Recent Advancements in Aptamer-bioconjugates: Sharpening Stones for Breast and Prostate Cancers Targeting

Breast and prostate cancers are common types of cancers with various strategies, such as chemotherapy and radiotherapy, for their therapy. Since these methods have undesired side effects and poor target affinity, neoteric strategies—known as aptamer-based smart drug delivery systems (SDDSs)—have been developed in recent years to overcome the obstacles of current treatment, and investigated for a clinical trial. The high affinity and versatility of aptamers for binding to the corresponding targets make them highly noticeable agents in the drug delivery domains. In addition to their exceptional benefits, aptamers are able to overcome tumor resistance because of their high selectivity and low toxicity. Furthermore, aptamers can conjugate with various drugs, nanoparticles and antibodies and effectively deliver them to the specific breast and prostate cells. This review highlights the current researches in aptamer-conjugate developments for targeting breast and prostate cancers, with the special focus on the nanoparticle-aptamer bioconjugates, systematic evolution of ligands by exponential enrichment (SELEX) system and SDDS, especially cutting-edge articles from 2008 to present. Finally, the future prospects and challenges are described

Deep eutectic solvents: cutting-edge applications in cross-coupling reactions

Deep eutectic solvents (DESs), surmised as “the organic reaction medium of the century”, have reverberated a new symphony throughout the present green millennium. A brief historical account of the DES systems and their physicochemical properties as task-specific and designer solvents for cross-coupling reactions are appraised including the hole theory that explains the underlying mechanistic pathway for this emerging neoteric medium. The insights into cross-coupling reactions and their applications are included, highlighting the significant achievements pertaining to the dual role of DESs as a solvent and catalyst. In addition, popular “name-reactions” for the carbon–carbon and carbon–heteroatom bond formations related to the nature of DESs and the core optimum conditions are included. The review also encompasses the novel approaches to privileged catalytic systems and identify the voids left in cross-coupling reactions where DES systems have not made inroads yet. Finally, the challenges of utilizing the neoteric derivatives of DES for these reactions are expounded.S. E. H. and R. A. are grateful to the Iran Science Elites Federation (ISEF). D. J. R. gratefully acknowledges financial support from the Spanish Ministerio de Economía, Industria y Competitividad (PGC2018-096616-B-100) and University of Alicante (VIGROB-316FI)

Polymeric Nanoparticles for Nasal Drug Delivery to the Brain: Relevance to Alzheimer\u27s Disease

Currently, Alzheimer\u27s disease (AD) accounts for more than half of all dementia cases. Although genetics, age, and environmental factors affect the disease, the cause of AD is not yet fully known. Various drugs have been proposed for the prevention and treatment of AD, but the delivery of these therapeutic agents to the brain is difficult. The blood–brain barrier prevents systemic drugs from accessing the central nervous system and designing a suitable system to overcome this barrier has attracted much attention. The intranasal pathway, given its proximity to the brain, provides a great opportunity for drug delivery. Understanding the physiological characteristics of the nose can be useful in selecting the appropriate carrier and material. Some of the emerging vehicles used for nose-to-brain delivery of anti-AD drugs are natural (such as chitosan) and polymeric (such as poly(lactic-co-glycolic acid) and polyethylene glycol) nanoparticles (NPs). This review discusses the hypotheses for AD pathogenesis and highlights recent advances in the applications of natural and polymeric NPs for treatment. The fundamental and applied aspects of this approach for nasal drug delivery to the brain are reviewed here with thoughts on what is needed for the field to mature also provided