Application of thin metal film elements in bioanalysis

Abstract

Advanced metal deposition and microfabrication techniques enable preparation of metal surfaces with high precision and excellent control over their size and shape with subnanometer resolution. Thin metal films of different types and functions can be found in many analytical instruments. Surfaces with high optical quality serve as mirrors, beam splitters, antireflective coatings etc. Smooth metal coating is crucial in electron microscopy. Unique properties of the thin metal films are widely used in optical systems, as tools for sample manipulation but also for chemical sensing and detection. While some of the applications are widespread and belong to the basic curriculum in analytical chemistry, the newer or less common uses of thin metal films are well known only to the experts in the field. The purpose of this critical review is to highlight the role of thin metal films in bioanalysis and summarize some of their main applications in current bioanalytical instrumentation.

Electrodeposition of Silver Amalgam on Thin Gold Film Electrodes for Voltammetric Detection of 4‐Nitrophenol and DNA Labeled with Osmium Tetroxide‐Bipyridine Complex

“…Metal nanoparticles can be used for: i) immobilization or labeling of biomolecules; ii) catalysis of electrochemical reactions; iii) enhancement of electron transfer; and iv) they can act as reactants/agents, e. g. antibacterial, antifungal, antiviral, anti‐inflammatory, anti‐angiogenic, and anti‐cancer . A very promising application for nanotechnology consists of micro‐ or even nano‐ electrode array fabrication in combination with high throughput microfluidic or “lab‐on‐chip” systems , which might be combined with electrochemical, optical (e. g. fluorescence, Raman, surface plasmon resonance (SPR) spectroscopies) or even spectroelectrochemical (UV/VIS, electrochemiluminiscence) detection. Metal mercury and silver nanoparticle attributes might be advantageously combined to provide sufficient mechanical stability for the material and to enable novel possibilities for fabricating nanostructured silver amalgam electrode arrays or other sensing design with promising electrochemical and spectroscopic properties.…”

Metal nano‐film resistivity chemical sensor

“…However, as the thickness of the metal layer decreases, the contribution of the electrons close to the surface to the total conductivity of the material increases and their mobility and scattering depends on the surface interactions. While this effect has been theoretically described over 60 years ago , only few papers have investigated the effect experimentally and to our knowledge there is no work describing a practical application of a simple thin metal sensing probe except to our previous report on the free floating nanoelectrodes for electrochemiluminiscence generation .…”

Synthesis of monodisperse silica microspheres and modification with diazoresin for mixed-mode ultra high performance liquid chromatography separations

“…Great attention has been given to silica particles during the past few decades due to its extensive application in various fields such as pharmacy , electronic and thermal insulators , antireflective coating materials , cosmetics , and diagnostic substances . Since different silica particle sizes make a great difference in its physical, electrical, and optical properties, it is necessary to pay special attention to the effective methods for preparing silica particles with low polydispersity (PDI).…”

“…Great attention has been given to silica particles during the past few decades due to its extensive application in various fields [1][2][3][4][5][6][7][8] such as pharmacy [2], electronic and thermal insulators [3], antireflective coating materials [4], cosmetics [5,6], Among various types of particles used for packing materials, the modified silica particles have almost been the most widely used stationary phase for chromatographic separation due to some advantageous characteristics, such as a relatively high specific surface area, narrow particle size distribution, and good mechanical stability [18,19]. However, the modification process of silica particles is usually complicated which contains multiple time-consuming steps such as silica pretreatment, introducing coupling agent, and inserting target coating reagents.…”