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The development of nanotheranostic agents that integrate diagnosis and therapy for effective personalized precision medicine has obtained tremendous attention in the past few decades. In this report, biocompatible electron donor–acceptor conjugated semiconducting polymer nanoparticles (PPor-PEG NPs) with light-harvesting unit is prepared and developed for highly effective photoacoustic imaging guided photothermal therapy. To the best of our knowledge, it is the first time that the concept of light-harvesting unit is exploited for enhancing the photoacoustic signal and photothermal energy conversion in polymer-based theranostic agent. Combined with additional merits including donor–acceptor pair to favor electron transfer and fluorescence quenching effect after NP formation, the photothermal conversion efficiency of the PPor-PEG NPs is determined to be 62.3%, which is the highest value among reported polymer NPs. Moreover, the as-prepared PPor-PEG NP not only exhibits a remarkable cell-killing ability but also achieves 100% tumor elimination, demonstrating its excellent photothermal therapeutic efficacy. Finally, the as-prepared water-dispersible PPor-PEG NPs show good biocompatibility and biosafety, making them a promising candidate for future clinical applications in cancer theranostics.

Large‐area graphene nanomesh (GNM) is prepared using a new and effective method, in which the O2 plasma treatment is used with an anodic aluminum oxide (AAO) membrane as an etch mask. By varying the pore size and cell wall thickness of the AAO membrane, GNM with tunable pore size and neck width can be prepared. As proof of concept, a field‐effect transistor with 15 nm neck width GNM as the conductive channel is fabricated, which exhibits p‐type semiconducting behavior.

Dear Editor, The COVID-19 pandemic worldwide is caused by a novel coronavirus SARS-CoV-2 (the severe acute respiratory syndrome coronavirus 2). 1 After viral invasion into the host cells, the~30 kb viral genome RNA injected is translated into structural and nonstructural proteins to replicate viral genome and assemble more viral particles. Many copies of nucleocapsid (N) protein can bind to viral genome RNA and pack it into~100 nm particles, assisting membrane (M) and envelope (E) proteins to efficiently assemble the viral envelope. 2 The exact molecular mechanism by which N protein packs up the viral genome still remains elusive. An N protein of SARS-CoV-2 consists of an N-terminal RNAbinding domain (NTD) and a C-terminal dimerization domain (CTD) and shares~90% sequence identity with N protein of SARS-CoV (Supplementary information, Fig. S1a). The regions located between the N-terminus and NTD, between NTD and CTD, and between CTD and the C-terminus of the N protein of SARS-CoV-2 (thereafter referred to as N protein) are predicted to be intrinsically disordered (Supplementary information, Fig. S1b, c). At neutral pH, the N protein is positively charged (+24 e), consistent with its strong binding affinity with negatively charged

By constructing a conjoined-network, we tackled the challenge in developing stiff and tough hydrogels of biogenic molecules.

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Gold (Au) nanoparticles that display strong two-photon photoluminescence (TPPL) are attractive contrast agents for noninvasive live cell/tissue imaging with deep penetration because of their excellent biocompatibility and low cytotoxicity. The TPPL properties of Au nanoparticles are strongly dependent on the particle shape. As chemically prepared nanoparticles are generally inhomogeneous, conventional ensemble-based TPPL measurements can only give averaged results of particles of different morphologies. Singleparticle spectroscopy can avoid the complication induced by the sample inhomogeneity in ensemble measurements and help to establish the morphology−property relationship. Here we have investigated the scattering spectra and TPPL properties of Au nanoparticles of different shapes on the single particle level and explored their potential applications in cancer cell imaging. Au nanoparticles of five different shapes (nanospheres, nanocubes, nanotriangles, nanorods, and nanobranches) with similar dimensions have been chosen for the study. The TPPL spectra of these Au nanoparticles were found to be strongly modulated by plasmon resonance. TPPL intensity increases in the order of nanospheres, nanocubes, nanotriangles, nanorods, and nanobranches. The averaged TPPL intensity of a single Au nanobranch is 47750 times that of a single Au nanosphere. Two-photon action cross sections of single Au NSs, Au NCs, Au NTs, Au NRs, and Au NBs were estimated to be ∼83, ∼500, ∼1.5 × 10 3 , ∼4.2 × 10 4 , and ∼4.0 × 10 6 GM, respectively. Laser-induced melting experiments on single Au nanobranches demonstrate that the tips played an important role in the observed strong TPPL. Application of these Au nanobranches as excellent two-photon imaging contrast agents has been demonstrated on HepG2 cancer cells.