Gold nanoparticles have been used in biomedical applications since their first colloidal syntheses more than three centuries ago. However, over the past two decades, their beautiful colors and unique electronic properties have also attracted tremendous attention due to their historical applications in art and ancient medicine and current applications in enhanced optoelectronics and photovoltaics. In spite of their modest alchemical beginnings, gold nanoparticles exhibit physical properties that are truly different from both small molecules and bulk materials, as well as from other nanoscale particles. Their unique combination of properties is just beginning to be fully realized in range of medical diagnostic and therapeutic applications. This critical review will provide insights into the design, synthesis, functionalization, and applications of these artificial molecules in biomedicine and discuss their tailored interactions with biological systems to achieve improved patient health. Further, we provide a survey of the rapidly expanding body of literature on this topic and argue that gold nanotechnology-enabled biomedicine is not simply an act of ‘gilding the (nanomedicinal) lily’, but that a new ‘Golden Age’ of biomedical nanotechnology is truly upon us. Moving forward, the most challenging nanoscience ahead of us will be to find new chemical and physical methods of functionalizing gold nanoparticles with compounds that can promote efficient binding, clearance, and biocompatibility and to assess their safety to other biological systems and their long-term term effects on human health and reproduction (472 references).

The golden age: gold nanoparticles for biomedicine

Nanoparticles (NPs) are increasingly used to target bacteria as an alternative to antibiotics. Nanotechnology may be particularly advantageous in treating bacterial infections. Examples include the utilization of NPs in antibacterial coatings for implantable devices and medicinal materials to prevent infection and promote wound healing, in antibiotic delivery systems to treat disease, in bacterial detection systems to generate microbial diagnostics, and in antibacterial vaccines to control bacterial infections. The antibacterial mechanisms of NPs are poorly understood, but the currently accepted mechanisms include oxidative stress induction, metal ion release, and non-oxidative mechanisms. The multiple simultaneous mechanisms of action against microbes would require multiple simultaneous gene mutations in the same bacterial cell for antibacterial resistance to develop; therefore, it is difficult for bacterial cells to become resistant to NPs. In this review, we discuss the antibacterial mechanisms of NPs against bacteria and the factors that are involved. The limitations of current research are also discussed.

/pdf/the-antimicrobial-activity-of-nanoparticles-present-455xafgyws.pdf

The antimicrobial activity of nanoparticles: present situation and prospects for the future

https://doc.rero.ch/record/29689/files/fro_apn.pdf

Antibacterial properties of nanoparticles.

Utilization of polymers as biomaterials has greatly impacted the advancement of modern medicine. Specifically, polymeric biomaterials that are biodegradable provide the significant advantage of being able to be broken down and removed after they have served their function. Applications are wide ranging with degradable polymers being used clinically as surgical sutures and implants. In order to fit functional demand, materials with desired physical, chemical, biological, biomechanical and degradation properties must be selected. Fortunately, a wide range of natural and synthetic degradable polymers has been investigated for biomedical applications with novel materials constantly being developed to meet new challenges. This review summarizes the most recent advances in the field over the past 4 years, specifically highlighting new and interesting discoveries in tissue engineering and drug delivery applications.

/pdf/biomedical-applications-of-biodegradable-polymers-2db9gcyzxw.pdf

Biomedical Applications of Biodegradable Polymers

In medicine, nanotechnology has sparked a rapidly growing interest as it promises to solve a number of issues associated with conventional therapeutic agents, including their poor water solubility (at least, for most anticancer drugs), lack of targeting capability, nonspecific distribution, systemic toxicity, and low therapeutic index. Over the past several decades, remarkable progress has been made in the development and application of engineered nanoparticles to treat cancer more effectively. For example, therapeutic agents have been integrated with nanoparticles engineered with optimal sizes, shapes, and surface properties to increase their solubility, prolong their circulation half-life, improve their biodistribution, and reduce their immunogenicity. Nanoparticles and their payloads have also been favorably delivered into tumors by taking advantage of the pathophysiological conditions, such as the enhanced permeability and retention effect, and the spatial variations in the pH value. Additionally, targeting ligands (e.g., small organic molecules, peptides, antibodies, and nucleic acids) have been added to the surface of nanoparticles to specifically target cancerous cells through selective binding to the receptors overexpressed on their surface. Furthermore, it has been demonstrated that multiple types of therapeutic drugs and/or diagnostic agents (e.g., contrast agents) could be delivered through the same carrier to enable combination therapy with a potential to overcome multidrug resistance, and real-time readout on the treatment efficacy. It is anticipated that precisely engineered nanoparticles will emerge as the next-generation platform for cancer therapy and many other biomedical applications.

Engineered Nanoparticles for Drug Delivery in Cancer Therapy

"Nanoantibiotics": a new paradigm for treating infectious diseases using nanomaterials in the antibiotics resistant era.

https://escholarship.org/content/qt55t519c0/qt55t519c0.pdf?t=o3dosu

"Combo" nanomedicine: Co-delivery of multi-modal therapeutics for efficient, targeted, and safe cancer therapy

Stimuli-responsive polymers and nanomaterials for gene delivery and imaging applications ☆

RNA interference (RNAi) has been regarded as a revolutionary tool for manipulating target biological processes as well as an emerging and promising therapeutic strategy. In contrast to the tangible and obvious effectiveness of RNAi in vitro, silencing target gene expression in vivo using small interfering RNA (siRNA) has been a very challenging task due to multiscale barriers, including rapid excretion, low stability in blood serum, nonspecific accumulation in tissues, poor cellular uptake and inefficient intracellular release. This minireview introduces major challenges in achieving efficient siRNA delivery in vivo and discusses recent advances in overcoming them using chemically modified siRNA, viral siRNA vectors and nonviral siRNA carriers. Enhanced specificity and efficiency of RNAi in vivo via selective accumulations in desired tissues, specific binding to target cells and facilitated intracellular trafficking are also commonly attempted utilizing targeting moieties, cell-penetrating peptides, fusogenic peptides and stimuli-responsive polymers. Overall, the crucial roles of the interdisciplinary approaches to optimizing RNAi in vivo, by efficiently and specifically delivering siRNA to target tissues and cells, are highlighted.

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1742-4658.2010.07904.x

Young Jik Kwon

Papers

"Nanoantibiotics": a new paradigm for treating infectious diseases using nanomaterials in the antibiotics resistant era.

"Combo" nanomedicine: Co-delivery of multi-modal therapeutics for efficient, targeted, and safe cancer therapy

Stimuli-responsive polymers and nanomaterials for gene delivery and imaging applications ☆

Efficient and targeted delivery of siRNA in vivo.

Molecular genetics and emerging therapies for retinitis pigmentosa: Basic research and clinical perspectives