Abstract A new GC-MS method is developed for the determination of formaldehyde. Formaldehyde exposure to the food materials may lead to its migration into food. The formaldehyde is reported to be toxic to human health if taken or exposed in higher than recommended quantity. This papers reports analytical method to get the information about the content of the formaldehyde in the kitchenware. Prior to the determination process, simulation study was performed to get the information about the migration of formaldehyde. Method was applied to the real samples for formaldehyde determination. It has been observed that the all the simulated real sample witnessed migration of formaldehyde from the kitchenware. Alongside the validation study was performed too, which suggest that the method is linear in the concentration range of 2.5 to 30 mg l-1. The precision study suggests a % RSD in the range of 0.568- 3.77 for all concentration points. The recovery study highlights an excellent recovery of the method which was found in the range of 97.64-99.43%. LOD and LOD of the method was found to be 0.35 and 1 ml l-1, which is equivalent to 0.05 and 0.142 mg l-1 of formaldehyde, respectively.

This study was aimed at employing response surface methodology (RSM) for optimization of process variables and identifying optimal conditions for the adsorption of bromate (BrO3-) from contaminated water using multi-walled carbon nanotubes, based on iron hydr(oxide), Fe-CNTs nanocomposite. Fifteen experimental runs were conducted in batch mode to study the effect of individual as well as interactive process variables, i.e., pH, BrO3- initial concentration, and adsorbent dose, on the removal of BrO3- using Box-Behnken design (BBD) of RSM. The coefficient of determination (R²) at 98.34% indicated a good agreement between actual and predicted values. The main effect and contour plot were drawn to obtain the independent and interactive effect of operational variables on BrO3- uptake. A process optimization curve was drawn to determine the optimum operating conditions that lead to a desirable response. The optimum conditions for BrO3- adsorption using Fe-CNTs nanocomposite were found to be pH 2.0, initial BrO3- concentration of 10.0 mg/L, and adsorbent dose of 0.010 g per 50 mL solution.

ABSTRACT: Two analytical methods were developed, one utilizing sensitive UPLC-MS/MS method while other being the spectrophotometric method exploiting the Dushman reaction. Both methods were validated based on ICH guidelines and were successfully applied to quantitate the drug in marketed formulation. UPLC-MS/MS method responded linearly in the range of 1.6 µgmL-1-6.4 µgmL-1 while spectrophotometric procedure followed the Beer’s law in the concentration range of 30-100 µgmL-1. UPLC-MS/MS has been found to have a limit of quantitation of 0.97 µgmL-1 while spectrophotometric method was found to quantitate 14.00 µgmL-1 correctly with high precision. Both the methods showed an excellent recovery of 99.36%-100.91% (% RSD 1.05-1.73) and 98.64%-99.73% (%RSD 0.67-1.68) for UPLC-MS/MS and spectrophotometric, respectively.

Abstract Twenty-nine Yemeni honey samples were analyzed to determine total phenolic and flavonoid contents using Folin-Ciocalteu and spectrophotometric technique. These tested honey samples were collected from different regions corresponding to various floral species: jujube, cactus and multifloral plants. Folin-Ciocalteu method was adopted for the analysis of total phenolic and flavonoid contents. Gallic acid and quercetin were considered as the best standards as the spectrophotometric response of these compounds are equivalent to most other phenolic acids and flavonoid compounds, respectively. The obtained results of honey samples were in a wide range; the highest phenolic acid concentration was obtained for honey produced from cactus, while the lowest value corresponded to monofloral honey from jujube. On the other hand, a broad variation was also observed in total flavonoid content; the highest value was obtained for honey collected from cactus area (S4) and the lowest value was found in honey produced from multifloral plants (A1).

A kinetic spectrophotometric method based on the initial rate measurement has been developed for the determination of N-acetyl L-cysteine. The developed method is based on the oxidation of N-acetyl L-cysteine with iodate. The reaction product was studied and characterized using the mass spectrometry and the structure of the product was proposed. From the mass spectrometric studies it was concluded that the oxidation of the drug resulted in the formation of a disulfide. The developed method was validated as per the guidelines of international conference on harmonization. The developed initial rate method was found to be linear in the concentration range of 1.25 - 30 µg ml-1. The detection and quantitation limits were found to be 0.018 and 0.056 µg ml-1. In the current study, the degradation product of N-acetyl L cysteine was also prepared and identified using mass spectrometry.