Repurposing organic semiconducting nanomaterials to accelerate clinical translation of NIR-II fluorescence imaging

Optical imaging possesses important implications for early disease diagnosis,timely disease treatment,and basic medical as well as biological research.Compared with the traditionary near-infrared(NIR-I)window(650-950 nm)optical imaging,the emerging second near-infrared(NIR-II)window optical imaging technology owns the great superiorities of non-invasiveness,nonionizing radiation,and real-time dynamic imaging with the low biological interference,can significantly improve the tissue penetration depth and detection sensitivity,thus expecting to achieve accurate and precise diagnosis of major diseases.Inspired by the conspicuous superiorities,an increasing number of versatile NIR-II fluorophores have been legitimately designed and engineered for precisely deep-tissue mapping-mediated theranostics of life-threatening diseases.Organic semiconducting nanomaterials(OSNs)are derived from organic conjugated molecules withπ-electron delocalized skeletons,which show greatly preponderant prospects in the biomedicine field due to the excellent photoelectric property,tunable energy bands,and fine biocompatibility.In this review,the superiorities of NIR-II fluorescence imaging using OSNs for brilliant visualization various of diseases,including tongue cancer,ovarian cancer,osteosarcoma,bacteria or pathogens infection,kidney dysfunction,rheumatoid arthritis,liver injury,and cerebrovascular function,are emphatically summarized.Finally,the reasonable prospects and persistent efforts for repurposing OSNs to facilitate the clinical translation of NIR-II fluorescence phototheranostics are outlined.

Response of organic aerosol characteristics to emission reduction in Yangtze River Delta region

Organic aerosol(OA)is a major component of atmospheric particulate matter(PM)with complex composition and formation processes influenced by various factors.Emission reduction can alter both precursors and oxidants which further affects secondary OA formation.Here we provide an observational analysis of secondary OA(SOA)variation properties in Yangtze River Delta(YRD)of eastern China in response to large scale of emission reduction during Chinese New Year(CNY)holidays from 2015 to 2020,and the COVID-19 pandemic period from January to March,2020.We found a 17%increase of SOA proportion during the COVID lockdown.The relative enrichment of SOA is also found during multi-year CNY holidays with dramatic reduction of anthropogenic emissions.Two types of oxygenated OA(OOA)influenced by mixed emissions and SOA formation were found to be the dominant components during the lockdown in YRD region.Our results highlight that these emission-reduction-induced changes in organic aerosol need to be considered in the future to optimize air pollution control measures.