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The syntheses, in vitro antituberculosis and cytotoxic activities of cyclotetraphosphazenes were investigated.

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Nanoparticles of noble metals, especially the silver nanoparticles, have been widely used in different fields of science. Their unique properties, which can be incorporated into biosensor materials, composite fibers, cosmetic products, antimicrobial applications, conducting materials and electronic components, make them a very important subject to be studied by chemistry, biology, healthcare, electronic and other related branches. These unique properties depend upon size and shape of the silver nanoparticles. Different preparation methods have been reported for the synthesis of the silver nanoparticles, such as electron irradiation, laser ablation, chemical reduction, biological artificial methods, photochemical methods and microwave processing. This chapter aims to inform the synthesis methods of the silver nanoparticles.

A new reversed-phase ultraperformance liquid chromatography method with a photodiode array detector was developed for the quantification of ascorbic acid (AA) and caffeine (CAF) in 11 different commercial drinks consisting of one energy drink and 10 ice tea drinks. Separation of the analyzed AA and CAF with an internal standard, caffeic acid, was performed on a Waters BEH C column (100 mm × 2.1 mm, 1.7 μm i.d.), using a mobile phase consisting of acetonitrile and 0.2M HPO (11:89, v/v) with a flow rate of 0.25 mL/min and an injection volume of 1.0 μL. Calibration graphs for AA and CAF were computed from the peak area ratio of AA/internal standard and CAF/internal standard detected at 244.0 nm and 273.6 nm, respectively. The developed reversed-phase ultraperformance liquid chromatography method was validated by analyzing standard addition samples. The proposed reversed-phase ultraperformance liquid chromatography method gave us successful results for the quantitative analysis of commercial drinks containing AA and CAF substances.

A nanostructured silver-aniline modified pencil electrode obtained by applying experimental design and optimization was developed for the differential pulse stripping voltammetric quantification of acetaminophen in the pharmaceutical products, tablet and syrup. The electrode development process was performed by the modification of PGE with aniline using CV procedure and the reduction of silver nanoparticle on the polyaniline modified PGE. As a result, a new electrode system consisting of a nanostructured silverpolyaniline modified pencil graphite electrode (AgNS-PA-PGE) was obtained to reach a well-defined and higher peak current for the analysis of the related drug. The calibration curve was found linear in the range of 5 × 10 −8 -8 × 10 −7 M for acetaminophen. The validity and applicability of the proposed voltammetric method was tested by analyzing independent validation samples. It was observed that the proposed voltammetric approach for the real tablet and syrup samples gave successful analysis results.

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In this study, two kinds of compounds, namely, mono‐ferrocenyl‐2‐cis‐4‐dichloro‐ansa‐ (2,4‐ansa; 3) and mono‐ferrocenyl‐spiro‐ (spiro; 4) hexachlorocyclotetraphosphazenes, were obtained by the Cl replacement reaction of N4P4Cl8 (1) with an equimolar amount of sodium 3‐(N‐ferrocenylmethylamino)‐1‐propanoxide (2). The reactions of 2,4‐ansa (3) with excess diamines and dialkoxides resulted in the formation of ansa‐cyclotetraphosphazenes (3a–3e). Spiro (4) was reacted with excess diamines and dialkoxides to give the mono‐ferrocenyl‐spiro‐cyclotetraphosphazenes (4a–4d). Although 2,4‐ansa (3) produced the dispiro (3a) with N‐(4‐fluorobenzyl)‐N′‐methylethane‐1,2‐diamine, it afforded both monospiro (3b) and dispiro (3c) with N‐(4‐fluorobenzyl)‐N′‐methylpropane‐1,3‐diamine. However, spiro (4) yielded a trispiro (4a) with N‐(4‐fluorobenzyl)‐N′‐methylethane‐1,2‐diamine and 2,6‐dispiro (4b) with N‐(4‐fluorobenzyl)‐N′‐methylpropane‐1,3‐diamine. The structures of the phosphazenes were elucidated by FTIR, ESI‐MS and/or HRMS, spectroscopic and crystallographic (for 3f and 4b) data. Furthermore, the electrochemical findings of cyclotetraphosphazenes exhibited electrochemically reversible one‐electron oxidation of Fe‐redox centre. As an example, the chirality of 3c was investigated by 31P NMR spectroscopy on the addition of (R)‐(+)‐2,2,2‐trifluoro‐1‐(9′‐anthryl)‐ethanol, chiral solvating agent (CSA). The circular dichroism (CD) (for 3d and 3e), HPLC (for 3d, 3e and 3f) and X‐ray (for 3f) display that these compounds have chirality (RS′ or SR′) in the solution and solid state. This paper also focuses on the antimicrobial activities, the interactions with pBR322 DNA, in vitro anticancer activity against L929 fibroblast and MCF7 breast cells, and antituberculosis activity against Mycobacterium tuberculosis H37Rv of the cyclotetraphosphazenes.