Reduction of spectral interferences using ultraclean gold nanowire arrays in the LDI-MS analysis of a model peptide.

The surface chemistry of gold nanowires (AuNWs) has been systematically assessed in terms of contamination and cleaning processes. The nanomaterial's surface quality was correlated to its performance in the matrix-free laser desorption ionization mass spectrometry (LDI-MS) analysis of low molecular weight analytes. Arrays of AuNWs were deposited on glass slides by means of the lithographically patterned nanowire electrodeposition technique. AuNWs were then characterized in terms of surface chemical composition and morphology using X-ray photoelectron spectroscopy, scanning electron microscopy and atomic force microscopy. AuNWs were subjected to a series of well-known cleaning procedures with the aim of producing the best performing surfaces for the LDI-MS detection of leucine enkephalin, chosen as a model analyte with a molar mass below 1,000 g/mol. Prolonged cyclic voltammetry in 2 M sulfuric acid and, most of all, oxygen plasma cleaning for 5 min provided the best results in terms of simpler (interference-free) and more intense mass spectrometry spectra of the reference compound. The analyte always ionized as the sodiated adduct, and leucine enkephalin limits of detection of 0.5 and 2.5 pmol were estimated for the positive and negative analysis modes, respectively. This study points out the tight correlation existing between the chemical status of the nanostructure surface and the AuNW-assisted LDI-MS performance in terms of reproducibility of spectra, intensity of analyte ions and reduction of interferences.

Silver nanofractals: electrochemical synthesis, XPS characterization and application in LDI-MS.

Silver nanofractals (Ag-NFs) have been electrosynthesized and characterized by means of morphological and spectroscopic analytical techniques. In particular, X-ray photoelectron spectroscopy has been used to assess the nanomaterial surface chemical state. Ag-NFs show interesting perspectives in bioanalytical applications, particularly as non-conventional desorption and ionization promoters in laser desorption ionization mass spectrometry.

Hospital librarians and the Medical Library Association.

Hospital librarians have been active participants in and contributors to the Medical Library Association since it was founded. This article reviews the history of the Hospital Libraries Section and provides some personal observations on the contributions the association has made to hospital librarians and their growing influence on the association.

Peer review in journals indexed in Index Medicus.

OBJECTIVE: To determine whether peer review policies are published in English-language journals indexed in Index Medicus and, secondarily, to obtain information on the peer review practices of such journals. DESIGN: Examined one issue of a sample of all journal titles written in English and indexed in Index Medicus, and all indexed English-language journals in four subject fields. A questionnaire was sent to the editors of journals in the subject fields requesting information on their peer review practices. SETTING: Journals received at the National Library of Medicine. PARTICIPANTS: Editors of journals in four subject fields. MAIN OUTCOME MEASURE: Existence of a printed statement of the peer review process for manuscripts. RESULTS: Although the editors queried in the four subject fields indicated that overall, 56% to 65% of the articles were peer reviewed, clear statements about their peer review practices were not found in half of their journals or in the overall sample. CONCLUSIONS: Editors should publish clear statements of the peer review process followed for each type of article published in their journals.

That vision thing.

The 1991 Janet Doe lecturer describes the vision held by the founders of the Medical Library Association of medical information being readily accessible to health professionals no matter how far they were located from major medical centers, and traces the pursuit of this vision to current outreach activities.

Where there is no vision the people perish.

Forces are already in motion that will change the future of health sciences librarianship. In addition to changes in academic health centers, changes in the publishing industry, the mode of delivering information by librarians, the use of computers to manipulate and make information available, the user's access to information, and communications technology are briefly described. The author proposes that health sciences librarians can participate in the creative process of constructing their professional future by being informed, expanding cooperative efforts, planning, ceasing a romanticized view of the profession, and becoming achievers rather than sustainers.