pH Responsive Bioactive Lead Sulfide Nanomaterials: Protein Induced Morphology Control, Bioapplicability, and Bioextraction of Nanomaterials

Abstract

Precise morphologies of pH responsive bioactive lead sulfide nanoparticles (PbS NPs) were synthesized by using industrially and environmentally important proteins like zein and lysozyme (Lys), and a bioactive polymer diethylaminoethyl dextran chloride (DEAE). Though, proteins are not known morphology control agents, zein demonstrated a fine crystal growth control of PbS NPs better than Lys as well as DEAE, and even better than conventional surfactants known for their shape control behavior. Proteins and DEAE coated NPs thus obtained were highly pH responsive in terms of a color change from light gray (at low pH) to dark brown (at high pH). Bioapplicability of coated NPs was done by subjecting them to hemolysis. Both Lys and DEAE coated NPs did not induce any significant hemolysis and demonstrated their good compatibility and usability in systemic circulation. For their industrial scale uses, different extraction methods were proposed by using other industrially important biomolecules and ionic liquids. Alginic acid and xanthan gum were excellent complexing agents for an instant extraction of Lys and DEAE coated NPs from aqueous phase. Ionic liquid exhibited excellent extraction ability in both organic as well as aqueous phases.

Stability of astaxanthin-loaded nanostructured lipid carriers as affected by pH, ionic strength, heat treatment, simulated gastric juice and freeze–thawing

“…This result is in agreement with the observation made on the f-potential values of Ax-NLCs. Previously, similar results were also reported by Choi et al (2014), How et al (2013) and Mahal et al (2017). At high pH values the f-potential and thereby the electrostatic repulsion is still sufficiently strong to overcome attraction forces, but at low pH values it is no longer strong enough so that the attractive forces dominate, leading to nanoparticle aggregation (see Online Resource 1a).…”

“…This phenomenon can be attributed to the electrostatic screening effect, which arises from the binding tendency of Na þ to the negatively charged groups of lecithin (ÀPO 1À 4 À) and oleic acid (ÀCOO À ) on the nanoparticles surfaces, thereby reducing the net negative charge. The electrostatic screening effect (of NaCl) has also been reported in previous studies (Qian et al 2011(Qian et al , 2012Mahal et al 2017). No further changes were observed in the fpotential of Ax-NLCs samples during storage (P [ 0.05).…”

Nanotoxicity in Systemic Circulation and Wound Healing

“…However, some bioactive macromolecules like phospholipids, BSA, and zein have demonstrated their excellent potential in achieving shape controlled morphologies just like those of conventional surfactants. 203 Wherever an in situ synthesis of nanomaterials works, it produces fine coated NPs most appropriate for their applications in systemic circulation provided they induce minimum hemolysis. Otherwise, surfactant directed synthesis can be used to produce the desired morphologies of crystalline NPs that produce surfactant coated NPs 204−206 which cannot be directly used in the systemic circulation unless another coating of hemocompatible molecules is used to fully passivate the surfactant coating.…”

“…Since most of the bioactive molecules are not good shape directing agents like surfactants, it is usually difficult to achieve a desired monodisperse morphology under in situ reactions conditions. However, some bioactive macromolecules like phospholipids, BSA, and zein have demonstrated their excellent potential in achieving shape controlled morphologies just like those of conventional surfactants . Wherever an in situ synthesis of nanomaterials works, it produces fine coated NPs most appropriate for their applications in systemic circulation provided they induce minimum hemolysis.…”

Twin Function of Zein–Zinc Coordination Complex: Wheat Nutrient Enrichment and Nanoshield against Pathogenic Infection

“…Hence, a hydrophobic edible coating is a desirable solution for grains. The zein protein with a 3.8:1 ratio of hydrophobic to hydrophilic surface area that disperses well in 70–80% ethanol and is compatible to form hybrid structure could be a perfect match. − However, the challenge in zein coating has been to get continuous coating, since plasticizers were found to be essential even for a continuous coating on a planar surface. A plasticizer like oil may increase stickiness and eventually favors infection, whereas a nonsticky plasticizer like glycerol compromises the water barrier property. , Hence, hardly any study has taken forward the concept of zein coating to test food preservation.…”