No abstract

No abstract

No abstract

The clinical need for photodynamic therapy (PDT) has been growing for several decades. Notably, PDT is often used in oncology to treat a variety of tumors since it is a low-risk therapy with excellent selectivity, does not conflict with other therapies, and may be repeated as necessary. The mechanism of action of PDT is the photoactivation of a particular photosensitizer (PS) in a tumor microenvironment in the presence of oxygen. During PDT, cancer cells produce singlet oxygen (1O2) and reactive oxygen species (ROS) upon activation of PSs by irradiation, which efficiently kills the tumor. However, PDT’s effectiveness in curing a deep-seated malignancy is constrained by three key reasons: a tumor’s inadequate PS accumulation in tumor tissues, a hypoxic core with low oxygen content in solid tumors, and limited depth of light penetration. PDTs are therefore restricted to the management of thin and superficial cancers. With the development of nanotechnology, PDT’s ability to penetrate deep tumor tissues and exert desired therapeutic effects has become a reality. However, further advancement in this field of research is necessary to address the challenges with PDT and ameliorate the therapeutic outcome. This review presents an overview of PSs, the mechanism of loading of PSs, nanomedicine-based solutions for enhancing PDT, and their biological applications including chemodynamic therapy, chemo-photodynamic therapy, PDT–electroporation, photodynamic–photothermal (PDT–PTT) therapy, and PDT–immunotherapy. Furthermore, the review discusses the mechanism of ROS generation in PDT advantages and challenges of PSs in PDT.

No abstract

: Exosomes are nano structured (50-90 nm) vesicles that originate from endosomal compartment of eukaryotic cells and are secreted into extracellular matrix. In recent years there has been increased interest in exploring exosomes for diagnostic and therapeutic applications. Like many other diseases e.g. neurodegenerative disorders, autoimmune diseases exosomes have large significance in cancer too. Exosomes are known to prevail in large numbers and carry unique cargos in different types of cancers and thus are proving as versatile entities in understanding their biology of cancers and utilized as efficient diagnostic biomarkers in identification of cancer type. In addition to diagnostic applications there has been an increased interest in recent years to exploit exosomes as carriers for delivery of therapeutic agents to target sites as well. This is indebted to their exceptional non-immunogenic and biomimetic properties that prompted researchers to use exosomes as carriers for delivery of therapeutic agents e.g. drugs, genes and peptides. Exosomes also circumvent many drawbacks associated with other lipid or polymeric nanocarriers e.g. low circulation time, lipid toxicities, long term stability etc. However, in spite of many favorable aspects for exosome based therapy there have been a number of challenges too. This review will focus on the current status of the exosome based drug therapy for cancer, the challenges faced and its potential for future clinical use.

No abstract

Abstract:: Carbon nanotubes are nano sized cylindrical chicken wire like structures made of carbon atoms. Carbon nanotubes have applications in electronics, energy storage, electromagnetic devices, environmental remediation and in medicine as well. The biomedical applications of carbon nanotubes can be owed to features like low toxicity, non-immunogenicity, high in vivo stability and rapid cell entry etc. Carbon nanotubes have great prospect in the treatment of diseases through diagnostic as well as therapeutic approaches. These nanostructures are interesting carriers for delivery and translocation of therapeutic molecules e.g. proteins, peptides, nucleic acids, drugs etc. to various organs like brain, lungs, liver, pancreas etc. Commonly used methods to synthesize carbon nanotubes are arc discharge, chemical vapor deposition, pyrolysis, laser ablation etc. These methods have many disadvantages such as operation at high temperature, use of chemical catalysts, prolonged synthesis time and inclusion of toxic metallic particles in the final product requiring additional purification processes. In order to avoid these setbacks various green chemistry based synthetic methods have been devised e.g. those involving interfacial polymerization, supercritical carbon dioxide drying, plant extract assisted synthesis, water assisted synthesis etc. This review will provide a thorough outlook of the eco-friendly synthesis of carbon nanotubes reported in literature and their biomedical applications. Besides, the most commonly used spectroscopic techniques used for the characterization of carbon nanotubes are also discussed.