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Porous silicon (pSi) is a prosperous biomaterial, biocompatible, and biodegradable. Obtaining regularly functionalized pSi surfaces is required in many biotechnology applications. Silane-PEG-NHS (triethoxysilane-polyethylene-glycol-N-hydroxysuccinimide) is useful for single-molecule studies due to its ability to attach to only one biomolecule. We investigate the functionalization of pSi with silane-PEG-NHS and compare it with two common grafting agents: APTMS (3-aminopropylotrimethoxysilane) as electrostatic linker, and APTMS modified with glutaraldehyde as covalent spacer. We show the arrangement of two proteins (collagen and bovine serum albumin) as a function of the functionalization and of the pore size. FTIR is used to demonstrate correct functionalization while fluorescence confocal microscopy reveals that silane-PEG-NHS results in a more uniform protein distribution. Reflection interference spectroscopy (RIfS) is used to estimate the attachment of linker and proteins. The results open a way to obtain homogenous chemical modified silicon supports with a great value in biosensing, drug delivery and cell biology. © 2015 Elsevier Inc.

10.1016/j.colsurfb.2014.07.027 Nanoporous anodic alumina (NAA) is a material with great interest in nanotechnology and with promising applications to biotechnology. Obtaining specific and regularly functionalized NAA surfaces is essential to obtain meaningful results and applications. Silane-PEG-NHS (triethoxysilane-polyethylene-glycol-N-hydroxysuccinimide) is a covalent linker commonly used for single-molecule studies. We investigate the functionalization of NAA with silane-PEG-NHS and compared with two common, but not single-molecule, grafting agents, APTMS (3-aminopropylotrimethoxysilane) as an electrostatic linker, and APTMS-GTA (3-aminopropylotrimethoxysilane-glutaraldehyde) as covalent. Another outcome of this study is to show how two proteins (collagen and bovine serum albumin, BSA) with different properties differentially arrange for different functionalizations and NAA pore sizes. FTIR is used to demonstrate the surface modification steps and fluorescence confocal microscopy reveals that silane-PEG-NHS results in a more homogeneous protein distribution in comparison to the other linkers. Reflection interference Fourier transform spectroscopy confirms the confocal fluorescence microscopy results and permits to estimate the amounts of linker and linked proteins within the pores. These results permit to obtain uniformly chemical modified NAA supports with a great value in biosensing, drug delivery and cell biology.

Twelve research groups participated in the ISOBM TD-3 Workshop in which the reactivity and specificity of 83 antibodies against prostate-specific antigen (PSA) were investigated. Using a variety of techniques including cross-inhibition assays, Western blotting, BIAcore, immunoradiometric assays and immunohistochemistry, the antibodies were categorized into six major groups which formed the basis for mapping onto two- and three-dimensional (2-D and 3-D) models of PSA. The overall findings of the TD-3 Workshop are summarized in this report. In agreement with all participating groups, three main antigenic domains were identified: free PSA-specific epitopes located in or close to amino acids 86-91; discontinuous epitopes specific for PSA without human kallikrein (hK2) cross-reactivity located at or close to amino acids 158-163; and continuous or linear epitopes shared between PSA and hK2 located close to amino acids 3-11. In addition, several minor and partly overlapping domains were also identified. Clearly, the characterization of antibodies from this workshop and the location of their epitopes on the 3-D model of PSA illustrate the importance of selecting appropriate antibody pairs for use in immunoassays. It is hoped that these findings and the epitope nomenclature described in this TD-3 Workshop are used as a standard for future evaluation of anti-PSA antibodies.

We reported previously that supplemental vitamin E enhances disease resistance and antibody titers and depresses bursal prostaglandin (PG) E2 in chicks. In order to determine if dietary fat composition alters PG response and interacted with vitamin E, tallow or vegetable oil high in n-6 polyunsaturated fatty acids were added to a cornsoybean meal chick diet. Comparisons were made among control cockerels and those fed diets containing safflower or corn oils or beef tallow at 3, 6 or 9% with each of these diets supplemented with 0 or 300 mg of all-rac-a-tocopheryl acetate (dla-tocophery1 acetate). In the first experiment chick antibody titers to sheep red blood cells were markedly stimulated by 6% tallow without added vitamin E. Unexpectedly, supplemental vitamin E depressed antibody titers only in the 6% tallow group. Dietary fat and supplemental vitamin E altered bursal but not splenic PGE2 values independent of inoculation. Overall, the combination of tallow and vitamin E supplementation vitamin E suppre...

Osteocalcin, a non-collagen bone-matrix protein, has been examined as a possible source of autochthonous14C data in fossil bones where collagen has been seriously degraded. Extraction procedures for osteocalcin yield a well-characterized product that can be clearly distinguished from collagen. The Gla content indicates that osteocalcin is present in the fossil bones at levels similar to the range present in modern bone. However, it appears to be extracted primarily as proteolytic polypeptide fragments rather than as an intact protein. Concordant14C determinations are obtained on osteocalcin and gelatin extracts from the same bone when the collagen is relatively well preserved. However, increasing discordances in the14C values of the osteocalcin and gelatin fractions are associated with reduced concentrations of the gelatin extract in the bone.

Graphite in various forms has become the standard target for accelerator 14C dating. Graphite has been made by catalytic graphitization of charcoals (Lowe, 1984). Thin films of graphite have also been produced by thermal cracking (Beukens & Lee, 1981), electric discharge (Andrée et al, 1984; Wand, Gillespie & Hedges, 1984). Vogel et al (1984) pointed out the ease of graphite formation on iron from CO2 and H2 mixtures at ca 600°C. The deposition reactions of carbon from the CO, H2, and CO2 equilibria are well known (Wagman et al, 1945) and well studied. Formation of graphite from CO2 was discussed extensively by Boudouard (1902) and Schenck and Zimmerman (1903), and was known to chemists in France in 1851. We have used a related method, where graphite forms away from the iron, by using a higher temperature, and reduction of CO2 to CO over Zn in the presence of H2 (Jull et al, 1986) as an alternative to the use of Fe alone. The object of this paper is to point out an even simpler graphite preparation system, which eliminates hydrogen. The decomposition reaction of CO (Boudouard, 1902) takes place according to reaction (1).

The number-average molecular weights of beryllium 4-biphenyl(phenyl)phosphinate, di-n-pentylphosphinate, di-n-heptylphosphinate, and trifluoromethyl(phenyl)phosphinate are degraded by the presence of water in toluene. It is proposed that easily hydrolyzable POP bonds contribute, in part, to the bonding of these polymers.

The preparation, properties, infrared, DTA, and TGA data are given for beryllium dimethyl-, tetramethylene-, di-n-butyl-, di-n-pentyl-, di-n-heptyl-, methylphenyl-, diphenyl-, and bispentafluorophenylphosphinates. Synthesis of dimeric beryllium acetylacetonyl phenyl-[o-methylcarboranyl (B10)] phosphinate is reported. The beryllium phosphinates were prepared by the reaction of beryllium acetylacetonate with the appropriate phosphinic acid.

The utility of circul ating mucins as breast cancer markers was first proposed by Ceriani, et al. (1) and was rapidly confirmed and expanded by many other laboratories, including those of Chu, Taylor-Papadimitriou, Hilgers and Kufe (2–5). The antibodies used in mucin assays measure epitopes expressed on or cross-reactive with the human milk-fat globule membrane (HMFG) antigens. Assays using antibodies developed in many of the above mentioned laboratories are now commercially available, and have been used with some success in moni tori ng breast cancer patients.