[pharma]

I am a QC analyst who works in pharma industry and we use to prepare Ringer lactate solution (which is an intravenous solution) that should have an osomolarity value of 278 mOSM/L, we have been doing that for the last two years and we never had any problem with the assay analysis or the osomolarity, but in the last week we prepared a preparation that had an osomolarity value of 300 mOSM/L although the assay for all the components were within range and within the historical trend. we concluded that the increase of osomolarity is due to an addition of some material by mistake or somthing related to the water used for prepration, when we checked the records we found that the materials were added exactly and that there was no problem with water as indicated by the conductivity value which was less than 1.0 microsemins during water filling. We have been trying to understand what happened but we could not find a solution, any body has any suggestions?

BTW, the materials used for preparation of Ringer is
1) NaCl.
2) Potasuim chloride.
3) Calcium chloride.
4) Soduim lactate.
 

[Borek]

I don't think anybody will be able to help here - I mean, there are so many possible sources of mistake that it is impossible to rule them out sitting 5000 km from you

First of all - try to prepare another solution, check if it is OK. Could be it was just a human error, if so, new solution should be OK.

If the problem persist you have no choice but to check if all solutions used follow specifications.

[pharma]

I don't think anybody will be able to help here - I mean, there are so many possible sources of mistake that it is impossible to rule them out sitting 5000 km from you

First of all - try to prepare another solution, check if it is OK. Could be it was just a human error, if so, new solution should be OK.

If the problem persist you have no choice but to check if all solutions used follow specifications.

yes but it was a 12,000 Litre preparation that was destroyed after being filled in bottles (24,000 bottle were rejected) and we dont know yet the reason, I want some expert to tell me if the source of this extra osomolarity could be an added material by mistake or something happned for the solution it self.

[Train]

Did you run suitability tests with osmolarity standard to make sure your instrument was working properly?

[pharma]

Did you run suitability tests with osmolarity standard to make sure your instrument was working properly?

yes and it is working properly.
what could affect the osomolarity of Water because may be it is the problem.

[Borek]

Anything soluble added will change osmolality. If water had correct resistivity it could be contaminated with some non-electrolyte.

For such an amount of preparation it has to be some serious mistake. If my calculations are correct you you need about 7.8 kg of excess NaCl.

Have you done analysis of the samples of the wrong solution, to check concentration of cations?

Could be someone weighted wrong amounts of solids - switched masses of CaCl₂ and NaCl, or NaCl and KCl, or mistakenly used the same mass twice for two different solids. Cation analysis will tell you in an instant if that's the case.

[Borek]

Anything soluble added will change osmolality. If water had correct resistivity it could be contaminated with some non-electrolyte.

1) we performed a complete re-analysis for all the elements and all of them were on target, so the ammounts added are correct.

2) We suspected that a foreign material was added and made analysis for every think we suspected that is available in the manufacturing room or the raw material  warehouse but found nothing.

Electrolytes are those substances that get dissociated to ions - and ions are the conducting medium in solution. They also change osmolality of the solution.

Non-electrolytes are substances that don't dissociate - like sucrose or ethanol. They don't change conductivity of the water, but they change the osmolality.

So, if your coductivity was correct, but osmolality was wrong, it could mean some non-electrolyte was present.