The use of polymeric nanocarriers to transport active compounds like small-molecular drugs, peptides, or genes found an increased attention throughout the different fields of natural sciences. Not ...only that these nanocarriers enhance the properties of already existing drugs in terms of solubility, bioavailability, and prolonged circulation times, furthermore they can be tailor-made in such a manner that they selectively release their cargo at the desired site of action. For the triggered release, these so-called smart drug delivery systems are designed to react on certain stimuli like pH, temperature, redox potential, enzymes, light, and ultrasound. Some of these stimuli are naturally occurring in vivo, for example the difference in pH in different cellular compartments while others are caused by the disease, which is to be treated, like differences in pH and temperature in some tumor tissues. Other external applied stimuli, like light and ultrasound, allow the temporal and spatial control of the release, since they are not triggered by any biological event. This review gives a brief overview about some types of stimuli-responsive nanocarriers with the main focus on organic polymer-based systems. Furthermore, the different stimuli and the design of corresponding responsive nanocarriers will be discussed with the help of selected examples from the literature.
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Functional graphene nanomaterials (FGNs) are fast emerging materials with extremely unique physical and chemical properties and physiological ability to interfere and/or interact with bioorganisms; ...as a result, FGNs present manifold possibilities for diverse biological applications. Beyond their use in drug/gene delivery, phototherapy, and bioimaging, recent studies have revealed that FGNs can significantly promote interfacial biointeractions, in particular, with proteins, mammalian cells/stem cells, and microbials. FGNs can adsorb and concentrate nutrition factors including proteins from physiological media. This accelerates the formation of extracellular matrix, which eventually promotes cell colonization by providing a more beneficial microenvironment for cell adhesion and growth. Furthermore, FGNs can also interact with cocultured cells by physical or chemical stimulation, which significantly mediate their cellular signaling and biological performance. In this review, we elucidate FGNs-bioorganism interactions and summarize recent advancements on designing FGN-based two-dimensional and three-dimensional architectures as multifunctional biological platforms. We have also discussed the representative biological applications regarding these FGN-based bioactive architectures. Furthermore, the future perspectives and emerging challenges will also be highlighted. Due to the lack of comprehensive reviews in this emerging field, this review may catch great interest and inspire many new opportunities across a broad range of disciplines.
Interfacial multivalent interactions at pathogen-cell interfaces can be competitively inhibited by multivalent scaffolds that prevent pathogen adhesion to the cells during the initial stages of ...infection. The lack of understanding of complex biological systems makes the design of an efficient multivalent inhibitor a toilsome task. Therefore, we have highlighted the main issues and concerns associated with blocking pathogen at interfaces, which are dependent on the nature and properties of both multivalent inhibitors and pathogens, such as viruses and bacteria. The challenges associated with different cores or carrier scaffolds of multivalent inhibitors are concisely discussed with selected examples.
Polymer therapeutics encompass polymer–protein conjugates, drug–polymer conjugates, and supramolecular drug‐delivery systems. Numerous polymer–protein conjugates with improved stability and ...pharmacokinetic properties have been developed, for example, by anchoring enzymes or biologically relevant proteins to polyethylene glycol components (PEGylation). Several polymer–protein conjugates have received market approval, for example the PEGylated form of adenosine deaminase. Coupling low‐molecular‐weight anticancer drugs to high‐molecular‐weight polymers through a cleavable linker is an effective method for improving the therapeutic index of clinically established agents, and the first candidates have been evaluated in clinical trials, including, N‐(2‐hydroxypropyl)methacrylamide conjugates of doxorubicin, camptothecin, paclitaxel, and platinum(II) complexes. Another class of polymer therapeutics are drug‐delivery systems based on well‐defined multivalent and dendritic polymers. These include polyanionic polymers for the inhibition of virus attachment, polycationic complexes with DNA or RNA (polyplexes), and dendritic core–shell architectures for the encapsulation of drugs. In this Review an overview of polymer therapeutics is presented with a focus on concepts and examples that characterize the salient features of the drug‐delivery systems.
Thirty years ago polymeric carriers were first suggested as covalent drug‐delivery vehicles. Polymer therapeutics has now emerged as an exciting field of research for improving the therapeutic potential of low‐molecular‐weight drugs, proteins, and oligonucleotides. Polymer‐based therapeutics have enhanced stability as well as longer circulation in the blood, and several special effects, such as tumor selectivity and multivalent interactions, can now be tailored.
The topographic features of an implant, which mechanically regulate cell behaviors and functions, are critical for the clinical success in tissue regeneration. How cells sense and respond to the ...topographical cues, e.g., interfacial roughness, is yet to be fully understood and even debatable. Here, the mechanotransduction and fate determination of human mesenchymal stem cells (MSCs) on surface roughness gradients are systematically studied. The broad range of topographical scales and high‐throughput imaging is achieved based on a catecholic polyglycerol coating fabricated by a one‐step‐tilted dip‐coating approach. It is revealed that the adhesion of MSCs is biphasically regulated by interfacial roughness. The cell mechanotransduction is investigated from focal adhesion to transcriptional activity, which explains that cellular response to interfacial roughness undergoes a direct force‐dependent mechanism. Moreover, the optimized roughness for promoting cell fate specification is explored.
Roughness gradient surfaces covering a wide range of roughness from nanometer to micrometer are designed to explore the mechanism of topography‐specific responses of stem cells. The adhesion of cells is biphasically regulated by interfacial roughness in a direct force‐dependent mechanism, which enables exploration of the optimized roughness range for promoting osteogenic differentiation or phenotype maintenance of the stem cells.
The application of nanotechnology in medicine and pharmaceuticals is a rapidly advancing field that is quickly gaining acceptance and recognition as an independent area of research called ...“nanomedicine”. Urgent needs in this field, however, are biocompatible and bioactive materials for antifouling surfaces and nanoparticles for drug delivery. Therefore, extensive attention has been given to the design and development of new macromolecular structures. Among the various polymeric architectures, dendritic (“treelike”) polymers have experienced an exponential development due to their highly branched, multifunctional, and well‐defined structures. This Review describes the diverse syntheses and biomedical applications of dendritic polyglycerols (PGs). These polymers exhibit good chemical stability and inertness under biological conditions and are highly biocompatible. Oligoglycerols and their fatty acid esters are FDA‐approved and are already being used in a variety of consumer applications, e.g., cosmetics and toiletries, food industries, cleaning and softening agents, pharmaceuticals, polymers and polymer additives, printing photographing materials, and electronics. Herein, we present the current status of dendritic PGs as functional dendritic architectures with particular focus on their application in nanomedicine, in drug, dye, and gene delivery, as well as in regenerative medicine in the form of non‐fouling surfaces and matrix materials.
The current status of dendritic polyglycerols as functional dendritic architectures with particular focus on their biomedical applications is described in this Review. Drug, dye, and gene delivery for nanomedicine as well as non‐fouling surfaces and matrix materials for regenerative medicine are highlighted as potential application areas.
Detergents enable the purification of membrane proteins and are indispensable reagents in structural biology. Even though a large variety of detergents have been developed in the last century, the ...challenge remains to identify guidelines that allow fine-tuning of detergents for individual applications in membrane protein research. Addressing this challenge, here we introduce the family of oligoglycerol detergents (OGDs). Native mass spectrometry (MS) reveals that the modular OGD architecture offers the ability to control protein purification and to preserve interactions with native membrane lipids during purification. In addition to a broad range of bacterial membrane proteins, OGDs also enable the purification and analysis of a functional G-protein coupled receptor (GPCR). Moreover, given the modular design of these detergents, we anticipate fine-tuning of their properties for specific applications in structural biology. Seen from a broader perspective, this represents a significant advance for the investigation of membrane proteins and their interactions with lipids.
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