ABSTRACT
Biological materials are a rich resource for nanoscale engineering. Their structure is easily accessible via their DNA and they were optimised through evolution to fulfill their function.
Subject(s)
Capsid/chemistry , DNA/genetics , Genetic Engineering/methods , Nanoparticles/virology , Nanotechnology/methods , Viruses/chemistry , Biocompatible Materials/chemical synthesis , Biocompatible Materials/pharmacology , Biological Control Agents/chemistry , Biological Control Agents/metabolism , Capsid/metabolism , Capsid/ultrastructure , DNA/metabolism , Drug Delivery Systems/methods , Gene Transfer Techniques/trends , Humans , Molecular Mimicry , Nanoparticles/metabolism , Nanoparticles/supply & distribution , Nanoparticles/ultrastructure , Viruses/metabolism , Viruses/ultrastructureABSTRACT
Electrospinning and electrospraying are versatile techniques for the production of nano- to micro-scale fibers and particles. Over the past 2 decades, significant progresses have been made to advance the fundamental understandings of these electrohydrodynamic processes. Researchers have investigated different polymeric and non-polymeric substrates for producing submicron electrospun/electrosprayed materials of unique morphologies and physicochemical properties. This chapter provides an overview on the basic principles of electrospinning and electrospraying, highlighting the effects of key processing and solution parameters. Electrohydrodynamic phenomena of edible substrates, including polysaccharides (xanthan, alginate, starch, cyclodextrin, pullulan, dextran, modified celluloses, and chitosan), proteins (zein, what gluten, whey protein, soy protein, gelatin, etc.), and phospholipids are reviewed. Selected examples are presented on how ultrafine fibers and particles derived from these substrates are being exploited for food and nutraceutical applications. Finally, the challenges and opportunities of the electrostatic methods are discussed.
Subject(s)
Food Technology/methods , Nanofibers/supply & distribution , Nanoparticles/supply & distribution , Nanofibers/chemistry , Nanoparticles/chemistry , Static ElectricityABSTRACT
Nanoparticles exhibit size-dependent properties which make size-selective purification of proteins, DNA or synthetic nanoparticles essential for bio-analytics, clinical medicine, nano-plasmonics and nano-material sciences. Current purification methods of centrifugation, column chromatography and continuous-flow techniques suffer from particle aggregation, multi-stage process, complex setups and necessary nanofabrication. These increase process costs and time, reduce efficiency and limit dynamic range. Here, we achieve an unprecedented real-time nanoparticle separation (51-1500 nm) using a large-pore (2 µm) deterministic lateral displacement (DLD) device. No external force fields or nanofabrication are required. Instead, we investigated innate long-range electrostatic influences on nanoparticles within a fluid medium at different NaCl ionic concentrations. In this study we account for the electrostatic forces beyond Debye length and showed that they cannot be assumed as negligible especially for precise nanoparticle separation methods such as DLD. Our findings have enabled us to develop a model to simultaneously quantify and modulate the electrostatic force interactions between nanoparticle and micropore. By simply controlling buffer solutions, we achieve dynamic nanoparticle size separation on a single device with a rapid response time (<20 s) and an enlarged dynamic range (>1200%), outperforming standard benchtop centrifuge systems. This novel method and model combines device simplicity, isolation precision and dynamic flexibility, opening opportunities for high-throughput applications in nano-separation for industrial and biological applications.
