Polyorganophosphazene stabilized gold nanoparticles for intracellular drug delivery in breast carcinoma cells

Cyclo- and Polyphosphazenes for Biomedical Applications

Cyclic and polyphosphazenes are extremely interesting and versatile substrates characterized by the presence of -P=N- repeating units. The chlorine atoms on the P atoms in the starting materials can be easily substituted with a variety of organic substituents, thus giving rise to a huge number of new materials for industrial applications. Their properties can be designed considering the number of repetitive units and the nature of the substituent groups, opening up to a number of peculiar properties, including the ability to give rise to supramolecular arrangements. We focused our attention on the extensive scientific literature concerning their biomedical applications: as antimicrobial agents in drug delivery, as immunoadjuvants in tissue engineering, in innovative anticancer therapies, and treatments for cardiovascular diseases. The promising perspectives for their biomedical use rise from the opportunity to combine the benefits of the inorganic backbone and the wide variety of organic side groups that can lead to the formation of nanoparticles, polymersomes, or scaffolds for cell proliferation. In this review, some aspects of the preparation of phosphazene-based systems and their characterization, together with some of the most relevant chemical strategies to obtain biomaterials, have been described.

Polymer-Based Hybrid Nanoarchitectures for Cancer Therapy Applications

Globally, cancer is affecting societies and is becoming an important cause of death. Chemotherapy can be highly effective, but it is associated with certain problems, such as undesired targeting and multidrug resistance. The other advanced therapies, such as gene therapy and peptide therapy, do not prove to be effective without a proper delivery medium. Polymer-based hybrid nanoarchitectures have enormous potential in drug delivery. The polymers used in these nanohybrids (NHs) provide them with their distinct properties and also enable the controlled release of the drugs. This review features the recent use of polymers in the preparation of different nanohybrids for cancer therapy published since 2015 in some reputed journals. The polymeric nanohybrids provide an advantage in drug delivery with the controlled and targeted delivery of a payload and the irradiation of cancer by chemotherapeutical and photodynamic therapy.

Engineered Hyaluronic Acid-Based Smart Nanoconjugates for Enhanced Intracellular Drug Delivery

Bacterial polysaccharides can be easily modified to offer dual stimuli-responsive drug delivery systems with double targeting potential. In this research work, bacterial polysaccharides hyaluronic acid (HA) were functionalized with α-tocopherol polyethylene glycol succinate (TPGS) and cholic acid (CA) to form multifunctional polysaccharides nanoconjugates (TPGS-HA-CA). Smart nanoconjugates were synthesized by forming a redox-responsive disulfide bond, and it is composed of double targeting ligands. Doxorubicin (DOX) encapsulated smart nanoconjugates were exhibited an average size of 200 nm with a uniform core-shell structure. It serves the pH-responsive side chain modulation of TPGS-HA-CA, which affords a high degree of swelling at acidic pH. Under the pH 5.0 it shows 57% of release due to the side chain modulation of C-H/N-H. Polysaccharides nanoconjugates exhibited the double stimuli-responsive drug delivery by rapid disassembly of disulfide linkage, which exhibited 72% drug release (pH 5.0+GSH 10 mM). In cytotoxic studies, DOX@TPGS-HA-CA exhibited a higher cytotoxic effect compared to DOX. Hyaluronic acid functionalization with CA, TPGS increases cell internalization, and dual stimuli activity promotes more cell death. Overall, multifunctional polysaccharides hydrogel nanoconjugates is a prospective material that has great potential for targeting breast cancer therapy.

Synthesis and Characterization of Macroinitiators Based on Polyorganophosphazenes for the Ring Opening Polymerization of N-Carboxyanhydrides

Among the various biocompatible amphiphilic copolymers, biodegradable ones are the most promising for the preparation of drug delivery systems since they are destroyed under physiological conditions, that, as a rule, reduce toxicity and provide controlled release of the drug. Hybrid graft-copolymers consisting of the main inorganic polyphosphazene chain and polypeptide side chains are of considerable interest for the development of delivery systems with a controlled degradation rate, since the main and side chains will have different degradation mechanisms (chemical and enzymatic hydrolysis, respectively). Variable particle degradation rate, controlled by the adjusting the composition of substituents, will allow selective delivery in vivo and controlled drug release. The present work proposes the preparation of biodegradable macroinitiators based on polyorganophosphazenes for the synthesis of hybrid copolymers. Synthesis of novel biodegradable macroinitiators based on polyorganophosphazenes was performed via macromolecular substitution of a polydichlorophosphazene chain with the sodium alcoholates, amines and amino acids. The composition of copolymers obtained was calculated using NMR. These polyorganophosphazenes bearing primary amino groups can be considered as convenient macroinitiators for the polymerization of NCA of α-amino acids in order to prepare hybrid copolymers polyphosphazene-graft-polypeptide. The developed macroinitiators were amphiphilic and self-assembled in the aqueous media into nanoparticles. Furthermore, the ability to encapsulate and release a model substance was demonstrated. In addition, the in vitro cytotoxicity of synthesized polymers was evaluated using two cell lines.

Gold Nanoparticles- Boon in Cancer Theranostics

BACKGROUND

Cancer is the world's second-largest cause of death, with an estimated 9.6 million fatalities in 2018. Malignant tumour (cancer) is caused by a mixture of genetic modifications due to the environmental variables that tend to activate or inactivate different genes, ultimately resulting in neoplastic transformations. Cancer is a multi-stage process that results from the conversion of the ordinary cells to tumour cells and progresses from a pre-cancer lesion to abnormal growth.

METHODS

Chemotherapy inhibits the ability of the cells to divide rapidly in an abnormal manner, but this treatment simultaneously affects the entire cellular network in the human body leading to cytotoxic effects. In this review article, the same issue has been addressed by discussing various aspects of the newer class of drugs in cancer therapeutics, i.e., Gold Nanoparticles (AuNPs) from metal nanoparticle (NP) class.

RESULTS

Metal NPs are advantageous over conventional chemotherapy as the adverse drug reactions are lesser. Additionally, ease of drug delivery, targeting and gene silencing are salient features of this treatment. Functionalized ligand-targeting metal NPs provide better energy deposition control in tumour. AuNPs are promising agents in the field of cancer treatment and are comprehensively studied as contrast agents, carriers of medicinal products, radiosensitizers and photothermal agents. For the targeted delivery of chemotherapeutic agents, AuNPs are used and also tend to enhance tumour imaging in vivo for a variety of cancer types and diseased organs.

CONCLUSION

The first part of the review focuses on various nano-carriers that are used for cancer therapy and deals with the progression of metal NPs in cancer therapy. The second part emphasizes the use of nanotechnology by considering the latest studies for diagnostic and therapeutic properties of AuNPs. AuNPs present the latest studies in the field of nanotechnology, which leads to the development of early-stage clinical trials. The next part of the review discusses the major features of five principal types of AuNPs: gold nanorods, gold nanoshells, gold nanospheres, gold nanocages, and gold nanostars that have their application in photothermal therapy (PTT).

Use of anticancer peptides as an alternative approach for targeted therapy in breast cancer: a review

Breast cancer is the most common cancer in women worldwide. Traditional therapies are expensive and cause severe side effects. Targeted therapy is a powerful method to circumvent the problems of other therapies. It also allows drugs to localize at predefined targets in a selective manner. Currently, there are several monoclonal antibodies which target breast cancer cell surface markers. However, using antibodies has some limitations. In the last two decades, many investigators have discovered peptides that may be useful to target breast cancer cells. In this article, we provide an overview on anti-breast cancer peptides, their sources and biological activities. We further discuss the pros and cons of using anticancer peptides with further emphasis on how to improve their effectiveness in cancer therapy.

Multifunctional Gold Nanoparticles: A Novel Nanomaterial for Various Medical Applications and Biological Activities

Nanotechnology has become a trending area in science and has made great advances with the development of functional, engineered nanoparticles. Various metal nanoparticles have been widely exploited for a wide range of medical applications. Among them, gold nanoparticles (AuNPs) are widely reported to guide an impressive resurgence and are highly remarkable. AuNPs, with their multiple, unique functional properties, and easy of synthesis, have attracted extensive attention. Their intrinsic features (optics, electronics, and physicochemical characteristics) can be altered by changing the characterization of the nanoparticles, such as shape, size and aspect ratio. They can be applied to a wide range of medical applications, including drug and gene delivery, photothermal therapy (PTT), photodynamic therapy (PDT) and radiation therapy (RT), diagnosis, X-ray imaging, computed tomography (CT) and other biological activities. However, to the best of our knowledge, there is no comprehensive review that summarized the applications of AuNPs in the medical field. Therefore, in this article we systematically review the methods of synthesis, the modification and characterization techniques of AuNPs, medical applications, and some biological activities of AuNPs, to provide a reference for future studies.

Multifunctionality of gold nanoparticles: Plausible and convincing properties

In a couple of decades, nanotechnology has become a trending area in science due to it covers all subject that combines diverse range of fields including but not limited to chemistry, physics and medicine. Various metal and metal oxide nanomaterials have been developed for wide range applications. However, the application of gold nanostructures and nanoparticles has been received more attention in various biomedical applications. The unique property of gold nanoparticles (AuNPs) is surface plasmon resonance (SPR) that determine the size, shape and stability. The wide surface area of AuNPs eases the proteins, peptides, oligonucleotides, and many other compounds to tether and enhance the biological activity of AuNPs. AuNPs have multifunctionality including antimicrobial, anticancer, drug and gene delivery, sensing applications and imaging. This state-of-the-art review is focused on the role of unique properties of AuNPs in multifunctionality and its various applications.

Green Nanotechnology-Driven Drug Delivery Assemblies

Green nanotechnology incorporates the principles of green chemistry and green engineering to fabricate innocuous and eco-friendly nanoassemblies to combat the problems affecting the human health or environment. Subsequently, amalgamation of green nanotechnology with drug delivery area has actually commenced a new realm of "green nanomedicine". The burgeoning demand for green nanotechnology-driven drug delivery systems has led to the development of different types of delivery devices, like inorganic (metallic) nanoparticles, quantum dots, organic polymeric nanoparticles, mesoporous silica nanoparticles, dendrimers, nanostructured lipid carriers, solid lipid nanoparticles, etc. The present article deals with a brief account of delivery devices produced from green methods and describes site-specific drug delivery systems (including their pros and cons) and their relevance in the field of green nanomedicine.

Development of cholate conjugated hybrid polymeric micelles for FXR receptor mediated effective site-specific delivery of paclitaxel

The aim of the present study was to explore the tumor targeting potential of a cholic acid (CA) conjugated polymeric micelle system for the effective delivery of paclitaxel (PTX).