Current Organic Chemistry - Volume 18, Issue 2, 2014

The use of polymers in different fields of modern medicine has generated significant advances in tissue engineering, diagnostic and therapeutic strategies. Polymers have been used to control the rate of drug release, prevent toxicity, protect drugs from degradation before delivery, target drugs to the site of action, improve absorption, bioavailability and therapeutic efficacy. Although synthetic polymers allow producing tailor-made materials, however natural polymers exhibit the advantages of excellent biodegradability, biocompatibility, cost-effectiveness and environmental friendliness. This review presents the current status of research and clinical applications of natural polymers as drug delivery systems for different administration routes.

The past decade has witnessed the development of innovative biosensing technologies for detecting pathogens, and evaluating the anti-microbial susceptibility test in the infectious diseases. Recent advances in the field have been focused on the development of miniaturized biosensors with high sensitivity, specificity and stability. Possibility for commercialization is also a key criterion to develop biosensors in reality. In this article, we introduced several electrical-based biosensors with prospective for commercialization. To have an in-field detection for pathogens, the electrical biosensor is promising because of its ease to be implemented with micro/nano fabrication technologies. Several electrical biosensing techniques, such as ion-sensitive field effect transistor, nanowire, and microcantilever have been introduced. In addition, advantages and achievements of each electrical biosensing technique have also been reviewed.

Silver is a well known antimicrobial agent against a wide range of microorganisms – over 650 microorganisms from different classes, such as gram-positive and gram-negative bacteria, fungi or viruses. Due to the ratio between positive and negative (side) effects, silver gained advantages over many other antimicrobial agents, and especially antibiotics. The potential applications of silver nanoparticles (Ag-NPs) are strongly influenced by some factors such as size and shape. Besides the huge efforts in the field of synthesis, characterization and applications of Ag-NPs there are many unknown or contradictory observations/conclusions. The current review is focused on the synthesis and characterization of silver for biomedical applications and point out the correlations between the characteristics of Ag-NPs (size and shape, especially) and their induced effects.

As traditional antimicrobial approaches become less effective, novel alternatives in treating resistant infections are required. Nanotechnology is an emerging field recently exploited for its numerous biomedical applications. Magnetic nanoparticles has proved their anti-microbial properties when used as drug delivery systems and recent proclivity propose Fe3O4 derived nanosystems as efficient anti-biofilm development indicators. This paper discusses the most recent findings regarding the usage of magnetic nanoparticles as potent drug delivery shuttles in anti-microbial approaches.

Metal oxide nanoparticles represent a new class of important materials that are increasingly being developed for use in research and health-related applications. Although the in vitro antibacterial activity of zinc oxides and some other zinc compounds has been known for quite some time, only in the last few years nanoparticles of ZnO have been investigated for their antibacterial activity, the knowledge about it remaining deficient. The antimicrobial activity of ZnO nanoparticles is strongly influenced by some factors such as size and the presence of light. The potential applications include, but are not limited to, topic drugs, cosmetics or component for agents that control the spread of bacterial strains (antibacterial paint in hospitals, antibacterial coatings for fabrics, antibacterial packaging for food, etc). The current review aims to present the level of knowledge accumulated on the antibacterial and antifungal activity of ZnO.

Although molecular medicine has developed numerous antimicrobial drugs to kill or inhibit microbes, many infectious diseases remain difficult to treat because of challenges, such as intracellular infections, acquired resistance, and adverse side effects. Nanotechnology has made significant progress over the past decades and is introducing a new paradigm in pharmacotherapy. Nanoparticles have many unique physicochemical properties with promising solutions for the problems with conventional antimicrobial agents. The potency and efficacy of an antimicrobial agent and/or the target specificity of a drug can be greatly enhanced by applying nanoparticle technology. Significant evidence has demonstrated that nanoparticles can be effective in treating microbes and acquired resistance. This study reviewed the latest advances in using nanoparticles for antimicrobial activities, and for the delivery of antimicrobial drugs.

Secosteroids are an important group of modified steroids, which exhibits a variety of different biological activities. Studies on secosteroids have shown that modifications of the rigid tetracyclic steroidal carbon skeleton by cleavage of the internal C-C bonds provides more flexible compounds with new biological properties. The search for steroid compounds analogs with improved biological properties includes ring transformation into seco system. The recent development in the partial syntheses of secosteroids is described herein, as well as studies of methods for modifications of such molecules.

β-Amino ketones are of increasing interest owing to their utility as important synthetic precursors in the synthesis of bioactive molecules and natural products. As a result numerous syntheses of β-amino ketones have emerged in recent years. Of particular significance are those methods that allow access to stereopure β-amino ketones. This review highlights recent advances in stereoselective syntheses of β-amino ketones and also illustrates the importance of β-amino ketones as useful synthons.