Effect of the chemical nature and length of spacer arms on the covalent grafting of fluorinated molecular probes at the surface of poly(ethylene terephthalate) membrane

Abstract

A series of fluorinated molecular probes were synthesized that are characterized by spacer arms of various lengths and polarities. Previous molecules (1, 2a, 2b, 2c, 3a, 3b) were covalently fixed on the surface of poly(ethylene terephthalate) (PET) membranes via activated hydroxyl chain endings. X‐ray photoelectron microscopic analysis of the grafted samples allowed us to quantify the PET surface reactivity; the results were within 40–50 pmol/cm2 of fixed probes, independent of the length and hydrophilicity of the spacer arms. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 770–781, 2002; DOI 10.1002/pola.10156

Design, synthesis and evaluation of graftable thrombin inhibitors for the preparation of blood-compatible polymer materials

“…This strategy was already successfully used in our laboratory for polymer functionalization. 22 Chainend hydroxyl groups of PET and PBT membranes were activated with p-toluenesulfonyl chloride (TsCl) and pyridine. The incubation of activated membranes with inhibitor solutions should provide sulfonyl ester displacement and covalent fixation of the active molecules on the surfaces (Scheme 3).…”

“…We considered a simplified structure of Argatroban 1 (Fig. 1) featuring the following characteristics: (i) the guanidyl function of the L-arginine skeleton, for specific ionic interaction with Asp-189 in the S1 enzyme pocket-since oral bioavailability 14 is not a relevant problem in the field of hemocompatible materials, this strongly basic function could be maintained as a recognizing function; (ii) the lipophilic sulfonamide moiety, for interaction with the S2-S3 binding sites-this substituent was also used to introduce a trifluoromethyl group as a useful spectroscopic tag 22 for XPS (X-ray photoelectron spectroscopy) analysis of the biomaterial surface and quantification of the amount of grafted inhibitor; (iii) the piperidinyl amide moiety (X = CH 2 ), stable towards processing by the active serine of thrombin and blood esterases-it has been proven that the acid function placed on the piperidine ring of Argatroban is not absolutely necessary for activity.…”

αvβ3 Integrin-Targeting Arg-Gly-Asp (RGD) Peptidomimetics Containing Oligoethylene Glycol (OEG) Spacers

“…The basic motifs were connected by using either a propyl (n = 1) or a butyl chain (n = 2), in view of adjusting the distance between the acidic and basic moieties to about 12-14 Å . 42 The length of the spacer was of three (p = 2) or six (p = 5) ethyleneglycol units, according to a previous study, 43 and the terminal function for grafting on materials was a primary amine. The precursor 1 was already described 34 (45% yield in two steps from commercial t-butyl tyrosinate; 1 g scale), but as we needed large quantities, a practical synthesis was developed starting from (L)-tyrosine (see Supporting Information).…”

“…The native membrane was activated by a wet chemistry treatment with trifluorotriazine 76 and then incubated with the adhesive molecules to furnish the supports named PET-g-8b, PET-g-9a, PET-g-9b, and PET-g-RGD, respectively. The rates of surface functionalization were determined by X-ray photoelectron spectroscopy (XPS) 43 and the recorded percentages of grafting converted into pmol/cm 2 of apparent surface for comparing the samples. b Structure from X-ray data of the complex with the receptor.…”

Surface functionalization of germanium ATR devices for use in FTIR-biosensors

“…The resulting device (Si-PEG-NHS) features activated ester functions, ready for trapping amine-terminated molecules. This surface reactivity was assayed by coupling 3,5-bis(trifluoromethyl)benzylamine (6) considered as a fluorinated tag for the XPS analysis [40]. After covalent grafting of 6 (Scheme 2, step iii), the device surface (Si-PEG-F6) was characterized by XPS, comparatively to the native device (Si-OH), and the intermediately functionalized device (Table 2).…”