Comparative study in physico-chemical properties of gelatin derivatives and their microspheres as carriers for controlled release of green tea's extract

Soy protein interactions with polyphenols: Structural and functional changes in natural and cationized forms

Herein, cationic soy protein (NSPI) was synthesized by grafting Ethylenediamine (EDA) onto soy protein isolate (SPI), and protein-gallic acid (GA) complexes were formed by mixing NSPI with GA in various ratios. We assessed the structure, particle size, thermal stability, emulsifying ability, and antioxidant capacity of NSPI and complexes. Results show that grafting with EDA introduced a positive charge to SPI and resulted in a uniform particle size, and enhanced thermal stability, emulsifying ability, and antioxidant capacity. In addition, NSPI presented more amino groups and stronger interactions with GA compared to SPI. EDA and GA synergistically increased the flexibility of SPI, reducing the α-helix content and increasing the random coil content. Moreover, the interactions between SPI, NSPI, and GA were static, and hydrophobic and electrostatic between GA and SPI and NSPI, respectively. Grafting SPI with EDA improved functionality and interactions with GA, implying that NSPI-GA complexes may function as emulsifiers and antioxidants.

Microfluidic Formulation of Curcumin-Loaded Multiresponsive Gelatin Nanoparticles for Anticancer Therapy

Current anticancer research shows that a combination of multiple treatment methods can greatly improve the killing of tumor cells. Using the latest microfluidic swirl mixer technology, combined with chemotherapy and photothermal-ablation therapy, we developed multiresponsive targeted antitumor nanoparticles (NPs) made of folate-functionalized gelatin NPs under 200 nm in size and with encapsulated CuS NPs, Fe₃O₄ NPs, and curcumin (Cur). By exploring gelatin's structure, adjusting its concentration and pH, and fine-tuning the fluid dynamics in the microfluidic device, the best preparation conditions were obtained for gelatin NPs with an average particle size of 90 ± 7 nm. The comparative targeting of the drug delivery system (DDS) was demonstrated on lung adenocarcinoma A549 cells (low level of folate receptors) and breast adenocarcinoma MCF-7 cells (high level of folate receptors). Folic acid helps achieve targeting and accurate delivery of NPs to the MCF-7 tumor cells. The synergistic photothermal ablation and curcumin's anticancer activity are achieved through infrared light irradiation (980 nm), while Fe₃O₄ is guided with an external magnetic field to target gelatin NPs and accelerate the uptake of drugs, thus efficiently killing tumor cells. The method described in this work is simple, easy to repeat, and has great potential to be scaled up for industrial production and subsequent clinical use.

Preparation and characterization of a novel controlled-release nano-delivery system loaded with pyraclostrobin via high-pressure homogenization

BACKGROUND

The development of efficient and safe green pesticides is a scientific strategy to alleviate current pesticide residues, environmental pollution, and threats to non-target organisms. Pesticide controlled-release formulations (CRFs) have attracted wide attention because they can control the rate of release of active ingredients and prolong the effective duration. In particular, nanoscale pesticide sustained-release systems have excellent biological activity and distribution performance because of their small particle size. Some technical difficulties remain in obtaining nanoscale CRFs.

RESULTS

We successfully fabricated pyraclostrobin nanosphere CRF by combining high-pressure homogenization technology and emulsion-solvent evaporation methods. The pyraclostrobin nanospheres had a uniform spherical shape with a mean particle size of 450 nm and polydispersity index of less than 0.3. The pyraclostrobin loading capacity reached 53.6%, with excellent storage stability. The contact angle of nanospheres on cucumber leaf surfaces demonstrated that it had good wettability. Compared with pyraclostrobin technical and commercial formulations, the nanosphere systems showed a significantly sustained release of pyraclostrobin for longer (up to 250 h). A preliminary bioassay against Penicillium ochrochloron showed that the bioactivity and long-term efficiency of pyraclostrobin nanospheres were superior to those of the commercial formulation.

CONCLUSION

This research introduced a simple, fast, expandable method for preparing pyraclostrobin nanospheres. The results showed that pyraclostrobin nanospheres could prolong the duration of pesticide efficacy and enhance bioactivity. Furthermore, this technology provides a platform for scale-up production of nano-scale pesticide CRFs. © 2020 Society of Chemical Industry.