Letheby, Henry

Another cause of concern in the nineteenth century was food adulteration, especially the addition of colouring materials. In 1851 The Lancet set up the Analytical Sanitary Commission, whose main members were Arthur Hassall and Henry Letheby. The reports of the Commission showed that food was indeed being contaminated by poisonous additives. These findings led to the first Food and Drugs Act of 1860, and from the 1870s Local Authorities started to appoint public analysts.349... 

Henry Letheby, a lecturer in chemistry and toxicology at the College of London Hospital, obtained a partially conducting material in 1862 by the anodic oxidation of aniline in sulfuric acid. The material Letheby synthesized was a form of polyaniline. In the 1980s, the New Zealander Alan MacDiarmid of the University of Pennsylvania reinvestigated polyaniline, which is now a widely used conducting polymer. Polyaniline exists in a variety of oxidation states (Figure 27.12), each with different... 

Although conducting polymers are known as new materials in terms of their properties, the first work describing the synthesis of a conducting polymer was published in the ninetieth century. In 1862, Henry Letheby prepared polyaniline by anodic oxidation of aniline, which was conductive and showed electrochromic behavior. However, electronic properties of so called aniline black were not determined. 

As in many other cases in the history of science, there were several precursors to this discovery, including theoretical predictions made by physicists and qnantum chemists, and different conducting polymers that had already been prepared. For instance, as early as 1862, Henry Letheby prepared polyarriline by the anodic oxidation of aniline, which was condnctive and showed electrochromic behavior [9],... 

Functional polymers appeared in the second half of the twentieth century. Although polyaniline was first described in the mid-nineteenth century by Henry Letheby and polypyrrole derivatives were reported to be electrically conducting in 1963 by B.A. Bolto et al. (1963), substantial progress was not made with intrinsically conducting polymers until the pioneering work of Hideki Shirakawa, Alan J. Heeger, and Alan MacDiarmid who reported similar high conductivity in oxidized iodine-doped polyacetylene in 1977 (Shirakawa 1977). For this research, they were awarded the 2000 Nobel Prize in Chemistry for the discovery and development of conductive polymers. ... 

Henry Letheby, a lecturer in chemistry and toxicology at the College of London Hospital, obtained a partially conducting material in 1862 by the anodic oxidation of aniline in sulfuric... 

Polyanitine was the first CP polymer, which was described in the mid-19th century by Henry Letheby [36]. Since then numerous intrinsically CP have been developed, among others polyacetylene, polythiophene, polypyrrole. CPs, also referred to as synthetic metals, have found applications in many fields. They are integrated for example in solar cells, rechargeable batteries and biomedical devices [37]. CPs are also very attractive for biosensors. In biosensors, CP can be used as excellent non-metallic electrodes. Numerous biosensors have been developed over the past 20 years with electrodes made of CP. The fabrication is fairly easy and flexible. This allows the biosensors to be single-use system avoiding any risk of contamination and adaptation of the biosensors to new targets can be rapidly made. They are mostly biocompatible, can easily be synthesized and can be modified for immobilization of bioelements [38]. These conductive polymers are referred to as intrinsic conductive polymers in comparison to extrinsic conductive polymers that are a polymer matrix in which some metal particles have been entrapped [39]. 

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