Direct Detection of Circulating Tumor Cells in Whole Blood Using Time‐Resolved Luminescent Lanthanide Nanoprobes

The detection of circulating tumor cells (CTCs) is crucial to early cancer diagnosis and the evaluation of cancer metastasis. However, it remains challenging due to the scarcity of CTCs in the blood. Herein, we report an ultrasensitive platform for the direct detection of CTCs using luminescent lanthanide nanoprobes. These were designed to recognize the epithelial cell adhesion molecules on cancer cells, allowing signal amplification through dissolution‐enhanced time‐resolved photoluminescence (TRPL) and the elimination of short‐lived autofluorescence interference. This enabled the direct detection of blood breast‐cancer cells with a limit of detection down to 1 cell/well of a 96‐well plate. Moreover, blood CTCs (≥10 cells mL^?1) can be detected in cancer patients with a detection rate of 93.9 % (14/15 patients). We envision that this ultrasensitive detection platform with excellent practicality may provide an effective strategy for early cancer diagnosis and prognosis evaluation.     

Time‐Resolved Interception of Multiple‐Charge Accumulation in a Sensitizer–Acceptor Dyad

Biomimetic models that contain elements of photosynthesis are fundamental in the development of synthetic systems that can use sunlight to produce fuel. The critical task consists of running several rounds of light‐induced charge separation, which is required to accumulate enough redox equivalents at the catalytic sites for the target chemistry to occur. Long‐lived first charge‐separated state and distinct electronic signatures for the sequential charge accumulated species are essential features to be able to track these events on a spectroscopic ground. Herein, we use a double‐excitation nanosecond pump–pump–probe experiment to interrogate two successive rounds of photo‐induced electron transfer on a molecular dyad containing a naphthalene diimide (NDI) linked to a [Ru(bpy)₃]²⁺ (bpy=bipyridine) chromophore by using a reversible electron donor. We report an unprecedented long‐lived two‐electron charge accumulation (t =200 μs).     

Quantifying Hydrogen‐Bond Populations in Dimethyl Sulfoxide/Water Mixtures

Dimethyl sulfoxide (DMSO) disrupts the hydrogen‐bond networks in water. The widespread use of DMSO as a cosolvent, along with its unusual attributes, have inspired numerous studies. Herein, infrared absorption spectroscopy of the S=O stretching mode combined with molecular dynamics and quantum chemistry models were used to directly quantify DMSO/water hydrogen‐bond populations in binary mixtures. Singly H‐bonded species are dominant at 10 mol %, due to strong DMSO–water interactions. We found an unexpected increase in non‐hydrogen‐bonded DMSO near the eutectic point (ca. 35 mol %) which also correlates with several abnormalities in the bulk solution properties. We find evidence for three distinct regimes: 1) strong DMSO–water interactions (<30 mol %), 2) ideal‐solution‐like (30–90 mol %), and 3) self‐interaction, or aggregation, regime (>90 mol %). We propose a “step in” mechanism, which involves hydrogen bonding between water and the DMSO aggregate species.     

Interpenetration Isomerism in Triptycene‐Based Hydrogen‐Bonded Organic Frameworks

We describe an example of “interpenetration isomerism” in three‐dimensional hydrogen‐bonded organic frameworks. By exploiting the crystallization conditions for a peripherally extended triptycene H₆PET, we can modulate the interpenetration of the assembled frameworks, yielding a two‐fold interpenetrated structure PETHOF‐ 1 and a five‐fold interpenetrated structure PETHOF‐ 2 as interpenetration isomers. In PETHOF‐ 1 , two individual nets are related by inversion symmetry and form an interwoven topology with a large guest‐accessible volume of about 80 %. In PETHOF‐ 2 , five individual nets are related by translational symmetry and are stacked in an alternating fashion. The activated materials show permanent porosity with Brunauer‐Emmett‐Teller surface areas exceeding 1100 m² g^?1. Synthetic control over the framework interpenetration could serve as a new strategy to construct complex supramolecular architectures from simple organic building blocks.