Current Pharmaceutical Design - Volume 25, Issue 24, 2019

The conventional Drug Delivery System (DDS) has limitations such as leakage of the drug, toxicity to normal cells and loss of drug efficiency, while the stimuli-responsive DDS is non-toxic to cells, avoiding the leakage and degradation of the drug because of its targeted drug delivery to the pathological site. Thus nanomaterial chemistry enables - the development of smart stimuli-responsive DDS over the conventional DDS. Stimuliresponsive DDS ensures spatial or temporal, on-demand drug delivery to the targeted cancer cells. The DDS is engineered by using the organic (synthetic polymers, liposomes, peptides, aptamer, micelles, dendrimers) and inorganic (zinc oxide, gold, magnetic, quantum dots, metal oxides) materials. Principally, these nanocarriers release the drug at the targeted cells in response to external and internal stimuli such as temperature, light, ultrasound and magnetic field, pH value, redox potential (glutathione), and enzyme. The multi-stimuli responsive DDS is more promising than the single stimuli-responsive DDS in cancer therapy, and it extensively increases drug release and accumulation in the targeted cancer cells, resulting in better tumor cell ablation. In this regard, a handful of multi-stimuli responsive DDS is in clinical trials for further approval. A comprehensive review is crucial for addressing the existing knowledge about multi-stimuli responsive DDS, and hence, we summarized the emerging strategies in tailored ligand functionalized stimuli-responsive nanocarriers as the DDS for cancer therapies.

Nanoparticles have gained significant importance in the past two decades, due to their multifaceted applications in the field of nanomedicine. As our ecosystems and habitats are changing due to global warming, many new diseases are emerging continuously. Treating these costs a lot of money and mostly ends up in failure. In addition, frequent use of antibiotics to control the emerging diseases has led the pathogens to develop resistance to antibiotics. Hence, the nanoparticles are targeted to treat such diseases instead of the costly antibiotics. In particular, the biosynthesized nanoparticles have received considerable attention due to their simple, eco-friendly and promising activity. To highlight, microbial mediated nanoparticles have been found to possess higher activity and thus have a promising role in antimicrobial therapy to fight against the emerging drug-resistant pathogens. In this context, this review article is aimed at highlight the role of nanoparticles in the field of nanomedicine and importance of actinobacteria in the nanoparticle synthesis and their need in antimicrobial therapy. This is a comprehensive review, focusing on the potential of actinobacteria-mediated nanoparticles in the field of nanomedicine.

Background: Multimodal imaging plays an important role in the diagnosis of brain disorders. Neurological disorders need to be diagnosed at an early stage for their effective treatment as later, it is very difficult to treat them. If possible, diagnosing at an early stage can be much helpful in curing the disease with less harm to the body. There is a need for advanced and multimodal imaging techniques for the same. This paper provides an overview of conventional as well as modern imaging techniques for brain diseases, specifically for tumor imaging. In this paper, different imaging modalities are discussed for tumor detection in the brain along with their advantages and disadvantages. Conjugation of two and more than two modalities provides more accurate information rather than a single modality. They can monitor and differentiate the cellular processes of normal and diseased condition with more clarity. The advent of molecular imaging, including reporter gene imaging, has opened the door of more advanced noninvasive detection of brain tumors. Due to specific optical properties, semiconducting polymer-based nanoparticles also play a pivotal role in imaging tumors. Objective: The objective of this paper is to review nanoparticles-mediated brain imaging and disease prognosis by conventional as well as modern modal imaging techniques. Conclusion: We reviewed in detail various medical imaging techniques. This paper covers recent developments in detail and elaborates a possible research aspect for the readers in the field.

Generally, silver is considered as a noble metal used for treating burn wound infections, open wounds and cuts. However, the emerging nanotechnology has made a remarkable impact by converting metallic silver into silver nanoparticles (AgNPs) for better applications. The advancement in technology has improved the synthesis of NPs using biological method instead of physical and chemical methods. Nonetheless, synthesizing AgNPs using biological sources is ecofriendly and cost effective. Till date, AgNPs are widely used as antibacterial agents; therefore, a novel idea is needed for the successful use of AgNPs as therapeutic agents to uncertain diseases and infections. In biomedicine, AgNPs possess significant advantages due to their physical and chemical versatility. Indeed, the toxicity concerns regarding AgNPs have created the need for non-toxic and ecofriendly approaches to produce AgNPs. The applications of AgNPs in nanogels, nanosolutions, silver based dressings and coating over medical devices are under progress. Still, an improvised version of AgNPs for extended applications in an ecofriendly manner is the need of the hour. Therefore, the present review emphasizes the synthesis methods, modes of action under dissipative conditions and the various biomedical applications of AgNPs in detail.

Enzymes exhibit a great catalytic activity for several physiological processes. Utilization of immobilized enzymes has a great potential in several food industries due to their excellent functional properties, simple processing and cost effectiveness during the past decades. Though they have several applications, they still exhibit some challenges. To overcome the challenges, nanoparticles with their unique physicochemical properties act as very attractive carriers for enzyme immobilization. The enzyme immobilization method is not only widely used in the food industry but is also a component methodology in the pharmaceutical industry. Compared to the free enzymes, immobilized forms are more robust and resistant to environmental changes. In this method, the mobility of enzymes is artificially restricted to changing their structure and properties. Due to their sensitive nature, the classical immobilization methods are still limited as a result of the reduction of enzyme activity. In order to improve the enzyme activity and their properties, nanomaterials are used as a carrier for enzyme immobilization. Recently, much attention has been directed towards the research on the potentiality of the immobilized enzymes in the food industry. Hence, the present review emphasizes the different types of immobilization methods that is presently used in the food industry and other applications. Various types of nanomaterials such as nanofibers, nanoflowers and magnetic nanoparticles are significantly used as a support material in the immobilization methods. However, several numbers of immobilized enzymes are used in the food industries to improve the processing methods which not only reduce the production cost but also the effluents from the industry.

Background: Nanopharmaceuticals have rapidly emerged as a means to cure several diseases. There are numerous reports describing the development and application of nanopharmaceuticals. Here, we discussed nanoparticle synthesis and the mechanisms to scavenge free radicals. We also discuss their major properties and list several commercially available nanomedicines. Results: Reactive oxygen and hydrogen species are formed during normal metabolism, and excessive reactive species can damage proteins, lipids, and DNA and cause disease. Plant- and microbe-based nanoparticles, which can protect tissues from free radical damage, have recently gained research momentum because they are inexpensive and safe. Conclusion: Synthetic and biocompatible nanoparticles exhibit antioxidant, antidiabetic, anti-inflammatory, and anticancer properties, which can be used to treat several diseases. Further studies are needed to investigate their sizes, dose-dependent activities, and mechanisms of action.