Plasmodione ( PD ) is a potent antimalarial redox-active drug acting at low nM range concentrations on different malaria parasite stages. In this study, in order to determine the precise PD protein interactome in parasites, we developed a class of (pro-)activity-based protein profiling probes (ABPP) as precursors of photoreactive benzophenone-like probes based on the skeleton of PD metabolites ( PDO ) generated in a cascade of redox reactions. Under UV-photoirradiation, we clearly demonstrate that benzylic oxidation of 3-benzylmenadione 11 produces the 3-benzoylmenadione probe 7 , allowing investigation of the proof-of-concept of the ABPP strategy with 3-benzoylmenadiones 7 – 10 . The synthesized 3-benzoylmenadiones, probe 7 with an alkyne group or probe 9 with -NO 2 in para position of the benzoyl chain, were found to be the most efficient photoreactive and clickable probes. In the presence of various H-donor partners, the UV-irradiation of the photoreactive ABPP probes generates different adducts, the expected “benzophenone-like” adducts (pathway 1) in addition to “benzoxanthone” adducts (via two other pathways, 2 and 3). Using both human and Plasmodium falciparum glutathione reductases, three protein ligand binding sites were identified following photolabeling with probes 7 or 9 . The photoreduction of 3-benzoylmenadiones ( PDO and probe 9 ) promoting the formation of both the corresponding benzoxanthone and the derived enone could be replaced by the glutathione reductase-catalyzed reduction step. In particular, the electrophilic character of the benzoxanthone was evidenced by its ability to alkylate heme, as a relevant event supporting the antimalarial mode of action of PD . This work provides a proof-of-principle that (pro-)ABPP probes can generate benzophenone-like metabolites enabling optimized activity-based protein profiling conditions that will be instrumental to analyze the interactome of early lead antiplasmodial 3-benzylmenadiones displaying an original and innovative mode of action.

Magnetic nanogels (MNGs) are designed to have all the required features for their use as highly efficient trapping materials in the challenging task of selectively capturing circulating tumor cells (CTCs) from the bloodstream. Advantageously, the discrimination of CTCs from hematological cells, which is a key factor in the capturing process, can be optimized by finely tuning the polymers used to link the targeting moiety to the MNG. We describe herein the relationship between the capturing efficiency of CTCs with overexpressed transferrin receptors and the different strategies on the polymer used as linker to decorate these MNGs with transferrin (Tf). Heterobifunctional polyethylene glycol (PEG) linkers with different molecular weights were coupled to Tf in different ratios. Optimal values over 80% CTC capture efficiency were obtained when 3 PEG linkers with a length of 8 ethylene glycol (EG) units were used, which reveals the important role of the linker in the design of a CTC-sorting system.

Circulating tumor cells (CTCs) from peripheral blood account genetic information for cancer diagnosis and overall disease monitoring. Analysis of “liquid biopsy” holds immense promise as it may lead to new approaches for cancer treatment. The study reports effective and continuous flow microchannel system for isolating CTCs using transferrin conjugated 3D matrix synthesized by crosslinking polyethylene glycol‐Fe3O4 nanostructures for rapid and efficient capturing of CTCs. The platform provides option of using multiple microchannel units in series that can influence higher cell‐capture efficiency due to increasing cell‐substrate contact frequency. CTCs are captured with high efficiency even at low concentration of target cells (~90% at 25 cells per mL blood). Furthermore, the study demonstrates that the cell‐capture performance is influenced by topographic interactions between nanostructure based matrix and cancer cells of interest. In addition, this study demonstrates the “proof of concept” using 3D microchannel system having capacity of simultaneously capturing and permanently eliminating CTCs from peripheral blood samples. Further, the study evaluates clinical samples of colon and breast cancer patients for rapid isolation of CTCs. Conclusively, the present platform demonstrates inordinate capacity for cancer cell sorting, biological studies of CTCs, and cancer metastasis, potentially benefiting the real time liquid biopsy and early prognosis of cancer.

area was performed using orange II dye method. This amine group quantitation method was used to confirm silanization. Consequently, silane-functionalized glass slips were then subjected to Tf conjugation at marked sites where patterns were developed. Tf was chemically immobilized with aminefunctionalized silanated glass using N-(3-dimethylaminopropyl)-N-ethylcarbodiimide HCl (EDC · HCl) coupling reaction. The silanization provides the necessary amine groups to be

Detection of circulating tumor cells (CTCs) in the blood circulation holds immense promise as it predicts the overall probability of patient survival. Therefore, CTC-based technologies are gaining prominence as a "liquid biopsy" for cancer diagnostics and prognostics. Here, we describe the design and synthesis of two distinct multicomponent magnetic nanosystems for rapid capture and detection of CTCs. The multifunctional Magneto-Dendrimeric Nano System (MDNS) composed of an anchoring dendrimer that is conjugated to multiple agents such as near infrared (NIR) fluorescent cyanine 5 NHS (Cy5), glutathione (GSH), transferrin (Tf), and iron oxide (FeO) magnetic nanoparticle (MNP) for simultaneous tumor cell-specific affinity, multimodal high resolution confocal imaging, and cell isolation. The second nanosystem is a self-propelled microrocket that is composed of carbon nanotube (CNT), chemically conjugated with targeting ligand such as transferrin on the outer surface and FeO nanoparticles in the inner surface. The multicomponent nanosystems described here are highly efficient in targeting and isolating cancer cells thus benefiting early diagnosis and therapy of cancer.

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