Muthu Vignesh Vellayappan

Tangible nanocomposites with diverse properties for heart valve application

Abstract Cardiovascular disease claims millions of lives every year throughout the world. Biomaterials are used widely for the treatment of this fatal disease. With the advent of nanotechnology, the use of nanocomposites has become almost inevitable in the field of biomaterials. The versatile properties of nanocomposites, such as improved durability and biocompatibility, make them an ideal choice for various biomedical applications. Among the various nanocomposites, polyhedral oligomeric silsesquioxane-poly(carbonate-urea)urethane, bacterial cellulose with polyvinyl alcohol, carbon nanotubes, graphene oxide and nano-hydroxyapatite nanocomposites have gained popularity as putative choices for biomaterials in cardiovascular applications owing to their superior properties. In this review, various studies performed utilizing these nanocomposites for improving the mechanical strength, anti-calcification potential and hemocompatibility of heart valves are reviewed and summarized. The primary motive of this work is to shed light on the emerging nanocomposites for heart valve applications. Furthermore, we aim to promote the prospects of these nanocomposites in the campaign against cardiovascular diseases.

An insight on electrospun-nanofibers-inspired modern drug delivery system in the treatment of deadly cancers

In spite of ample researches and admirable achievements, there are still a significant number of deaths happening every year due to cancer. Furthermore, the number of new cases recorded is also not reduced despite the advent of various preventive measures. Though current clinical approaches yield commendable results, they elicit severe systemic side-effects and also fail to avoid the recurrence of the disease. To address these issues, nanotechnology-empowered modern drug delivery systems showcase excellent properties for the targeting and controlled delivery of biomolecules over a period of time. In the past decade, the materials-based cancer research field has witnessed the exploration of several attractive drug delivery approaches for the administration of synthetic drugs to genetic materials. Among those, the electrospinning-based nanofibrous mesh has attracted several works on treating common deadly cancers such as those of the lung, breast and colon. The capability of nanofibers to enable increased drug loading, maintenance of significant bioactivity, excellent drug encapsulation, controlled and targeted delivery, has helped the researchers to achieve successful administration of a variety of anti-cancer agents. This review gives an insight into the process of electrospinning, its essential parameters, the types of drug incorporation and the works reported on common deadly cancers. Moreover, the future direction of this effective alternative is also delineated, making electrospun nanofibers as a suitable vehicle for delivering drugs to the cancer sites.

Carbon nanotubes and graphene as emerging candidates in neuroregeneration and neurodrug delivery

Neuroregeneration is the regrowth or repair of nervous tissues, cells, or cell products involved in neurodegeneration and inflammatory diseases of the nervous system like Alzheimer’s disease and Parkinson’s disease. Nowadays, application of nanotechnology is commonly used in developing nanomedicines to advance pharmacokinetics and drug delivery exclusively for central nervous system pathologies. In addition, nanomedical advances are leading to therapies that disrupt disarranged protein aggregation in the central nervous system, deliver functional neuroprotective growth factors, and change the oxidative stress and excitotoxicity of affected neural tissues to regenerate the damaged neurons. Carbon nanotubes and graphene are allotropes of carbon that have been exploited by researchers because of their excellent physical properties and their ability to interface with neurons and neuronal circuits. This review describes the role of carbon nanotubes and graphene in neuroregeneration. In the future, it is hoped that the benefits of nanotechnologies will outweigh their risks, and that the next decade will present huge scope for developing and delivering technologies in the field of neuroscience.

Review: Radiation-induced surface modification of polymers for biomaterial application

The field of biomaterials is one of the fast growing and continuously dominating in medical arena for the last five decades. Biomaterials utilize various kinds of materials ranging from metals, polymers, ceramics and biological substances as an alternative for replacing/assisting the functions of different parts of human system. Major issues associated with biomaterials are their properties and the biocompatibility which have to be addressed and resolved before promoting it to the market or clinical setting. In this scenario, polymers have emerged as a better candidate with versatile properties that make them ideal choice for biomedical applications. However, still the problem of biocompatibility limits the use of polymers in the human body. Several surface modification strategies are continuously evolving to improve the biocompatibility of polymers. This review initially outlines the polymers’ biomedical applications and also elicits the immune aspects of biocompatibility. Further, a thorough attempt is made to summarize the radiation-induced surface modification of the polymers. This review will help us to keep abreast of the recent advances in the radiation-induced surface modification and also in promoting radiation as a probable candidate to enhance the biocompatibility of polymers.

Review: physico-chemical modification as a versatile strategy for the biocompatibility enhancement of biomaterials

A biomaterial can be defined as a material intended to interface with biological systems to evaluate, treat, augment or replace any tissue, organ or function of the body. Major problems associated with biomaterials are their properties and biocompatibility, which need to be tackled and resolved before promoting a particular biomaterial to the market or implanting it into a biological system. To enhance the biocompatibility of the biomaterials, several surface modification strategies, such as physico-chemical, mechanical and biological modifications, have been explored. In this review, some recent applications of physico-chemical modification technologies, such as alteration in the structure of a molecule by chemical modification, surface grafting, abrasive blasting and acid etching, surface coatings, heat and steam treatment for medical materials such as polymers, metals, ceramics and nanocomposites are discussed. This article will promote physico-chemical modification as a versatile technology in surface engineering to improve the properties and biocompatibility of medical materials. Furthermore, it will instigate the growth of the biomaterial market with various high quality biomaterials.

Gallic acid: Prospects and molecular mechanisms of its anticancer activity

Cancer is the second leading cause of death worldwide. There is always a huge demand for novel anticancer drugs and scientists explore various natural and artificial compounds to overcome this. Gallic acid (GA) is one of the phenolic acids found in many dietary substances and herbs used in ancient medicine. It possesses antiinflammatory, antioxidant, antiviral and antibacterial properties. The present review summarizes the anticancer activity of GA and its derivatives. Various in vitro and in vivo experiments of GA against a variety of cancer cell lines were reported. The previous studies show that the anticancer activity of GA is related to the induction of apoptosis through different mechanisms like generation of reactive oxygen species (ROS), regulation of apoptotic and anti-apoptotic proteins, suppression and promotion of oncogenes, inhibition of matrix metalloproteinases (MMPs) and cell cycle arrest depending upon the type of cancer investigated. Conclusively, GA and its derivatives may be considered as a potent drug for cancer treatment alone as well as in combination with other anticancer drugs to increase the efficiency of chemotherapy. However, there is still a need for more experimentation in knock-out animal models and human clinical trials to promote and place GA and its derivatives on the commercial market.

Chemopreventive effect of apple and berry fruits against colon cancer

Colon cancer arises due to the conversion of precancerous polyps (benign) found in the inner lining of the colon. Prevention is better than cure, and this is very true with respect to colon cancer. Various epidemiologic studies have linked colorectal cancer with food intake. Apple and berry juices are widely consumed among various ethnicities because of their nutritious values. In this review article, chemopreventive effects of these fruit juices against colon cancer are discussed. Studies dealing with bioavailability, in vitro and in vivo effects of apple and berry juices are emphasized in this article. A thorough literature survey indicated that various phenolic phytochemicals present in these fruit juices have the innate potential to inhibit colon cancer cell lines. This review proposes the need for more preclinical evidence for the effects of fruit juices against different colon cancer cells, and also strives to facilitate clinical studies using these juices in humans in large trials. The conclusion of the review is that these apple and berry juices will be possible candidates in the campaign against colon cancer.

Electrospinning applications from diagnosis to treatment of diabetes

Electrospinning is a facile, yet low cost and reproducible technique that can use both natural and synthetic polymers to address problems in diagnosis and treatment of diabetes. For the diagnosis of diabetes, effective continuous glucose monitoring of the blood glucose level can be achieved by using electrospun glucose biosensors. Electrospun nanofibers confer a high-surface area, micro-porosity, and potential to encapsulate drugs or biomolecules within nanofibers. Even though electrospinning has been used widely there is no review available till now with the applications of electrospinning specifically for the diagnosis and treatment of diabetes. In this critical review, recent advances of electrospinning to optimize the glucose sensing ability and a myriad of diabetic drug delivery techniques via electrospinning are discussed. Future perspectives of biodegradable nanofibers are also discussed in the last section, which highlights the current challenges, innovation and development of novel electrospun nanofibers for theranostics targeted to diabetics.

Nanomaterials as a game changer in the management and treatment of diabetic foot ulcers

Nanoengineered biomaterials have tremendously improved the range of tools utilized for the control of as well as acceleration of healing of diabetic foot ulcers (DFU) over the last few decades. Despite nanoparticles and electrospun nanofibers being used extensively for the treatment of DFU, there has been no review available till now which addresses the utilization of the latest nanodelivery techniques along with modern electrospun nanofiber treatments for DFU. This review thoroughly summarizes the latest mindboggling findings of potential nanomaterials like polymeric and metallic nanoparticles and electrospun nanofibers for DFU treatment. In addition, a succinct insight into the potential of the aforementioned nanomaterials which can be exploited as therapeutic delivery agents for improving the regeneration of damaged dermal and epidermal tissues of DFU is underscored. Ultimately, current challenges and future prospects of nanoparticles and electrospun nanofibers for DFU treatment are highlighted.

Multifaceted prospects of nanocomposites for cardiovascular grafts and stents

Cardiovascular disease is the leading cause of death across the globe. The use of synthetic materials is indispensable in the treatment of cardiovascular disease. Major drawbacks related to the use of biomaterials are their mechanical properties and biocompatibility, and these have to be circumvented before promoting the material to the market or clinical setting. Revolutionary advancements in nanotechnology have introduced a novel class of materials called nanocomposites which have superior properties for biomedical applications. Recently, there has been a widespread recognition of the nanocomposites utilizing polyhedral oligomeric silsesquioxane, bacterial cellulose, silk fibroin, iron oxide magnetic nanoparticles, and carbon nanotubes in cardiovascular grafts and stents. The unique characteristics of these nanocomposites have led to the development of a wide range of nanostructured copolymers with appreciably enhanced properties, such as improved mechanical, chemical, and physical characteristics suitable for cardiovascular implants. The incorporation of advanced nanocomposite materials in cardiovascular grafts and stents improves hemocompatibility, enhances antithrombogenicity, improves mechanical and surface properties, and decreases the microbial response to the cardiovascular implants. A thorough attempt is made to summarize the various applications of nanocomposites for cardiovascular graft and stent applications. This review will highlight the recent advances in nanocomposites and also address the need of future research in promoting nanocomposites as plausible candidates in a campaign against cardiovascular disease.