1.Pentafluorophenyl Ester-based Polymersomes as Nanosized Drug-Delivery Vehicles.
Scherer M1, Fischer K2, Depoix F3, Fritz T4, Thiermann R5, Mohr K6, Zentel R1. Macromol Rapid Commun. 2015 Oct 19. doi: 10.1002/marc.201500444. [Epub ahead of print]
In this work, activated ester chemistry is employed to synthesize biocompatible and readily functionalizable polymersomes. Via aminolysis of pentafluorophenyl methacrylate-based precursor polymers, an N-(2-hydroxypropyl) methacrylamide (HPMA)-analog hydrophilic block is obtained. The precursor polymers can be versatile functionalized by simple addition of suitable primary amines during aminolysis as demonstrated using a fluorescent dye. Vesicle formation is proven by cryoTEM and light scattering. High encapsulation efficiencies for hydrophilic cargo like siRNA are achieved using dual centrifugation and safe encapsulation is demonstrated by gel electrophoresis. In vitro studies reveal low cytotoxicity and no protein adsorption-induced aggregation in human blood serum occurs, making the vesicles interesting candidates as nanosized drug carriers.
2.Acoustic wave biosensor for the detection of the breast and prostate cancer metastasis biomarker protein PTHrP.
Crivianu-Gaita V1, Aamer M1, Posaratnanathan RT1, Romaschin A2, Thompson M3. Biosens Bioelectron. 2016 Apr 15;78:92-9. doi: 10.1016/j.bios.2015.11.031. Epub 2015 Nov 12.
There are currently no biosensors that are able to reliably detect the process of cancer metastasis. We describe the first label-free real-time ultra-high frequency acoustic wave biosensor prototype capable of detecting the breast and prostate cancer metastasis biomarker, parathyroid hormone-related peptide (PTHrP). Two different linkers - 11-trichlorosilyl-undecanoic acid pentafluorophenyl ester (PFP) and S-(11-trichlorosilyl-undecanyl)-benzothiosulfonate (TUBTS) - were used to immobilize whole anti-PTHrP antibodies and Fab' fragments to surfaces as biorecognition elements. The biosensor surfaces were optimized using X-ray photoelectron spectroscopy (XPS) and the ultra-high frequency electromagnetic piezoelectric acoustic sensor (EMPAS). One optimized whole antibody-based surface (PFP/protein G'/whole antibodies/ethanolamine) and one optimized Fab' fragment-based surface (TUBTS/Fab' fragments) were tested as biosensors. It was determined that an in-line injection of bovine serum albumin prior to analyte injection yielded the most minimally fouling surfaces.
3.Synthesis and Biological Evaluation of a Valinomycin Analog Bearing a Pentafluorophenyl Active Ester Moiety.
D'Accolti L1, Denora N, La Piana G, Marzulli D2, Siwy ZS3, Fusco C1, Annese C1. J Org Chem. 2015 Dec 18;80(24):12646-50. doi: 10.1021/acs.joc.5b02219. Epub 2015 Nov 23.
A valuable analog of the K(+)-ionophore valinomycin (1), bearing a pentafluorophenyl ester moiety, has been obtained by selective reaction between the tertiary hydroxyl moiety of analog 2 (available from valinomycin hydroxylation) and the isocyanate group of pentafluorophenyl N-carbonyl glycinate (3) catalyzed by bis(N,N-dimethylformamide)dichlorodioxomolybdenum(VI). LC-HRMS studies show that analog 4 undergoes easy derivatization under mild conditions by reaction with OH- and NH2-containing compounds. Mitochondrial depolarization assays suggest that 4 acts as a K(+)-ionophore, provided that the glycine carboxyl group is appropriately masked.
4.Imparting Nonfouling Properties to Chemically Distinct Surfaces with a Single Adsorbing Polymer: A Multimodal Binding Approach.
Serrano Â1,2, Zürcher S1,2, Tosatti S1,2, Spencer ND2. Macromol Rapid Commun. 2016 Apr;37(7):622-9. doi: 10.1002/marc.201500683. Epub 2016 Feb 9.
Surface-active polymers that display nonfouling properties and carry binding groups that can adsorb onto different substrates are highly desirable. We present a postmodification protocol of an active-ester-containing polymer that allows the creation of such a versatile platform. Poly(pentafluorophenyl acrylate) has been postmodified with a fixed grafting ratio of a nonfouling function (mPEG) and various combinations of functional groups, such as amine, silane and catechol, which can provide strong affinity to two model substrates: SiO2 and TiO2 . Adsorption, stability and resistance to nonspecific protein adsorption of the polymer films were studied. A polymer was obtained that maintained its surface functionality under a variety of harsh conditions. EG surface-density calculations show that this strategy generates a denser packing when both negatively and positively charged groups are present within the backbone, and readily allows the fabrication of a broad combinatorial matrix.