Search

Active targeted nanotechnology‐based drug delivery systems have gained significant favor because they have the ability to decrease side effects, improve drug bioavailability, and the potency of anticancer treatment. In this study, functional amphiphilic Janus nanoparticles (JNPs), consisting of hydrophilic and hydrophobic biocompatible polymers as two distinct sides, have been prepared via a robust and simple synthesis method. The surface‐active hydrophilic side of this Janus platform is functionalized with an aptamer against epithelial cell adhesion molecule (EpCAM) to deliver Doxorubicin (DOX) for the treatment of metastasis colorectal adenocarcinoma HT29 cells. The Janus morphology of the nanoparticles and their cell penetration behavior are shown in microscopic evaluations. By evaluating the prepared DOX‐loaded aptamer–modified JNPs by cell‐toxicity assay and confocal microscopy, it was determined that the utilization of an internalization strategy to enhance cell uptake would increase the anticancer effect of the Janus nanocarrier and improve the capacity to deliver the chemotherapeutical drug site‐specifically. [ABSTRACT FROM AUTHOR]

Combination chemotherapy must strike a difficult balance between safety and efficacy. Current regimens suffer from poor therapeutic impact because drugs are given at their maximum tolerated dose (MTD), which compounds the toxicity risk and exposes tumors to non‐optimal drug ratios. A modular framework has been developed that selectively delivers drug combinations at synergistic ratios via tumor‐targeting aptamers for effective low‐dose treatment. A nucleolin‐recognizing aptamer was coupled to peptide scaffolds laden with precise ratios of doxorubicin (DOX) and camptothecin (CPT). This construct had an extremely low IC50 (31.9 nm) against MDA‐MB‐231 breast cancer cells in vitro, and exhibited in vivo efficacy at micro‐dose injections (500 and 350 μg kg−1 dose−1 of DOX and CPT, respectively) that are 20–30‐fold lower than their previously‐reported MTDs. This approach represents a generalizable strategy for the safe and consistent delivery of combination drugs in oncology. Targeted drug‐delivery: Combination chemotherapy regimens can be effective, but are often highly toxic and fail in clinics since drugs are given at their maximum tolerated doses. To achieve potent antitumor effects at extremely low doses, an aptamer–drug combination vehicle is described, designed to selectively deliver multiple therapeutic agents at a pre‐defined ratio for maximum effectiveness. [ABSTRACT FROM AUTHOR]

Magnetic nanomaterials find increasing application as separation agents to rapidly isolate target compounds from complex biological media (i.e., blood purification). The responsiveness of the used materials to external magnetic fields (i.e., their saturation magnetization) is one of the most critical parameters for a fast and thorough separation. In the present study, magnetite (Fe3O4) and non-oxidic cementite (Fe3C) based carbon-coated nanomagnets are characterized in detail and compared regarding their separation behavior from human whole blood. A quantification approach for iron-based nanomaterials in biological samples with strong matrix effects (here, salts in blood) based on platinum spiking is shown. Both materials are functionalized with polyethyleneglycol (PEG) to improve cytocompatibility (confirmed by cell toxicity tests) and dispersability. The separation performance is tested in two setups, namely under stationary and different flow-conditions using fresh human blood. The results reveal a superior separation behavior of the cementite based nanomagnets and strongly suggest the use of nanomaterials with high saturation magnetizations for magnetic retention under common blood flow conditions such as in veins. [ABSTRACT FROM AUTHOR]

High magnetic responsiveness is critical for nanomagnets in biomedicine, and fast and complete separation is essential for blood purification or targeted drug delivery, to diminish potential risks. However, studies on the collection efficiency of iron‐based nanoparticles are rare. On page 4888, W. J. Stark and co‐workers present a new quantification approach based on platinum doping of magnetite and carbon‐coated cementite nanoparticles. Their findings show that a good separation efficiency from human whole blood calls for nanomaterials with high saturation magnetizations. [ABSTRACT FROM AUTHOR]