Recent Patents on Nanomedicine - Volume 3, Issue 1, 2013

Prosthetic devices in dentistry are commonly made of acrylic resin. This material has been continuously improved and nanotechnology is now an important part of the process. The main objective of dentures is their restorative function, while preventing the adherence of microorganisms present in the oral mucosa. Recently, nanopigments, fibers and silver nanoparticles were incorporated into poly(methyl methacrylate) formulations, thus obtaining dental materials with a reduced porosity, increased flexural strength and showing a lower Candida albicans adherence. The modified acrylic resin was subjected to in vitro cytotoxicity and genotoxicity tests, resulting in a biocompatible option for denture bases. The history, challenges, innovations and recent patents based on nanoparticles in prosthetic materials for dentures are reviewed in this paper.

We live in a world of convergence where scientific techniques from a variety of seemingly disparate fields are being applied cohesively to the study and solution of biomedical problems. For instance, the semiconductor processing field has been primarily developed to cater to the needs of the ever decreasing transistor size and cost while increasing functionality of electronic circuits. In recent years, pioneers in this field have equipped themselves with a powerful understanding of how the same techniques can be applied in the biomedical field to develop new and efficient systems for the diagnosis, analysis and treatment of various conditions in the human body. In this paper, we review the major inventions and experimental methods which have been developed for nano/micro fluidic channels, nanoparticles fabricated by top-down methods, and in-vivo nanoporous microcages for effective drug delivery. This paper focuses on the information contained in patents as well as the corresponding technical publications. The goal of the paper is to help emerging scientists understand and improvise over these inventions.

The use of nanocarriers as drug delivery vehicles for chemotherapeutics improves overall pharmacokinetics and biodistribution of otherwise unencapsulated cytotoxic agents, and can significantly decrease unintended negative sideeffects commonly associated with these types of drugs. While a wide variety of nanocarrier-based chemotherapeutics have been reported, micelles are particularly attractive candidates due to inherent characteristics that make them ideal for drug encapsulation. Therefore, it is not surprising that several formulations are currently in various stages of clinical trials. However, while proving to be quite promising, challenges remain involving effective drug transfer from the nanocarrier to cancer cells. Thus, several groups have reported various strategies involving modifications made to these drug delivery vehicles in order to improve delivery of encapsulated cytotoxic agents to tumor cells. While various methods have been reported to achieve this, here we focus specifically on modifications made involving targeting ligand addition, as well as the incorporation of pH-sensitive molecules to these nanocarriers. Recent patents involving these specific modifications made to traditional micelles are discussed in this review.

Gliomas amount to about 45% of all primary CNS tumors and 77% of all are malignant primary CNS tumors. They develop from diverse histological lineages, including oligodendrogliomas, astrocytoma and mixed oligoastrocytoma. The efficacy of current multimodal therapeutic strategies in gliomas is limited by the lack of specific therapies against malignant cells, and the prognosis in patients affected by primary brain tumors is still very unfavorable. Glial tumors seem to be able to create a favorable environment for the invasion of neoplastic cells when they combine with the extracellular matrix via cell surface receptors. The major problem in brain drug delivery is the presence of the blood brain barrier which limits the delivery of many chemotherapeutic agents and other kinds of therapeutic molecules. This event often contributes to the failure of treatment. Nanoparticle systems can represent ideal devices for delivery of specific compounds to brain tumors across the blood brain barrier. In this review we will focus on the blood brain barrier role and possibilities of its therapeutic overcoming, on mechanisms of angiogenesis into gliomas, their importance into tumor progression and the possibilities to block these mechanisms with new nanoparticle-based therapeutic strategies. Relevant patents of nanoparticle systems used as drug delivery carriers in brain tumor treatment are also reported.

Numerous scientific efforts have been made till date to provide an efficient ocular drug delivery system, but still it is challenging for pharmaceutical scientists. Most of the ocular diseases are treated by topical drug application in the form of suspensions, solutions and ointments. But because of various anatomical and pathophysiological barriers prevailing in the eye, these conventional dosage forms suffer from the problem of poor ocular bioavailability. Nanotechnology emerges not only as a potential tool for ocular drug delivery but also as a solution to drug targeting and improved bioavailability including various solubility related problems, This review provides an overview of various limitations associated with ocular drug delivery, summarizes recent findings and patents on various nanotechnology products in ocular drug delivery.

Microfluidics has emerged as a novel platform for a diverse array of actual and potential applications ranging from drug delivery, point-of-care diagnostic chips, to microreactors. Recent developments on microfabrication techniques have opened the door to particle synthesis with precise control over the shapes, morphologies, and size distributions. This paper presents the recent patents on microfluidic strategies for the production of particles, such as core-shell particles, Janus particles (two-component or three-component) and non-spherical particles (ellipsoidal, discoid, rod). Advances in the design of relevant microfluidic chips, fabrication process, and techniques for assembling component, are converging towards biomedical applications of droplet-based microfluidic technologies

Because of the increasing number of cases of mycosis that are resistant to treatment and the incidence of fungal infections, there is an urgent need to develop new and efficient drugs for antifungal therapies. Because the development of new drugs is expensive and time consuming, one strategy is the use of nanotechnology for drug delivery systems to prolong the use of the currently available antifungal agents. Several efforts are being expended to achieve these goals. In this review, some examples of patents filed that claim the development of nanostructured drugs, primarily through the use of liposomes, polymeric nanoparticles and nanomaterials that possess antimicrobial activity, are presented. In addition to the presented examples, there are many possibilities to be explored in this field for developing new treatment choices to prevent and even to cure important global diseases, such as mycosis.

Recently, natural products are attaining a global interest as potential drug candidates due to better tolerance and minimum adverse drug reactions as compared to synthetic molecules. According to WHO estimation, about three-quarters of the world's population is consuming herbal products for various diseases including cancer, diabetes, human immunodeficiency, asthma and cardiovascular disorders. Various active ingredients are extracted from the herbs and formulated in different modern dosage forms, such as tablets, capsules, topical cream, gel, ointment and even some novel drug delivery forms, like extended release, sustained release, and microcapsule dosage forms. Therefore, patent filing of herbal formulations has increased over the past few years and scientific evidence of therapeutic activity has been reported by performing various in vitro and in vivo experiments. This manuscript deals with various patented herbal formulations of rutin and quercetin alone or in combination with other natural ingredients for various therapeutic activities such as antioxidant, antiviral, anti- inflammatory, anticancer, oedema and cardiovascular disorders. These formulations are available in various conventional dosage forms like tablet, capsule, troche, cream and syrups.