Raman spectroscopy as a new biochemical diagnostic tool

In this review, Raman spectroscopy is described as a new and potentially powerful diagnostic tool in comparison to routine biochemical tests. Advanced instrumentation and new Raman spectroscopy techniques enable rapid and simultaneous identification and/or determination of se veral biochemical parameters, such as glucose, acetone, creatinine, urea, lipid profile, uric acid, total protein, etc, with a very low limit of detection. Raman spectroscopy could also be applied in molecule and cell characterization, as well as diagnostics of atherosclerosis in its early stage. Raman spectroscopy is nondestructive and could be applied to all kinds of samples, which simplifies the diagnostics of numerous disea ses and pathologic states. Special attention is paid to literature data illustrating the application of Raman spectroscopy for transdermal glucose monitoring and cancer diagnostics

Zinc complex-based determination of rutin in dietary supplements

The aim of this study was to develop and validate a simple, rapid, sensitive and low-cost method for determination of rutin in tablets. The proposed spectrophotometric method is based on the formation of the Zn2+-rutin complex in methanol 70% (v/v) at pH 8.52, and detection at λmax= 410 nm. The concentration range over which the response was linear was 0.3-12.2 μg ml-1. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.21 μg ml-1 and 0.63 μg ml-1, respectively. The proposed method was successfully applied to the determination of rutin in herbal dietary supplements. The reliability of the method was checked by comparison with results obtained by the established RP-HPLC/UV method. The proposed method fulfills all aimed requirements

Determination of flavonoids and total polyphenol contents in commercial apple juices

© 2018 Czech Academy of Agricultural Sciences. All Rights Reserved. We propose a sensitive and selective spectrofluorimetric method for the determination of flavonoids as expressed in 'quercetin equivalent' in apple juices. The method is based on the strong emission of the aluminium(III)-quercetin complex at 480 nm with excitation at 420 nm, and it is successfully applied for the determination of flavonoids in commercial apple juices and compared with results obtained in reference spectrophotometric determination. The flavonoid content in commercial apple juices was found to range from 5.53 to 15.55 mg/l quercetin equivalent. The very good agreement between the two methods indicates the suitability of the proposed spectrofluorimetric method for the precise and accurate determination of flavonoids. In addition, the total polyphenol content was determined spectrophotometrically using the Folin-Ciocalteu (FC) method and the antioxidative activity of the tested juices was tested in a DPPH assay and these values were correlated with each other. The obtained profiles of compounds with antioxidative ability lead us to conclude that fruit juice labels based only on fruit % might sometimes misinform consumers

A spectroscopic investigation of 12-tungstophosphoric acid alkali salts

In this paper the latest results of our continuing investigation of heteropoly acids and their salts are reported. Specially attention was paid to the influence of cations on the dynamic equilibrium of protonic species, as well as on the structure of the host lattice itself, i.e., the Keggin anions. The investigations were done by IR and Raman spectroscopy within the range of 1200-40 cm-1