A proactive model on innovative biomedical applications of gold nanoparticles

Nanocosmeceuticals: Trends and Recent Advancements in Self Care

The term cosmetics refers to any substances or products intended for external application on the skin with the aim of protection and better appearance of the skin surface. The skin delivery system promotes the controlled and targeted delivery of active ingredients. The development of this system has been driven by challenges encountered with conventional cosmeceuticals, including low skin retention of active components, limited percutaneous penetration, poor water dispersion of insoluble active ingredients, and instability of effective components. The aim is to create cosmeceuticals that can effectively overcome these issues. This review focuses on various nanocarriers used in cosmeceuticals currently and their applications in skin care, hair care, oral care, and more. The importance of nanotechnology in the sphere of research and development is growing. It provides solutions to various problems faced by conventional technologies, methods, and product formulations thus taking hold of the cosmetic industry as well. Nowadays, consumers are investing in cosmetics only for better appearance thus problems like wrinkles, ageing, hair loss, and dandruff requires to be answered proficiently. Nanocarriers not only enhance the efficacy of cosmeceutical products, providing better and longer-lasting effects, but they also contribute to the improved aesthetic appearance of the products. This dual benefit not only enhances the final quality and efficacy of the product but also increases consumer satisfaction. Additionally, nanocarriers offer protection against UV rays, further adding to the overall benefits of the cosmeceutical product. Figure 1 represents various advantages of nanocarriers used in cosmeceuticals. Nanotechnology is also gaining importance due to their high penetration of actives in the deeper layers of skin. It can be said that nanotechnology is taking over all the drawbacks of the traditional products. Thus, nanocarriers discussed in this review are used in nanotechnology to deliver the active ingredient of the cosmeceutical product to the desired site.

Effects of Different Nanoparticles on Microbes

Nanoparticles widely exist in nature and may be formed through inorganic or organic pathways, exhibiting unique physical and chemical properties different from those of bulk materials. However, little is known about the potential consequences of nanomaterials on microbes in natural environments. Herein, we investigated the interactions between microbes and nanoparticles by performing experiments on the inhibition effects of gold, ludox and laponite nanoparticles on Escherichia coli in liquid Luria–Bertani (LB) medium at different nanoparticle concentrations. These nanoparticles were shown to be effective bactericides. Scanning electron microscopy (SEM) images revealed the distinct aggregation of cells and nanoparticles. Transmission electron microscopy (TEM) images showed considerable cell membrane disruption due to nanoparticle accumulation on the cell surfaces, resulting in cell death. We hypothesized that this nanoparticle accumulation on the cell surfaces not only disrupted the cell membranes but also physically blocked the microbes from accessing nutrients. An iron-reducing bacterium, Shewanella putrefaciens, was tested for its ability to reduce the Fe (III) in solid ferrihydrite (HFO) or aqueous ferric citrate in the presence of laponite nanoparticles. It was found that the laponite nanoparticles inhibited the reduction of the Fe (III) in solid ferrihydrite. Moreover, direct contact between the cells and solid Fe (III) coated with the laponite nanoparticles was physically blocked, as confirmed by SEM images and particle size measurements. However, the laponite particles had an insignificant effect on the extent of aqueous Fe (III) bioreduction but slightly enhanced the rate of bioreduction of the Fe (III) in aqueous ferric citrate. The slightly increased rate of bioreduction by laponite nanoparticles may be due to the removal of inhibitory Fe (II) from the cell surface by its sorption onto the laponite nanoparticle surface. This result indicates that the scavenging of toxic heavy metals, such as Fe (II), by nanoparticles may be beneficial for microbes in the environment. On the other hand, microbial cells are also capable of detoxifying nanoparticles by coagulating nanoparticles with extracellular polymeric substances or by changing nanoparticle morphologies. Hence, the interactions between microbes and nanoparticles in natural environments should receive more attention.

Optical Force and Torque on a Graphene-Coated Gold Nanosphere by a Vector Bessel Beam

In the framework of the generalized Lorenz–Mie theory (GLMT), the optical force and torque on a graphene-coated gold nanosphere by a vector Bessel beam are investigated. The core of the particle is gold, whose dielectric function is given by the Drude–Sommerfeld model, and the coating is multilayer graphene with layer number N, whose dielectric function is described by the Lorentz–Drude model. The axial optical force Fz and torque Tz are numerically analyzed, and the effects of the layer number N, wavelength λ, and beam parameters (half-cone angle α0, polarization, and order l) are mainly discussed. Numerical results show that the optical force and torque peaks can be adjusted by increasing the thickness of the graphene coating, and can not be adjusted by changing α0 and l. However, α0 and l can change the magnitude of the optical force and torque. The numerical results have potential applications involving the trapped graphene-coated gold nanosphere.

Nanotechnology in Cosmetics and Cosmeceuticals—A Review of Latest Advancements

Nanotechnology has the potential to generate advancements and innovations in formulations and delivery systems. This fast-developing technology has been widely exploited for diagnostic and therapeutic purposes. Today, cosmetic formulations incorporating nanotechnology are a relatively new yet very promising and highly researched area. The application of nanotechnology in cosmetics has been shown to overcome the drawbacks associated with traditional cosmetics and also to add more useful features to a formulation. Nanocosmetics and nanocosmeceuticals have been extensively explored for skin, hair, nails, lips, and teeth, and the inclusion of nanomaterials has been found to improve product efficacy and consumer satisfaction. This is leading to the replacement of many traditional cosmeceuticals with nanocosmeceuticals. However, nanotoxicological studies on nanocosmeceuticals have raised concerns in terms of health hazards due to their potential skin penetration, resulting in toxic effects. This review summarizes various nanotechnology-based approaches being utilized in the delivery of cosmetics as well as cosmeceutical products, along with relevant patents. It outlines their benefits, as well as potential health and environmental risks. Further, it highlights the regulatory status of cosmeceuticals and analyzes the different regulatory guidelines in India, Europe, and the USA and discusses the different guidelines and recommendations issued by various regulatory authorities. Finally, this article seeks to provide an overview of nanocosmetics and nanocosmeceuticals and their applications in cosmetic industries, which may help consumers and regulators to gain awareness about the benefits as well as the toxicity related to the continuous and long-term uses of these products, thus encouraging their judicious use.

Formation of Gold Nanoparticles in Water-in-Oil Microemulsions: Experiment, Mechanism, and Simulation

Self-assembled water-in-oil (W/O) microemulsions have been reported as a suitable route for synthesis of size-controlled nanoparticles. However, the mechanism of formation of nanoparticles in microemulsions is still not completely understood. In this work, gold nanoparticles (GNPs) were synthesized via the W/O microemulsion route. As the molar ratio of water and dioctyl sodium sulphosuccinate (AOT) (R) increased from 2.5 to 5.0 to 7.5, the corresponding water drop diameter increased from 2.7 to 5.0 to 7.3 nm. In parallel, the mean hydrodynamic diameter of GNPs increased from 6.5 to 11.3 to 15.6 nm for corresponding R values of 2.5, 5.0, and 7.5. Therefore, although there is a monotonically increasing trend of the mean diameter of GNPs with the initial drop diameter, for all values of R, the mean diameter of GNPs was significantly higher than the initial drop diameter. Consequently, previously known simulation vastly underpredicts the experimental GNP diameter. However, only on redefining the particle-particle coagulation event (during coalescence of microemulsion drops containing particles) does the current kinetic Monte Carlo (kMC) simulation agree well with the experimental results. In addition, we also find that the coagulation efficiency of solid nanoparticles (β_p) increases with R, and β_p is lesser than the coalescence efficiency of liquid drops (β_d) over the range of R values concerned. Hence, a combined simulation and experimental study enumerates the dynamics of size evolution of nanoparticles and the events involved in their formation in a W/O microemulsion system.

Nanotechnology-Based Approach to Combat Pandemic COVID 19: A Review

The emergence of a novel Corona virus (COVID 19) originated on December 19 from China. The city of Wuhan, the capital city of Hubei province, China, is responsible for an outbreak of respiratory illness known as COVID 19 and it has been rapidly spread across the world claiming millions of lives. The sudden outbreak of novel Coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 or 2019-nCoV), is a big concern for their speedy mitigation using the predictable treatment and creating its approach around the world. Researchers and doctors are in search of rapid diagnosis kit, drugs, and viral-resistant personal protective equipment (PPE) to clinical diagnosis, medication, and prevent the spread of COVID 19. A rational approach with adaptability and broad viewpoint to challenge the growing pain could be overcome by the application of appropriate technology. The nanotechnology-based approach can significantly serve the purpose of the current pandemic situation of COVID 19. But same time implementation of innovative and creative nanotech approach, there is a decisive need for the full knowledge of SARS-CoV-2 pathogenesis. Moreover, to defeat COVID 19, particularly nanotech-based system with their viral inhibitory properties to increase the effective nanotech approach is essential. In this scenario, this review aims to summarize the past, present, and future of nanotech-based systems that can be used to treat COVID 19, highlighting Nano-based compounds. Lastly, the potential application of the different category of Inorganic Nanomaterials/Inorganic organic conjugate /hybrid system and their practical applicability as suitable means for inspiring against COVID 19 has also been discussed.

Biogenic synthesis of gold nanoparticles using Argemone mexicana L. and their cytotoxic and genotoxic effects on human colon cancer cell line (HCT-15)

Background

Nanomedicine has evolved as precision medicine in novel therapeutic approach of cancer management. The present study investigated the efficacy of biogenic gold nanoparticles synthesized using Argemone mexicana L. aqueous extract (AM-AuNPs) against the human colon cancer cell line, HCT-15.

Results

Biosynthesis of AM-AuNPs was determined by ultraviolet-visible spectroscopy and further characterized by transmission electron microscopy, X-ray diffraction, and Fourier transition infrared spectroscopy analysis. The cytotoxic activity of AM-AuNPs was assessed by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, whereas genotoxicity was evaluated by the DNA fragmentation assay. The expression of apoptosis regulatory genes such as p53 and caspase-3 was explored through semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and western blotting to evidence apoptotic cell death in HCT-15 cells. Biogenic AM-AuNPs inhibited cell proliferation in HCT-15 cell line with a half maximal inhibitory concentration (IC₅₀) of 20.53 μg/mL at 24 h and 12.03 μg/mL at 48 h of exposure. The altered cell morphology and increased apoptosis due to AM-AuNPs were also evidenced through nuclear DNA fragmentation and upregulated expression of p53 and caspase-3 in HCT-15 cells.

Conclusion

The AM-AuNPs may exert antiproliferative and genotoxic effects on HCT-15 cells by cell growth suppression and induction of apoptosis mediated by activation of p53 and caspase-3 genes.