Noble metal nanoparticles for biosensing applications,
c}alo Doria, Gon{\c, Conde João, Veigas Bruno, Giestas Leticia, Almeida Carina, c}ão Maria Assun{\c, Rosa João, and Baptista {Pedro V. }
, Sensors, feb, Volume 12, Number 2, p.1657–1687, (2012)
AbstractIn the last decade the use of nanomaterials has been having a great impact in biosensing. In particular, the unique properties of noble metal nanoparticles have allowed for the development of new biosensing platforms with enhanced capabilities in the specific detection of bioanalytes. Noble metal nanoparticles show unique physicochemical properties (such as ease of functionalization via simple chemistry and high surface-to-volume ratios) that allied with their unique spectral and optical properties have prompted the development of a plethora of biosensing platforms. Additionally, they also provide an additional or enhanced layer of application for commonly used techniques, such as fluorescence, infrared and Raman spectroscopy. Herein we review the use of noble metal nanoparticles for biosensing strategies-from synthesis and functionalization to integration in molecular diagnostics platforms, with special focus on those that have made their way into the diagnostics laboratory.
RNA quantification using noble metal nanoprobes: Simultaneous identification of several different mrna targets using color multiplexing and application to cancer diagnostics,
Conde, João, c}alo Doria Gon{\c, {de la Fuente} {Jesus M. }, and Baptista {Pedro Viana}
, Nanoparticles in Biology and Medicine: Methods and Protocols, aug, United States, p.71–87, (2012)
AbstractNanotechnology provides new tools for gene expression analysis that allow for sensitive and specific characterization of prognostic signatures related to cancer. Cancer is a multigenic complex disease where multiple gene loci contribute to the phenotype. The ability to simultaneously monitor differential expression originating from each locus allows for a more accurate indication of degree of cancerous activity than either locus alone. Metal nanoparticles have been widely used as labels for in vitro identification and quantification of target sequences. Here we describe the synthesis of nanoparticles with different noble metal compositions in an alloy format that are then functionalized with thiol-modified ssDNA (nanoprobes). We also show how to use such nanoprobes in a non-cross-linking colorimetric method for the direct detection and quantification of specific mRNA targets, without the need for enzymatic amplification or reverse transcription steps. The different metals in the alloy provide for distinct absorption spectra due to their characteristic plasmon resonance peaks. The color multiplexing allows for simultaneous identification of several different mRNA targets involved in cancer development. Comparison of the absorption spectra of the nanoprobes mixtures taken before and after induced aggregation of metal nanoparticles allows to both identify and quantify each mRNA target. We describe the use of gold and gold:silver-alloy nanoprobes for the development of the non-cross-linking method to detect a specific BCR-ABL fusion gene (e.g., e1a2 and e14a2) mRNA target associated with chronic myeloid leukemia (CML) using 10 ng μL -1 of unamplified total human RNA. This simple methodology takes less than 50 min to complete after total RNA extraction with comparable specificity and sensitivity to the more commonly used methods.
Noble metal nanoparticles applications in cancer,
Conde, João, c}alo Doria Gon{\c, and Baptista {Pedro Viana}
, Journal of drug delivery, Volume 2012, p.751075, (2012)
AbstractNanotechnology has prompted new and improved materials for biomedical applications with particular emphasis in therapy and diagnostics. Special interest has been directed at providing enhanced molecular therapeutics for cancer, where conventional approaches do not effectively differentiate between cancerous and normal cells; that is, they lack specificity. This normally causes systemic toxicity and severe and adverse side effects with concomitant loss of quality of life. Because of their small size, nanoparticles can readily interact with biomolecules both at surface and inside cells, yielding better signals and target specificity for diagnostics and therapeutics. This way, a variety of nanoparticles with the possibility of diversified modification with biomolecules have been investigated for biomedical applications including their use in highly sensitive imaging assays, thermal ablation, and radiotherapy enhancement as well as drug and gene delivery and silencing. Here, we review the available noble metal nanoparticles for cancer therapy, with particular focus on those already being translated into clinical settings.