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Small uncertainty is achieved through precision measurement approaches using the high performance, for cobalt and phosphorus by both ICPOES and IC.Nitrate CRM was used for making matrix matched calibrant used for IC analysis.Cadmium lowpressure discharge microwave lamp was used as the UV source.Each quartz vessel and its corresponding lamp were treated like a unit to avoid any contamination.The sample and calibrant preparations were carried out as per high performance methodology for ICPAES and IC.Briey, HP methodology employs a careful experimental comparison of a sample with a calibration standard, that is prepared to mimic the expected nature of the sample in terms of both matrix and analyte mass fraction.Germanium, scandium and bromide were used as internal standards for the ICPAES and IC measurements respectively to compensate for short term noise and a dri <a href="http://www.targetmol.com/compound/Lansoprazole"></a> correction procedure, to correct for long term noise.In the case of determination of free cobalt by IC, HP methodology was not used.The microwave heating programme was watt for min followed by watt for min and then allowed to cool to room temperature.The digestion solution was transferred into a PFA vial for IC measurement.Three blanks were prepared containing only the reagents required for photolysis. Sample preparation for free cobalt determination.However considering the basic eluent that is normally used for the separation of phosphate in IC, conventional MW assisted acid digestion could not be used, as the low pH of the resulting digest can cause disruption of the multiple ion exchange equilibrium existing between the eluent species and the column, leading to severe base line perturbations.Additionally, for the digestion the organophosphorus compound, hydrochloric acid is necessary and photooxidative mineralization, requires additional oxidants like hydrogen peroxide.So a MW based UV digestion was optimised where mineralization is usually achieved using much lesser quantity of dilute acid.Multiple digestion experiments were carried out with intentionally low quantity of hydrochloric acid with increasingly varying amount of hydrogen peroxide as the later reagent decomposes into water and as a result the digest is better suited for suppressed conductivity detection of phosphate by IC.However, it was seen that with the increase of hydrogen peroxide, the phosphate peak height increased correspondingly.Two millilitre of AR grade hydrogen peroxide contributes to blank values of mg of phosphate. Even using suprapur grade HO, the blank values for phosphate were in the range of mg of phosphate.Phosphates and pyrophosphates are oen added as stabilizers to various grades of hydrogen   peroxide, which contributes to the process blank.To circumvent this blank problem, sodium perborate was used that produced in situ hydrogen peroxide and the blank levels for phosphate were reduced by a factor times, compared to the blank values obtained with AR grade hydrogen peroxide.Set of three solutions were prepared each of that contained identical phosphate and bromide mass fractions in the presence of chloride, mass fractions.These ratios of phosand nitrate mggphate to bromide were compared with the results obtained when no chloride and nitrate were present.The presence of chloride and nitrate at their maximum mass fraction found in the digest, a reduction in the phosphate to bromide peak height ratio was observed.

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