Simultaneous determination of rutin and ascorbic acid in a sequential injection lab-at-valve system.

A green, simple, accurate and highly sensitive sequential injection lab-at-valve procedure has been developed for the simultaneous determination of ascorbic acid (Asc) and rutin using 18-molybdo-2-phosphate Wells-Dawson heteropoly anion (18-MPA). The method is based on the dependence of the reaction rate between 18-MPA and reducing agents on the solution pH. Only Asc is capable of interacting with 18-MPA at pH 4.

Dyspnea-12-Arabic: testing of an instrument to measure breathlessness in Arabic patients with chronic obstructive pulmonary disease.

Objective: The aim of this study was to develop the Dyspnoea-12-Arabic (D-12-A) questionnaire and test its reliability and validity for the assessment of breathlessness in Arabic speaking patients with chronic obstructive pulmonary disease (COPD) in Jordan.

Background: Breathlessness is a complex multidimensional symptom which incorporates physiology and psychology.

Methods: The D-12-A, Hospital Anxiety and Depression Scale (HADS), and Quality of Life Index pulmonary version (QLI-P) were completed by 67 Jordanian patients with COPD.

Highly sensitive sequential injection determination of p-aminophenol in paracetamol formulations with 18-molybdodiphosphate heteropoly anion based on elimination of Schlieren effect.

A highly sensitive, precise and automated method using sequential injection analysis to assay quantitatively low levels of the p-aminophenol (PAP) in paracetamol formulations has been developed. A solution containing PAP and paracetamol is injected into an acetate buffer carrier stream and merged on-line with 18-molybdodiphosphate heteropoly complex reagent to form a specific blue derivative that is subsequently detected spectrophotometrically at 820nm. The procedure has been optimized mainly with respect to measurement sensitivity.

Sequential injection determination of orthophosphate as ion associate of 12-molybdophosphate with Astra Phloxine.

A simple and fast reaction between 12-molybdophosphate heteropoly anion and the polymethine dye Astra Phloxine was used for the development of a new SIA method for the determination of orthophosphate. The suggested method has higher sensitivity and a broader calibration range than existing SIA methods. It can be used to detect phosphate in the range from 0.