Supramolecular systems for bioapplications:recent research progress in China

Supramolecular systems feature dynamic,reversible and stimuli-responsive characteristics,which are not easily achieved by molecular entities.The last decade has witnessed tremendous advances in the investigations of supramolecular systems for various bioapplications,which include drug delivery,anticancer therapy,antibacterial therapy,photodynamic therapy,photothermal therapy,combination therapy,antidotes for residual drugs or toxins,and bioimaging and biosensing.Host-guest chemistry has played a key role in the development of such bioactive supramolecular systems,and natural macrocycles(such as cyclodextrins),synthetic macrocycles(such as calixarenes,cucurbit[n]urils,and pillararenes),and porous framework polymers(such as supramolecular organic frameworks and flexible organic frameworks)have been most successfully used as hosts to build different kinds of host-guest systems for attaining designed biofunctions.The self-assembly of rationally designed amphiphilic molecules,macromolecules and polymers represent another important approach for the construction of supramolecular architectures with advanced biofunctions.In this review,we summarize the important contributions made by Chinese researchers in this field,with emphasis on those reported in the past five years.

Structural and functional imaging of brains

Analyzing the complex structures and functions of brain is the key issue to understanding the physiological and pathological processes.Although neuronal morphology and local distribution of neurons/blood vessels in the brain have been known,the subcellular structures of cells remain challenging,especially in the live brain.In addition,the complicated brain functions involve numerous functional molecules,but the concentrations,distributions and interactions of these molecules in the brain are still poorly understood.In this review,frontier techniques available for multiscale structure imaging from organelles to the whole brain are first overviewed,including magnetic resonance imaging(MRI),computed tomography(CT),positron emission tomography(PET),serial-section electron microscopy(ss EM),light microscopy(LM)and synchrotron-based X-ray microscopy(XRM).Specially,XRM for three-dimensional(3D)imaging of large-scale brain tissue with high resolution and fast imaging speed is highlighted.Additionally,the development of elegant methods for acquisition of brain functions from electrical/chemical signals in the brain is outlined.In particular,the new electrophysiology technologies for neural recordings at the single-neuron level and in the brain are also summarized.We also focus on the construction of electrochemical probes based on dual-recognition strategy and surface/interface chemistry for determination of chemical species in the brain with high selectivity and long-term stability,as well as electrochemophysiological microarray for simultaneously recording of electrochemical and electrophysiological signals in the brain.Moreover,the recent development of brain MRI probes with high contrast-to-noise ratio(CNR)and sensitivity based on hyperpolarized techniques and multi-nuclear chemistry is introduced.Furthermore,multiple optical probes and instruments,especially the optophysiological Raman probes and fiber Raman photometry,for imaging and biosensing in live brain are emphasized.Finally,a brief perspective on existing challenges and further research development is provided.

Biomedical polymers: synthesis, properties, and applications

Biomedical polymers have been extensively developed for promising applications in a lot of biomedical fields, such as therapeutic medicine delivery, disease detection and diagnosis, biosensing, regenerative medicine, and disease treatment. In this review, we summarize the most recent advances in the synthesis and application of biomedical polymers, and discuss the comprehensive understanding of their property-function relationship for corresponding biomedical applications. In particular, a few burgeoning bioactive polymers, such as peptide/biomembrane/microorganism/cell-based biomedical polymers, are also introduced and highlighted as the emerging biomaterials for cancer precision therapy. Furthermore, the foreseeable challenges and outlook of the development of more efficient, healthier and safer biomedical polymers are discussed. We wish this systemic and comprehensive review on highlighting frontier progress of biomedical polymers could inspire and promote new breakthrough in fundamental research and clinical translation.