High-end spectrophotometric analytical instruments are typically employed in academic institutions and industrial research laboratories and are rarely available for experimenters or younger students. An affordable high-tech robotic product manufactured by Lego may be employed as a single-beam monochromatic light source, detector and display to demonstrate and investigate the Beer-Lambert law us...

A derivative spectrophotometric method was developed to determine NO3(-)-N in plant tissues. The method is based on measurement of the first-derivative spectrum of nitrosalicylic acid in basic solution. The nitrosalicylic acid was obtained by reaction of samples with salicylic acid in concentrated sulfuric acid and was used by Cataldo et al. in nonderivative spectrophotometry. The main strength...

Although there are numerous methods for quantitative determination of antioxidative vitamins: C, E, and A, there are no methods favourable for the broadly understood analytic practice – they have various faults and limitations or require expensive apparatus. Therefore, we have elaborated modifications of valuable spectrophotometric methods for determination each of those vitamins, which origina...

A method comparison study for estimation of serum Calcium and Phosphorus levels and their alterations in CKD (Chronic Kidney Disease) patients was done. Serum Calcium was estimated by O-cresolphthalein complexone spectrophotometric method and NM BAPTA autoanalyzer method. Serum Phosphorus was estimated by the Gomorri’s spectrophotometric method and Phosphomolybdate UV autoanalyzer method. The n...

This paper describes separate spectrophotometric procedures for rapidly measuring carboxyhemoglobin (COHb) and methemoglobin (MetHb) in blood. Absorbance measurements are made in the Soret region at a blood dilution near 1000-fold. For COHb estimation, the diluent contains sodium hydrosulfite, providing the two-component system COHb--Hb for absorbance measurements at 420 and 432 nm. The NA2S2O4...

The spectrophotometric determination of the oxygen consumption of biological samples with Hb02 as oxygen donor and’indicator [ 1,2] has the advantage over conventional methods of being accurate, sensitive and suitable for automation [3,4]. Since interferences due to the erythrocyte enzymes are usually negligible, highly purified hemoglobin preparations are not generally required [5-81. However,...

In this work, a solid phase spectrophotometric method in association with flow injection analysis for formaldehyde determination has been developed with direct measurement of light-absorption in C(18) material. The 3,5-diacetyl-1,4-dihydrolutidine produced from the reaction between formaldehyde and fluoral P was quantitatively retained on C(18) support and the spectrophotometric detection was p...

A simple and rapid spectrophotometric method has been developed for the determination of Pu in highly radioactive liquid waste. This method uses Nd(III) as an internal standard, which enables us to determine the concentration of Pu and to authenticate the whole analytical scheme as well. A Nd(III) standard mixed with a sample solution and Pu was quantitatively oxidized to Pu(VI) with Ce(IV) in ...

An instrument interface which generates an output voltage level proportional to rate of change of an input voltage is described. The interface permits direct connection of routine spectrophotometric rate measurements to a real-time laboratory computer system. The form of the voltage level output enables the computer to read rates in the same manner as peaks are read for AutoAnalyzers, permittin...

A rapid, relatively sensitive, and low-cost method for the determination of water-soluble urea content in dermatological therapy products and cosmetics is proposed using a new spectrophotometric assay with water as the only extraction solvent. Spectrophotometric methods involve addition of a known excess of bromate to urea in an acid medium, followed by the determination of residual bromine and...