here, we described several self-assembly modes of natural polysaccharides in detail, summarized the natural polysaccharides mostly used for self-assembly, and provided insights into the current applications and achievements of these self-assembled NPs. As one of the most widespread substances in nature, most natural polysaccharides exhibit advantages of biodegradability, low immunogenicity, low toxicity, and degradable properties. Therefore, they have been fully explored, and the application of chitosan, hyaluronic acid, alginate, starch, and their derivatives has been extensively studied, especially in the fields of biomedical. Polysaccharides based NPs were proved to improve the solubility of insoluble drugs, enhance tissue target ability and realize the controlled and sustained release of drugs. When modified by hydrophobic groups, the amphiphilic polysaccharides can self-assemble into NPs. Other driven forces of self-assembly include electrostatic interaction and hydrogen bonds. Up to the present, polysaccharides-based nanoparticles have been widely applied for tumor treatment, antibacterial application, gene therapy, photodynamic therapy and transporting insulin.

Lysine Decorated Solid Lipid Nanoparticles of Epirubicin for Cancer Targeting and Therapy

Purpose: Cancer is an example of the most important growing diseases in human society and scientists are trying to treat it without considerable side effects on patient’s health. Solid lipids are colloidal nanoparticles that were used in drug delivery due to their several advantages.

Methods: In this work, surface modified targeted solid lipid nanoparticles (SLNs) were fabricated by nano-homogenizer using tripalmitin glyceride and stearic acid as lipid constituents. The size of nanoparticles and morphological evaluations were surveyed using particle size analyzer, scanning electron microscopy; Fourier transforms infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC).

Results: The particle size of 148.5 and appropriate polydispersity index were achieved for lipid nanoparticles with an entrapment efficiency of 86.1%. The FT-IR analysis confirmed the coupling of lysine to the free functional group of SLNs. DSC proved the conjugation of amino acid to the surface of carriers. The in vitro epirubicin (EPI) release test exhibited the further controlled release phenomenon for the lysine conjugated nanoparticles. The cytotoxicity assay showed lower IC50 of lysine conjugated SLNs of EPI on the investigated cell line.

Conclusion: These studies showed that the fabricated targeted carrier has a very remarkable anticancer effect on breast cancer cell lines in comparison with pure drug.

Synthesis and biological evaluation of biotin-conjugated Portulaca oleracea polysaccharides

Biotinylated Portulaca oleracea polysaccharide (Bio-POP) conjugates were successfully prepared by the esterification reaction. The biotinylated polysaccharide products were an off-white powder with an average degree of substitution of 42.5%. After grafting biotin onto POP, the thermal stability of Bio-POP conjugates was much higher than that of POP and the surface topography of Bio-POP was a loose and porous cross-linked structure. The cytotoxicity assay in vitro demonstrated that POP, biotin, and Bio-POP conjugates exhibited different cytotoxicity to HeLa, MCF-7, LO-2, and A549, in particular POP inhibited the growth of the A549 cell line more than other cell lines. The nuclear staining method demonstrated that Bio-POP conjugates can interfere with the apoptosis of A549 cells to some extent and the immunofluorescence staining photograph illustrated that Bio-POP conjugates induced A549 cells to exhibit immune activity. Therefore, the combination of biotin and Portulaca oleracea polysaccharides had immune synergistic therapeutic effects on A549 cells and can be applied in the field of anti-tumor conjugate drugs.

Biotin grafted onto Portulaca oleracea polysaccharides (Bio-POP) was successfully prepared by the esterification reaction. Bio-POP conjugates had an obvious effect on the proliferation of A549 cells and induced A549 cells to exhibit immune activity.

Nanoparticles Based on Hydrophobic Polysaccharide Derivatives-Formation Principles, Characterization Techniques, and Biomedical Applications

Polysaccharide (PS) nanoparticles (NP) are fascinating materials that combine huge application potential with the unique beneficial features of natural biopolymers. Different types of PS-NP can be distinguished depending on the basic preparation principles (top-down vs bottom-up vs coating of nanomaterials) and the material from which they are obtained (native PS vs chemically modified PS derivatives vs nanocomposites). This review provides a comprehensive overview of an approach towards PS-NP that has gained rapidly increasing interest within the last decade; the nanoself-assembling of hydrophobic PS derivatives. This facile process is easy to perform and offers a broad structural diversity in terms of the PS backbone and the additional functionalities that can be introduced. Fundamental principles of different NP preparation techniques along with useful characterization methods are presented in this work. A comprehensive summary of PS-NP prepared by different techniques and with various PS backbones and types/amounts of hydrophobic substituents is given. The intention is to demonstrate how different parameters determine the size, size distribution, and zeta-potential of the particles. Moreover, application trends in biomedical areas are highlighted in which tailored functional PS-NP are evaluated and constantly developed further.

Folic-acid-conjugated pullulan/poly(DL-lactide-co-glycolide) graft copolymer nanoparticles for folate-receptor-mediated drug delivery

BACKGROUND

Nanoparticles have been extensively investigated for targeted delivery of anticancer drugs. Since the folate receptor is universally over-expressed on the tumor cell membrane, folic acid is often used to modify the fate of nanoparticles in biologicals.

METHODS

To fabricate targetable nanoparticles, folic acid was conjugated to a pullulan backbone and poly(DL-lactide-co-glycolide) (PLGA) (abbreviated as FAPuLG) was conjugated. KB cells and NIH3T3-cell-bearing mice were prepared to prove folate receptor targeting of FAPuLG nanoparticles.

RESULTS AND DISCUSSION

Nanoparticles of FAPuLG copolymer that self-assembled in water were small with diameters <200 nm. Doxorubicin (DOX) as a model drug was incorporated into the FAPuLG nanoparticles that were used to treat folate receptor over-expressing KB human carcinoma cells. Fluorescence microscopy revealed that DOX-incorporated FAPuLG nanoparticles induced strong red fluorescence in the KB cells in the absence of folic acid. However, fluorescence intensity was decreased by blocking folate receptors. Antitumor activity of FAPuLG nanoparticles against KB cells in vitro was also decreased by blocking folate receptors. In animal study using near-infrared dye-conjugated FAPuLG nanoparticles, fluorescence intensity was significantly higher at KB solid tumor than that of NIH3T3.

CONCLUSIONS

The results indicate that FAPuLG nanoparticles can target the folate receptor of tumor cells. FAPuLG nanoparticles are a promising candidate for active targeting of anticancer agents.