Development, characterization and in vitro bile salts binding capacity of selenium nanoparticles stabilized by soybean polypeptides.

The paper presents the positive effect of soybean polypeptides (SP) on the stability and the potential hypolipidemic effect of selenium nanoparticles (SeNPs). After preparing SeNPs, SP with different molecular weight were introduced to stabilize SeNPs. We found that the SP with molecular weight >10 kDa (SP5) had the best stabilizing effect on SeNPs. We inferred that the steric resistance resulting from the long chains of SP5 protected SeNPs from collision-mediated aggregation, and the electrostatic repulsions between SP5 and SeNPs also played a positive role in stabilizing SeNPs. The as-prepared SP5-SeNPs were spherical, amorphous and zero valent. It was proved that SeNPs were bound with SP5 through O- and N- groups in SP5, and the main forces were hydrogen bonds and van der Waals forces. The bile salts binding assay showed that the SP5-SeNPs exhibited a high binding capacity to bile salts, which indicated their potential in hypolipidemic application.

The self-assembled zein hydrolysate-curcumin nanocomplex: improvement on the stability and sustainable release of curcumin.

BACKGROUND: The bioavailability of curcumin (Cur) is generally limited by its poor stability. However, it is beneficial to improve the stability of Cur by using self-assembled zein hydrolysate (ZH) as delivery carrier. This paper aimed to explore the formation mechanism of zein hydrolysate-curcumin nanocomplexes as a function of critical micelle concentration (CMC). RESULTS: In this work, The CMC of ZH (0.535 mg mL-1 ) was obtained by the pyrene fluorescent probe method. ZH-Cur nanocomplexes undergo hydrogen bonding and hydrophobic interactions, and the fluorescence quenching effect was concentration dependent with the process of static quenching. Moreover, the differences of colloidal properties on ZH and ZH-Cur nanocomplexes were systematically compared by dynamic light scattering and scanning electron microscopy near CMC. ZH presented irregular spherical shapes and would aggregate to form micelles at the CMC and above. The tight micellar structure promoted more uniform size distribution (double peaks reduced) and higher potentials (over -30 mV) within 10 days. In addition, the nanocomplexes demonstrated an obvious core-shell structure. Within 10 days of storage, the particle size distributions were uniform and the potentials increased significantly, indicating that the micellar nanostructure made the Cur stably embedded in the hydrophobic core of ZH. Finally, ZH-Cur nanocomplexes effectively improved the water solubility and encapsulation rate (over 70%) of Cur. Moreover, over 90% of Cur was released steadily within 91 h. CONCLUSION: This work provided a theoretical basis for the application of amphiphilic peptide micellar nanostructure as novel food-grade nanocarriers to transport hydrophobic bioactive substances. © 2022 Society of Chemical Industry.

A Review of the Use of Carbon Nanotubes and Graphene-Based Sensors for the Detection of Aflatoxin M1 Compounds in Milk.

This paper presents a comprehensive review of the detection of aflatoxin compounds using carbon allotrope-based sensors. Although aflatoxin M1 and its derivative aflatoxin B1 compounds have been primarily found in milk and other food products, their presence above a threshold concentration causes disastrous health-related anomalies in human beings, such as growth impairment, underweight and even carcinogenic and immunosuppressive effects. Among the many sensors developed to detect the presence of these compounds, the employment of certain carbon allotropes, such as carbon nanotubes (CNTs) and graphene, has been highly preferred due to their enhanced electromechanical properties. These conductive nanomaterials have shown excellent quantitative performance in terms of sensitivity and selectivity for the chosen aflatoxin compounds. This paper elucidates some of the significant examples of the CNTs and graphene-based sensors measuring Aflatoxin M1 (ATM1) and Aflatoxin B1 (AFB1) compounds at low concentrations. The fabrication technique and performance of each of the sensors are shown here, as well as some of the challenges existing with the current sensors.

Gas sensing materials roadmap.

Gas sensor technology is widely utilized in various areas ranging from home security, environment and air pollution, to industrial production. It also hold great promise in non-invasive exhaled breath detection and an essential device in future internet of things. The past decade has witnessed giant advance in both fundamental research and industrial development of gas sensors, yet current efforts are being explored to achieve better selectivity, higher sensitivity and lower power consumption. The sensing layer in gas sensors have attracted dominant attention in the past research. In addition to the conventional metal oxide semiconductors, emerging nanocomposites and graphene-like two-dimensional materials also have drawn considerable research interest. This inspires us to organize this comprehensive 2020 gas sensing materials roadmap to discuss the current status, state-of-the-art progress, and present and future challenges in various materials that is potentially useful for gas sensors.

Novel Zn-Binding Peptide Isolated from Soy Protein Hydrolysates: Purification, Structure, and Digestion.

In this study, a novel Zn-binding peptide, Lys-Tyr-Lys-Arg-Gln-Arg-Trp (KYKRQRW), was purified and identified from soy protein isolate hydrolysates (SPIHs). The Zn-binding peptide exhibited improved Zn-binding capacity (83.21 ± 2.65%) than SPIH solutions. CD, NMR, and Fourier transform infrared spectroscopy were used to confirm the complexation between Zn and the peptide. The results showed that the Zn-binding peptide formed a folding structure with part of the ß-sheet (29.3-13.4%) turning into random coils (41.7-57.6%) during complexation. It was further proved that the binding sites were located at the oxygen atoms on the carboxyl group of the Trp side chain and nitrogen atoms on the amino group of the Lys side chain. Moreover, the Zn-peptide complex exhibited increased solubility than ZnSO4 during simulated gastrointestinal digestion. This study highlighted that the novel soy peptide possessed a strong zinc chelate rate and had a positive effect on the gastrointestinal stability of Zn which could be utilized as a functional ingredient in future.