There are currently some problems in the field of chemical synthesis, such as environmental impact, energy loss, and safety, that need to be tackled urgently. An interdisciplinary approach, based on different backgrounds, may succeed in solving these problems. Organisms can be chosen as potential platforms for materials fabrication, since biosystems are natural and highly efficient. Here, an example of how to solve some of these chemical problems through biology, namely, through a novel biological strategy of coupling intracellular irrelated biochemical reactions for controllable synthesis of multicolor CdSe quantum dots (QDs) using living yeast cells as a biosynthesizer, is demonstrated. The unique fluorescence properties of CdSe QDs can be utilized to directly and visually judge the biosynthesis phase to fully demonstrate this strategy. By such a method, CdSe QDs, emitting at a variety of single fluorescence wavelengths, can be intracellularly, controllably synthesized at just 30°C instead of at 300°C with combustible, explosive, and toxic organic reagents. This green biosynthetic route is a novel strategy of coupling, with biochemical reactions taking place irrelatedly, both in time and space. It involves a remarkable decrease in reaction temperature, from around 300 °C to 30 °C and excellent color controllability of CdSe photoluminescence. It is well known that to control the size of nanocrystals is a mojor challenge in the biosynthesis of high‐quality nanomaterials. The present work demonstrates clearly that biological systems can be creatively utilized to realize controllable unnatural biosynthesis that normally does not exist, offering new insights for sustainable chemistry.

As traditional anticancer treatments fail to significantly improve the prognoses, exploration of therapeutic modalities is urgently needed. Herein, a biomimetic magnetosome is constructed to favor the ferroptosis/immunomodulation synergism in cancer. This magnetosome is composed of an Fe3O4 magnetic nanocluster (NC) as the core and pre-engineered leukocyte membranes as the cloak, wherein TGF-β inhibitor (Ti) can be loaded inside the membrane and PD-1 antibody (Pa) can be anchored on the membrane surface. After intravenous injection, the membrane camouflage results in long circulation, and the NC core with magnetization and superparamagnetism enables magnetic targeting with magnetic resonance imaging (MRI) guidance. Once inside the tumor, Pa and Ti cooperate to create an immunogenic microenvironment, which increases the amount of H2O2 in polarized M1 macrophages and thus promotes the Fenton reaction with Fe ions released from NCs. The generated hydroxyl radicals (•OH) subsequently induce lethal ferroptosis to tumor cells, and the exposed tumor antigen, in turn, improves the microenvironment immunogenicity. The synergism of immunomodulation and ferroptosis in such a cyclical manner therefore leads to potent therapeutic effects with few abnormalities, which supports the engineered magnetosomes as a promising combination modality for anticancer therapy.

Exosomes hold great potential in therapeutic development. However, native exosomes usually induce insufficient effects in vivo and simply act as drug delivery vehicles. Herein, we synthesize responsive exosome nano‐bioconjugates for cancer therapy. Azide‐modified exosomes derived from M1 macrophages are conjugated with dibenzocyclooctyne‐modified antibodies of CD47 and SIRPα (aCD47 and aSIRPα) through pH‐sensitive linkers. After systemic administration, the nano‐bioconjugates can actively target tumors through the specific recognition between aCD47 and CD47 on the tumor cell surface. In the acidic tumor microenvironment, the benzoic‐imine bonds of the nano‐bioconjugates are cleaved to release aSIRPα and aCD47 that can, respectively, block SIRPα on macrophages and CD47, leading to abolished “don't eat me” signaling and improved phagocytosis of macrophages. Meanwhile, the native M1 exosomes effectively reprogram the macrophages from pro‐tumoral M2 to anti‐tumoral M1.

Uncovering the mechanisms of virus infection and assembly is crucial for preventing the spread of viruses and treating viral disease. The technique of single-virus tracking (SVT), also known as single-virus tracing, allows one to follow individual viruses at different parts of their life cycle and thereby provides dynamic insights into fundamental processes of viruses occurring in live cells. SVT is typically based on fluorescence imaging and reveals insights into previously unreported infection mechanisms. In this review article, we provide the readers a broad overview of the SVT technique. We first summarize recent advances in SVT, from the choice of fluorescent labels and labeling strategies to imaging implementation and analytical methodologies. We then describe representative applications in detail to elucidate how SVT serves as a valuable tool in virological research. Finally, we present our perspectives regarding the future possibilities and challenges of SVT. CONTENTS a Maximum excitation wavelength. b Maximum emission wavelength. c Extinction coefficient. d Fluorescence quantum yield. e The relative brightness values were calculated from the product of the molar extinction coefficient and quantum yield, divided by the value for EGFP. f Not determined.

Luminescent labeling and magnetic separation are two important bio-techniques. Materials with the combined function of these two properties have many applications in biomedical science. The common strategy of producing such materials is to anchor magnetic nanoparticles and organic fluorophores to two types of molecules that can interact with each other. [1] Recently, several methods have been developed by using QDs and magnetic nanoparticles, [2] and encapsulating both particles in polymer microcapsules. [3] However, the development of bifunctional nanoparticles with higher structural stability and more specific binding is instantly desired. In this work, we propose a new strategy to fabricate bifunctional nanospheres (BFNs) with both fluorescence and magnetism, [4] and further to construct trifunctional nanospheres (TFNs), which show capacity of capture and separation of specific cancer cells.The BFNs were prepared by embedding fluorescent CdSe/ZnS QDs and magnetic nano-g-Fe 2 O 3 into hydrazinized styrene/acrylamide (H 2 N-St-AAm) copolymer nanospheres simultaneously. In order to ensure that both the QDs and magnetic nanoparticles are embedded, the particles must be small and well dispersed in an identical solvent. Therefore hydrophobic QDs and ferromagnetic nanoparticles were prepared. A new method for the preparation of nano-Fe 2 O 3 through a high-temperature decomposition route was then developed based on a reported method. [5] Xray diffraction (XRD) indicated that the crystal structure of the product was cubic g-Fe 2 O 3 (Figure 1 a) rather than Fe 3 O 4 . [5] It is because our experiments were carried out in air and in the absence of 1,2-hexadecanediol, which may reduce iron cations. Transmission electron microscopy (TEM) results indicate that the particles have an average particle size smaller than 20 nm with a narrow size distribution and are well dispersed (Figure 1 b).St-AAm copolymer nanospheres were synthesized from styrene and acrylamide by a modified method of emulsifierfree polymerization. [6] The size of the spheres can be changed from 50 to 500 nm by adjusting the concentration of raw materials and the dosage of the trigger. Scanning electron microscopy (SEM) images imply that the surface of the spheres is mesoporous, thus providing an entry route for nanoparticles ( Figure 2). As the scheme is emulsifier-free, the surface is relatively clean and convenient for conjugating with other molecules.The hydrophilic groups of the polymer tend to be located towards the outer surface of the nanospheres, while the hydrophobic moieties are found at the interior, leading to the formation of hydrophobic hollow cavities, since the nanospheres are synthesized in an aqueous solution. Both hydrophobic QDs (3-6 nm) and nano-g-Fe 2 O 3 (5-20 nm) were embedded in a weakly polar organic solvent. As shown in Figure 2, the particles are widely distributed inside the nanospheres with a relatively clean surface. It is notice-Figure 1. a) XRD pattern indexed onto a face-centred-cubic unit cell with a = 0.835 nm; b) TEM...