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Gold nanoparticles have found their application as optical probes, antibacterial agents, catalyst and sensors. Here, we report the synthesis of gold nanoparticles (GNPs) using leaf extract (LE) of three different plants viz., Populus alba (PA), Lantana camara (LC) and Hibiscus arboreus (HA). The effect of reaction temperature and concentration of leaf extracts (LEs) were studied in detail on the synthesis and size of GNPs. The prepared GNPs were chemically characterized by UV–Vis and FTIR whereas the morphological analysis was done using DLS, TEM and SEM. When 5% PA LE was used at 65 °C, almost uniform shaped GNPs were obtained of size ~ 16.3 ± 0.7 nm. The as prepared GNPs showed antibacterial activity against both Staphylococcus aureus and Escherichia coli with MIC value of ~ 100 µg/ml. Further, these GNPs were also used for the degradation of toxic dyes viz., methylene blue (MB) and congo red (CR). Overall, present studies suggested the use of green synthesized GNPs in both biomedical and analytical field.

Fluorescent silicon NPs (Si-NPs) and 3-mercaptopropionic acid-coated CdS NPs (MPA-NPs) were prepared and conjugated with two different albumin proteins, viz., BSA (B) and HSA (H). The absorption, fluorescence, FTIR, circular dichroism, and gel electrophoresis studies confirmed the conjugation of proteins to NPs. DPPH assay confirmed that the conjugated proteins retained their functional activity even after chemical modifications. The sizes of Si-NPs by TEM were found to be ∼8.7 ± 2 nm, whereas MPA-NPs showed individual particle sizes of ∼4.6 ± 1 nm. The in vitro studies suggested that these NPs were highly biocompatible. The potential of these protein-conjugated NPs in cholesterol effluxing and fluorescence imaging was studied using two different macrophage cell lines, viz., human coronary artery endothelial cells (HCAEC) and human umbilical vein endothelial cells (HUVEC). Results suggested that HSA-conjugated NPs showed better cholesterol effluxing ability and superior penetration toward these treated ce...

Essential oils (EO), which can be extracted from different edible, therapeutic and herbal plants, have been well known as natural antimicrobial additives. However, it is usually hard to attain high antimicrobial efficacy of these EOs, when these are used in different combinations for the control of foodborne microbes, because of their low solubility in water and interactive binding. Here, we report an optimized oil-in-water (o/w) nanoemulsification process for citral and carvone which generated mean droplet size of 11–19 nm. It was found that nature of surfactant viz., Brij-58 vs leaf extract of Lantana camara (LC) plays crucial role in determining the overall stability and size of the droplets. The screened nanoemulsions (NEs), when stored for long duration, showed minimal decrease in oil content with retention of antioxidant activity. The prepared NEs documented enhanced antibacterial activity compared to pure oils whereas higher degree of killing was observed towards Pseudomonas aeruginosa. The NEs also showed killing of both the bacteria on wound dressing cotton gauze bandages (GB). The outcome of the present study may be used for the development of safe and biocompatible antibacterial agents.

Picroliv, a mixture of picroside I and kutkoside isolated from rhizome of Picrorrhiza kurroa has been reported for many pharmaceutical properties such as hepatoprotective, anticholestatic, antioxidant and immune‐modulating activity. However, picroliv possessed lesser efficacy due to its poor aqueous solubility and lesser bioavailability. To find solution, picroliv was loaded into biodegradable poly lactic acid nanoparticles (PLA NPs) using solvent evaporation method. The picroliv‐loaded PLA NPs were characterised by UV–vis spectroscopy, atomic force microscopy, transmission electron microscopy, Fourier transform infrared and Zeta sizer. The size of picroliv‐loaded PLA NPs was 182 ± 20 nm. Zeta potential of picroliv‐loaded PLA NPs was −23.5 mV, indicated their good stability. In vitro picroliv release from picroliv‐loaded PLA NPs showed an initial burst release followed by slow and sustained release. The efficacy of picroliv‐loaded PLA NPs was assessed against KB cell lines. Blank PLA NPs showed no cytotoxicity on KB cells. The picroliv‐loaded PLA NPs showed more cytotoxic activity on KB cells as compared to the pure drug. Hence, the developed picroliv nanoformulation would find potential application in pharma‐sector.

Background:Nanomaterials offer significant advantages in delivery of different biomolecules which suffer from drawbacks like poor bioavailability, low stability and retention time, degradation in biological systemsetc. Nanotechnological approach has shown promising results for the sustained release of these biomolecules with minimal toxicity concerns. The present review describes a comprehensive outlook of the different nanomaterials used for the delivery of these biomolecules.Methods:Current literature reports related to protein, peptide and gene delivery agents have been reviewed and classified according to their applications.Results:Studies suggested that the nanomaterial based delivery agents can be broadly classified in to five categories which include metallic NPs, polymeric NPs, magnetic NPs, liposomes and micelles. All these materials provided significant improvement in the targeted delivery of biomolecules.Conclusion:Concerns regarding the bioavailability, stability and delivery of proteins, peptides, genes need to be investigated to improve their therapeutic potential in the biological milieu. The use of nanoparticles as drug delivery vehicles may avoid undesirable hazards and may increase their pharmaceutical efficacy.

In this study, three plants Populus alba, Hibiscus arboreus and Lantana camara were explored for the synthesis of silver nanoparticles (SNPs). The effect of reaction temperature and leaf extract (LE) concentration of P. alba, H. arboreus and L. camara was evaluated on the synthesis and size of SNPs. The SNPs were characterised by ultra-violet-visible spectroscopy, scanning electron microscopy and atomic force microscopy. The synthesis rate of SNPs was highest with LE of L. camara followed by H. arboreus and P. alba under similar conditions. L. camara LE showed maximum potential of smaller size SNPs synthesis, whereas bigger particles were formed by H. arboreous LE. The size and shape of L. camara LE synthesised SNPs were analysed by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). TEM analysis revealed the formation of SNPs of average size 17 ± 9.5 nm with 5% LE of L. camara. The SNPs synthesised by LE of L. camara showed strong antibacterial activity against Escherichia coli. The results document that desired size SNPs can be synthesised using these plant LEs at a particular temperature for applications in the biomedical field.

Nanotechnology has now reached to a stage where the nanoparticles (NPs) have been in applicability in wide-ranging realms of science and technology. NPs are the materials with at least one dimension in the order of 100 nm or less. NPs display astonishing properties of high surface/volume ratio and enhanced physical, chemical, optical, and thermal properties which are extremely different than their bulk materials. The conventional methods of synthesis of nanocompounds involve the employment of physical and chemical methods, which have few drawbacks such as the requirement of toxic hazardous chemicals, energy intensive, and costly processes make it difficult to be widely implemented. To overcome these limitations, the researchers have looked forward for an easy and feasible alternative approach for the synthesis of nanocompounds. The employment of alternative biogenic route for the NP synthesis by using biological entities of unicellular living organisms such as bacteria, fungi, and actinomycetes has sought apparent attention of the scientists throughout the global earth. A greener approach interconnecting nanobiology with microbial biotechnology is responsible for the formation of NPs mediated by microbes that allow synthesis in aqueous environment, with low energy consumption and at low costs. Biosynthesis of gold, silver, copper, quantum dots, and magnetite NPs by bacteria, fungi, actinomycetes, and yeasts has been reported. In a view to form noble metal NPs of uniform shape and size, biological routes using microbial cultures at optimal temperature, pressure, and pH have been formulated. In this chapter, the main focus is given on the intracellular and extracellular approaches used for synthesis of metallic NPs by various microbial species. A detailed discussion is provided to explain the various factors which affect the synthesis of nanocompounds to further augment the growth rate of NPs as well as the mechanism of action at the cellular, biochemical, and molecular level. A great stress is given on the role of these nanocompounds in the medical field for the diagnostic and disease treatment. The potential of great biodiversity of microbial cultures as biological candidates leading to the manufacturing of NPs is needed to be fully investigated.

Liposomes and phytosomes are kind of nanoparticles (NPs) which serve as an imperative tool for the delivery of various bioactive molecules. The molecules possessing lesser water solubility, bioavailability and retention time are encapsulated into both of these formulations. More specifically, liposomes can encapsulate both hydrophobic as well as hydrophilic molecules. While phytosomes contain only plant-based molecules having poor solubility in biological media like flavanones and terpenes. The various advantages of liposomes and phytosomes like biocompatibility, nontoxicity, ease to administer, decrease in dosage and increase in retention time make them potent vehicles for the drug delivery of various molecules. These nanoformulations find potential applications for delivery of various bioactive molecules, in tissue regeneration and as antimicrobials. This chapter highlights the importance of liposomes and phytosomes, methods of their preparation, mechanism of their action and applications.

The metallic nanoparticles (NPs) and their synthetic biology are an active area fascinating both the academics as well as scientific research applications in the field of nanotechnology. These nanostructures are a versatile class of materials such as metal NPs, metal oxide NPs, magnetic NPs and quantum dots for biomedical sciences and engineering due to their huge potential. A handful number of methods are adopted for the synthesis of one or the other kind of metal NPs which includes physical and chemical approaches. Each of the chemical and physical synthesis procedures deals with some limitations such as cost ineffectiveness, use of hazardous chemicals, formation of toxic end products and involvement of high-energy processes. To overcome these drawbacks, an alternative approach of environmentally benign and inexpensive biological synthesis mediated by plants or microbes has been essentially adopted. The variations in size, shape and surface chemistry of NPs affect the properties of metal NPs to a greater extent which in turn have an influence on their biological behaviour. Few metal NPs offer unique optical properties while others possess paramagnetic behaviour and quantum size effect which make them suitable in bio-imaging diagnostic techniques. Some metallic NPs play a role in tissue engineering and other therapeutic applications due to their ease of surface modifications, large surface area to volume ratio, unique electrical and anti-microbial activities. Instead of multi-disciplinary applications of metallic NPs, there is a great concern regarding the toxicity issues associated with the use of these NPs which need to be sorted out by looking out certain ways for favourable architecture involving the synthesis methods and parameters for designing the non-toxic NPs for improving the quality of life.

Nanoparticles (NPs) are being extensively used in the field of nanomedicines. Different types of NPs are administered into the body by various routes. NPs come in contact with cells inside the body. Cellular response of NPs is affected by size, shape, surface chemistry, and cellular uptake pathways of NPs. In addition to this, type of cells, various cell lines, and growth media are also found to affect the cellular response of NPs. NPs induce diverse cellular responses like apoptosis, necrosis, and reactive oxygen species (ROS) production. NPs also form a protein corona inside the biological media which may alter their identity and behaviour as compared to bare NPs. In this chapter, we have made an attempt to throw light on cellular uptake pathways of NPs, monitoring of endocytic pathways followed by NPs, factors affecting cellular responses of therapeutic NPs, and protein corona formation, characterisation and its implications on fate of NPs.

Nanoscale materials (NSMs) are gaining attention due to their small size and unique physiochemical properties. Different approaches are used for the synthesis of NSMs. NSMs cannot be visualized by ordinary instruments. Instruments with high resolution are required for their characterisation. NSMs offer enhanced activity and specificity to encapsulate drugs. NSM are used as vehicles for site specific delivery of drugs inside the body. In this chapter, approaches for the synthesis of NSMs, and characterisation techniques for NSMs like SEM, TEM, AFM, DLS, XRD, and FTIR have been explained briefly. In addition, this chapter also covers zero dimensional one dimensional, two dimensional and three dimensional NSMs briefly. Detailed information about approaches of targeted delivery like passive and active have been covered in this chapter. NSMs like polymeric nanoparticles, metallic nanoparticles, liposomes, quantum dots, polymeric micelles, carbon nanotubes, dendrimers, and magnetic nanoparticles used in targeted drug delivery have also been explained in this chapter.

Biodegradable nanoparticles (BNPs) are seeking augmented attention for their ability to serve as a carrier for site-specific delivery of drugs, biomolecules, proteins and peptides in the body. They offer enhanced biocompatibility, better drug encapsulation and sustained release profile of a great number of drugs and biomolecules to be used in a variety of applications in nanomedicine. The use of BNPs for controlled drug delivery has shown significant therapeutic potential. Concurrently, targeted delivery technologies are becoming an increasingly important area of scientific investigation. The fate of BNPs is decided by virtue of their physiochemical properties in biological medium. Another important area which is gaining attention of researchers is the behaviour of BNPs in biological milieu. In the present chapter, efforts are made to give the readers a comprehensive outlook of the topic covering the following major points: (1) brief introduction to BNPs; (2) synthesis methodologies of BNPs; (3) characterisation of BNPs; (4) BNPs for drug delivery; (5) drug release mechanisms from BNPs; (6) targeted drug delivery using BNPs; (7) biological barriers encountered by BNPs; and (8) in vivo fate of BNPs.