Detection of peptide-based nanoparticles in blood plasma by ELISA

Aims: The aim of the current study was to develop a method to detect peptide-linked nanoparticles in blood plasma. Materials & Methods: A convenient enzyme linked immunosorbent assay (ELISA) was developed for the detection of peptides functionalized with biotin and fluorescein groups. As a proof of principle, polymerized pentafluorophenyl methacrylate nanoparticles linked to biotin-carboxyfluorescein labeled peptides were intravenously injected in Wistar rats. Serial blood plasma samples were analyzed by ELISA and by liquid chromatography mass spectrometry (LC/MS) technology. Results: The ELISA based method for the detection of FITC labeled peptides had a detection limit of 1 ng/mL. We were able to accurately measure peptides bound to pentafluorophenyl meth-acrylate nanoparticles in blood plasma of rats, and similar results were obtained by LC/MS. Conclusions: We detected FITC-labeled peptides on pentafluorophenyl methacrylate nanoparticles after injection in vivo. This method can be extended to detect nanoparticles with different chemical compositions

Induction of the Columnar Phase of Unconventional Dendrimers by Breaking the C2 Symmetry of Molecules

[[abstract]]Two triazine-based unconventional dendrimers were prepared and characterized by 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. Differential scanning calorimetry, polarizing microscopy, and powder XRD studies showed that these dendrimers display columnar liquid-crystalline phases during thermal treatment. This is ascribable to breaking of their C2 symmetry. The molecular conformations of prepared dendrimers were obtained by computer simulation with the MM3 model of the CaChe program in the gas phase. The simulation showed that the conformations of the prepared dendrimers are rather flat and disfavor formation of the LC phase. However, due to C2-symmetry breaking, the prepared dendrimers have structural isomers in the solid state and thus show the desired columnar phases. This new strategy should be applicable to other types of unconventional dendrimers with rigid frameworks.[[journaltype]]國外[[incitationindex]]SCI[[ispeerreviewed]]Y[[booktype]]電子版[[booktype]]紙本[[countrycodes]]DE

Formation of Columnar Liquid Crystals on the Basis of Unconventional Triazine-Based Dendrimers by the C3-Symmetric Approach

[[abstract]]Two series of unconventional triazine-based dendrimers with C2 symmetry and C3 symmetry were prepared. The newly prepared C3-symmetrical dendrimers were characterized by 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. Differential scanning calorimetry, polarizing microscopy, and powder XRD showed that the C3-symmetrical dendrimers display columnar liquid-crystalline phases during thermal treatment, but the C2-symmetrical dendrimers were not observed to behave correspondingly. The molecular conformations of C3- and C2-symmetrical dendrimers were obtained by computer simulation with the MM2 model of the CaChe program in the gas phase. The simulation results reasonably explain the different mesogenicities of C3- and C2-symmetric dendrimers. This new strategy should be applicable to other types of unconventional dendrimers with rigid frameworks for displaying columnar liquid-crystalline behavior.[[journaltype]]國外[[incitationindex]]SCI[[ispeerreviewed]]Y[[booktype]]紙本[[countrycodes]]DE

Integrin alpha V beta 3 targeted dendrimer‐rapamycin conjugate reduces fibroblast‐mediated prostate tumor progression and metastasis

Therapeutic strategies targeting both cancer cells and associated cells in the tumor microenvironment offer significant promise in cancer therapy. We previously reported that generation 5 (G5) dendrimers conjugated with cyclic‐RGD peptides target cells expressing integrin alpha V beta 3. In this study, we report a novel dendrimer conjugate modified to deliver the mammalian target of rapamycin (mTOR) inhibitor, rapamycin. In vitro analyses demonstrated that this drug conjugate, G5‐FI‐RGD‐rapamycin, binds to prostate cancer (PCa) cells and fibroblasts to inhibit mTOR signaling and VEGF expression. In addition, G5‐FI‐RGD‐rapamycin inhibits mTOR signaling in cancer cells more efficiently under proinflammatory conditions compared to free rapamycin. In vivo studies established that G5‐FI‐RGD‐rapamycin significantly inhibits fibroblast‐mediated PCa progression and metastasis. Thus, our results suggest the potential of new rapamycin‐conjugated multifunctional nanoparticles for PCa therapy.Here, we synthesized and characterized a novel dendrimer conjugate, G5‐FI‐RGD‐rapamycin. Multifunctional G5‐FI‐RGD‐rapamycin binds to PCa and fibroblasts via alpha V beta 3 integrin and significantly inhibits mTOR signaling and VEGF expression. These in vitro data were confirmed by in vivo data that G5‐FI‐RGD‐rapamycin inhibits fibroblast‐mediated PCa progression and metastasis.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146470/1/jcb26727.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146470/2/jcb26727_am.pd

Facile Preparation of Organic Nanoparticles by Interfacial Cross-Linking of Reverse Micelles and Template Synthesis of Subnanometer Au−Pt Nanoparticles

A single- and a double-tailed cationic surfactant with the triallylammonium headgroup formed reverse micelles (RMs) in heptane/chloroform containing a small amount of water. The reverse micelles were cross-linked at the interface upon UV irradiation in the presence of a water-soluble dithiol cross-linker and a photoinitiator. The resulting interfacially cross-linked reverse micelles (ICRMs) of the single-tailed surfactant aggregated in a solvent-dependent fashion, whereas those of the double-tailed were identical in size as the corresponding RMs. The ICRMs could extract anionic metal salts, such as AuCl4− and PtCl62−, from water into the organic phase. Au and Pt metal nanoparticles were produced upon reduction of metal salts. The covalent nature of the ICRMs made the template synthesis highly predictable, with the size of the metal particles controlled by the amount of the metal salt and the method of reduction. Nanoalloys were obtained by combining two metal precursors in the same reaction. Reduction of the ICRM-entrapped aurate also occurred without any external reducing agents, and the gold nanoparticles differed dramatically from those obtained through sodium borohydride reduction. The same template allowed the preparation of luminescent Au4, Au8, and Au13−Au23 clusters, as well as gold nanoparticles several nanometers in size, simply by using different amounts of gold precursor and reducing conditions