A Survey on Analytical Methods for the Characterization of Green Synthesized Nanomaterials

Classification and design strategies of polysaccharide-based nano-nutrient delivery systems for enhanced bioactivity and targeted delivery: A review

Since many nutrients are highly sensitive, they cannot be absorbed and utilized efficiently by the body. Using nano-delivery systems to encapsulate nutrients is an effective method of solving the problems associated with the application of nutrients at this stage. Polysaccharides, as natural biomaterials, have a unique chemical structure, ideal biocompatibility, biodegradability and low immunogenicity. This makes polysaccharides powerful carriers that can enhance the biological activity of nutrients. However, the true role of polysaccharide-based delivery systems requires an in-depth understanding of the structural and physicochemical characteristics of polysaccharide-based nanodelivery systems, as well as effective modulation of the intestinal delivery mechanism and the latest advances in nano-encapsulation. This review provides an overview of polysaccharide-based nano-delivery systems dependent on different carrier types, emphasizing recent advances in the application of polysaccharides, a biocomposite material designed for nutrient delivery systems. Strategies for polysaccharide-based nano-delivery systems to enhance the bioavailability of orally administered nutrients from the perspective of the intestinal absorption barrier are presented. Characterization methods for polysaccharide-based nano-delivery systems are presented as well as an explanation of the formation mechanisms behind nano-delivery systems from the perspective of molecular forces. Finally, we discussed the challenges currently facing polysaccharide-based nano-delivery systems as well as possible future directions for the future.

Revisiting the Green Synthesis of Nanoparticles: Uncovering Influences of Plant Extracts as Reducing Agents for Enhanced Synthesis Efficiency and Its Biomedical Applications

Background

Conventional nanoparticle synthesis methods involve harsh conditions, high costs, and environmental pollution. In this context, researchers are actively searching for sustainable, eco-friendly alternatives to conventional chemical synthesis methods. This has led to the development of green synthesis procedures among which the exploration of the plant-mediated synthesis of nanoparticles experienced a great development. Especially, because plant extracts can work as reducing and stabilizing agents. This opens up new possibilities for cost-effective, environmentally-friendly nanoparticle synthesis with enhanced size uniformity and stability. Moreover, bio-inspired nanoparticles derived from plants exhibit intriguing pharmacological properties, making them highly promising for use in medical applications due to their biocompatibility and nano-dimension.

Objective

This study investigates the role of specific phytochemicals, such as phenolic compounds, terpenoids, and proteins, in plant-mediated nanoparticle synthesis together with their influence on particle size, stability, and properties. Additionally, we highlight the potential applications of these bio-derived nanoparticles, particularly with regard to drug delivery, disease management, agriculture, bioremediation, and application in other industries.

Methodology

Extensive research on scientific databases identified green synthesis methods, specifically plant-mediated synthesis, with a focus on understanding the contributions of phytochemicals like phenolic compounds, terpenoids, and proteins. The database search covered the field's development over the past 15 years.

Results

Insights gained from this exploration highlight plant-mediated green synthesis for cost-effective nanoparticle production with significant pharmacological properties. Utilizing renewable biological resources and controlling nanoparticle characteristics through biomolecule interactions offer promising avenues for future research and applications.

Conclusion

This review delves into the scientific intricacies of plant-mediated synthesis of nanoparticles, highlighting the advantages of this approach over the traditional chemical synthesis methods. The study showcases the immense potential of green synthesis for medical and other applications, aiming to inspire further research in this exciting area and promote a more sustainable future.

Biosynthesized δ-Bi2O3 Nanoparticles from Crinum viviparum Flower Extract for Photocatalytic Dye Degradation and Molecular Docking

Bioinspired delta-bismuth oxide nanoparticles (δ-Bi₂O₃ NPs) have been synthesized using a greener reducing agent and surfactant via co-precipitation method. The originality of this work is the use of Crinum viviparum flower extract for the first time for the fabrication of NPs, which were further calcined at 800 °C to obtain δ-Bi₂O₃ NPs. Physicochemical studies such as FTIR spectroscopy and XPS confirmed the formation of Bi₂O₃ NPs, whereas XRD and Raman verified the formation of the cubic delta (δ) phase of Bi₂O₃ NPs. However, HRTEM revealed the spherical shape with diameter 10-20 nm, while BET studies expose mesoporous nature with a surface area of 71 m²/gm. The band gap for δ-Bi₂O₃ NPs was estimated to be 3.45 eV, which ensured δ-Bi₂O₃ to be a promising photocatalyst under visible-light irradiation. Therefore, based on the results of physicochemical studies, the bioinspired δ-Bi₂O₃ NPs were explored as active photocatalysts for the degradation of toxic dyes, viz., Thymol blue (TB) and Congo red (CR) under visible-light irradiation. The study showed 98.26% degradation of TB in 40 min and 69.67% degradation of CR in 80 min by δ-Bi₂O₃ NPs. The photogenerated holes and electrons were found responsible for this enhancement. Furthermore, molecular docking investigations were also performed for δ-Bi₂O₃ NPs to understand its biological function as New Delhi metallo-β-lactamase 1 (NDM-1) [PDB ID 5XP9] enzyme inhibitor, and studies revealed good interaction with various amino acid residues and found good hydrogen bonding with a fine pose energy of -3.851 kcal/mole.

Synthesis of silymarin-selenium nanoparticle conjugate and examination of its biological activity in vitro

Silymarin (Sil) was conjugated to selenium nanoparticles (SeNPs) to increase Sil bioavailability. The conjugates were monodisperse; the average diameter of the native SeNPs was ~ 20-50 ± 1.5 nm, whereas that of the conjugates was 30-50 ± 0.5 nm. The use of SeNPs to increase the bioavailability of Sil was examined with the MH-22a, EPNT-5, HeLa, Hep-2, and SPEV-2 cell lines. The EPNT-5 (glioblastoma) cells were the most sensitive to the conjugates compared to the conjugate-free control. The conjugates increased the activity of cellular dehydrogenases and promoted the penetration of Sil into the intracellular space. Possibly, SeNPs play the main part in Sil penetration of cells and Sil penetration is not associated with phagocytosis. Thus, SeNPs are promising for use as a Sil carrier and as protective antigens.

Building the Bridge From Aquatic Nanotoxicology to Safety by Design Silver Nanoparticles

Nanotechnologies have rapidly grown, and they are considered the new industrial revolution. However, the augmented production and wide applications of engineered nanomaterials (ENMs) and nanoparticles (NPs) inevitably lead to environmental exposure with consequences on human and environmental health. Engineered nanomaterial and nanoparticle (ENM/P) effects on humans and the environment are complex and largely depend on the interplay between their peculiar properties such as size, shape, coating, surface charge, and degree of agglomeration or aggregation and those of the receiving media/body. These rebounds on ENM/P safety and newly developed concepts such as the safety by design are gaining importance in the field of sustainable nanotechnologies. This article aims to review the critical characteristics of the ENM/Ps that need to be addressed in the safe by design process to develop ENM/Ps with the ablility to reduce/minimize any potential toxicological risks for living beings associated with their exposure. Specifically, we focused on silver nanoparticles (AgNPs) due to an increasing number of nanoproducts containing AgNPs, as well as an increasing knowledge about these nanomaterials (NMs) and their effects. We review the ecotoxicological effects documented on freshwater and marine species that demonstrate the importance of the relationship between the ENM/P design and their biological outcomes in terms of environmental safety.