Sciencemadness Discussion Board - Production of pharmaceutical grade (USP, EP, BP, JP) compounds

Production of pharmaceutical grade (USP, EP, BP, JP) compounds

RogueRose - 20-10-2018 at 03:38

I was looking over various natural compounds that are used in pharmaceuticals as well as synthesized compounds and it got me wondering how they go about manufacturing to such tight standards.

Talking NaCl for example which might be the most used compound in medicine for saline, I found that there are relatively few producers of the solution, at least in the US and the process seems like it wouldn't produce "sterile" or pure NaCl solution.

It stated that much of the NaCl used comes from underground mines that are mined via brine solutions so fresh spring water is injected into the mine and a brine solution is drawn up (I'm guessing it is done by densities, more saturated sinks to the bottom?). From there the water is either evaporated or it is diluted with other water for a saline solution. It is mentioned that all the water that goes in comes from a "protected" source as well as where the extract is handled is also a clean area.

I would assume that all the salt isn't pure NaCl in these deposits but probably a high percentage. If they wanted to claim it is USP grade NaCl then how would they extract the contaminates from either the solution or powder?

I would assume that NaCl could be made to a high level of purity starting with Na metal + water to get NaOH then bubble Cl2 through it to get NaCl, though I kind of doubt that is how they produce the salt.

Are there other methods that can produce a very pure product without building the compound from pure elemental blocks?

Tsjerk - 20-10-2018 at 03:52

Why produce when it is already obtainable from natural sources?

Fulmen - 20-10-2018 at 03:55

The production will most likely go through several mfgs. Someone produces technical grades from crude products, others will purify it further to meet more stringent requirements. Purification will depend on contaminates, the first steps will probably be crystallization/precipitation reactions. Sterilizing the product is the simplest step, NaCl can be heated to temperatures that can kill anything living.

Sulaiman - 20-10-2018 at 04:07

Production of USP, EP, BP, JP grades require complete confidence in your suppliers,
or tests as specified by the relevant standard.
If you cannot do the assay there is little point in manufacturing.
If I buy xxP materials I expect a CoA to be available.

For the specific case of sodium chloride,
both sodium and chlorine are commercially obtained at significant cost by
the electrolysis of (a mixture of calcium chloride and) sodium chloride,

[Edited on 20-10-2018 by Sulaiman]

unionised - 20-10-2018 at 04:28

Quote: Originally posted by RogueRose

I was looking over various natural compounds that are used in pharmaceuticals as well as synthesized compounds and it got me wondering how they go about manufacturing to such tight standards.

Talking NaCl for example which might be the most used compound in medicine for saline, I found that there are relatively few producers of the solution, at least in the US and the process seems like it wouldn't produce "sterile" or pure NaCl solution.

It stated that much of the NaCl used comes from underground mines that are mined via brine solutions so fresh spring water is injected into the mine and a brine solution is drawn up (I'm guessing it is done by densities, more saturated sinks to the bottom?). From there the water is either evaporated or it is diluted with other water for a saline solution. It is mentioned that all the water that goes in comes from a "protected" source as well as where the extract is handled is also a clean area.

Are there other methods that can produce a very pure product without building the compound from pure elemental blocks?

Where did you hear that account of making saline?
And yes, there are ways of making pure materials without starting from the elements- which is just as well.
Sodium metal is rather reactive, and difficult to purify.
So making pure NaCl from it wouldn't be practical (and, byw adding Cl2 to NaOH certainly doesn't give you pure NaCl)

The commonest way to purify solids is by recrystallisation.
That's not very effective in the case of NaCl because it has a rather flat solubility curve.
It's generally purified by dissolution followed by precipitation by the addition of HCl(gas).

mayko - 20-10-2018 at 05:51

There are definitely some intermediate steps between brine from the ground and saline IV. World of Chemistry visited an IV plant at one point; check out ~13:30 to see some of the process:

https://www.learner.org/vod/vod_window.html?pid=803

RogueRose - 20-10-2018 at 08:32

Quote: Originally posted by Tsjerk

Why produce when it is already obtainable from natural sources?

Because of the purity needed. If it needs to meet ultra high levels of purity and to make sure there aren't contaminates (like heavy metal salts or other such nasties).

I understand that there are natural sources but I've never seen deposits that are 100% anything, they always have something else in them, though they may be highly pure (95-98%) but that isn't high enough to meet USP standards. How do they remove CaCl2 or KCl, MgCl2 and other chlorides that are often present in large salt deposits.

Would ion exchange resins work for removing various things even if it has to be put through various "steps" (each to remove a different contaminate)?

I only mentioned starting from pure sodium metal because with that you can control the purity of all the starting elements and build from there - but I don't think this would be cost effective.

RogueRose - 20-10-2018 at 08:41

Quote: Originally posted by Sulaiman

Production of USP, EP, BP, JP grades require complete confidence in your suppliers,
or tests as specified by the relevant standard.
If you cannot do the assay there is little point in manufacturing.
If I buy xxP materials I expect a CoA to be available.

?? yeah, that is kind of the point of me asking how they get to the level of purity where it would be certified as pharma grade. I used NaCl as an example b/c it has natural sources (mines, deposits, etc) and could also be made from NaOH from the chlor alkali process - using the NaOH as the compound to purify using varying solubility qualities to remove contaminates - then evaporate off the solvents and chlorinate it.

I could have asked the same question about any other product people take from things like FeSO4, copper supplements/medicines, KCl and many other compounds to actual medicines like tylenol, ibuprofen, anti-depressants, etc. They all have to meet the purity levels and I'm wondering if it is done by many purification steps of an impure product (such as NaCl, KCl, or FeSO4), or if the compound is "built-up" from elemental building blocks which they know are already highly pure.

RogueRose - 20-10-2018 at 08:52

Quote: Originally posted by unionised

I'd have to look back in the internet search history but I'm pretty sure it was Bloomberg when I was researching the reason saline was so darn expensive and why there have been shortages in the US and many other "rich" nations.

do you really need the source or were you just curious. The article blamed the shortage on shady deals between drug manufacturers & pharmacies/insurance companies which use saline as an extortion tool to get insurance companies to cover various drugs they otherwise wouldn't. Then it said there are only a couple US manufacturers of the product - sterile NaCl (morton being one) - but I'm sure there are many "manufacturers" of saline with re-branded products.

Do you have any inside information into this industry by chance? If you do I would like to ask a couple questions.

Are you telling me that by bubbling in HCl gas that the NaCl will "salt out"? I would have suspected that it has a higher solvency in HCl. I do see it has rather low solubility in other solvents while NaOH has fairly good solubility - if you were looking to purify through solvent recrystalizations.

Yeah I definitely mis-spoke when I said "adding Cl2 to NaOH" I should have said HCl.

RogueRose - 20-10-2018 at 09:01

mayko - thank you for the link!

I have also read from different sources what the standard is for USP grade water and some just mention Distilled or RO water and then some mention Ultra-pure water (basically water that isn't conductive and has a VERY high resistance due to lack of anything buy H2O - about 18.18 million ohms resistance).

In some articles I've read regular distilled or "double distilled" water is used but some newer links in Wiki have stated that ultra pure water is required for USP spec. I find this somewhat hard to believe that UPW would be needed as the "lesser" quality has been used for decades without issue.

Tsjerk - 20-10-2018 at 09:53

Ultra pure water is not that expensive, it comes from the tap on every biology lab.

happyfooddance - 20-10-2018 at 10:09

There are a lot more aspects to obtaining U.S.P. grade. Even the color of paint on the walls of the room (white) where the product is transferred into it's final container is a factor in obtaining this grade. Also you must register with U.S.P. and pay membership I believe, which makes you subject to an audit/inspection regarding adherence to operating standards.

Alternatively, if you produce a product that meets or exceeds U.S.P. specifications, it can be labeled as such ("meets or exceeds U.S.P. grade") without actually being U.S.P. grade.

RogueRose - 20-10-2018 at 11:09

What I have a hard time figuring out is how then do compounding pharmacies produce a lot of their custom products when I know they don't have environments as clean as the manufacturing plants.

Tsjerk: And as per the price of UPW, there are many different qualities and classifications and have different filter materials (available in various pore sizes) and obviously the smaller the pore, the slower the flow rate. Also to say it isn't that expensive is kind of misleading. A machine large enough to produce water to flow out of a lab sink is going to be pretty expensive. I haven't seen units for less than about $2,000 and some going upwards of $30-40K. Heck even a 320L storage vessel for UPW was being listed at $12k and that is basically a washing machine sized plastic container on wheels (obviously the container has to be non-leaching and is a special composition).

So some of you are saying that recrystalizations is a large part of the purification process but are there any other methods that are used?

[Edited on 10-20-2018 by RogueRose]

happyfooddance - 20-10-2018 at 11:16

The U.S.P. publishes individual standards for various different compounds. The specifications vary from compound and starting material. For example, I'm pretty sure that recrystallization is not a process step in producing U.S.P. isopropanol.

unionised - 20-10-2018 at 11:26

Quote: Originally posted by RogueRose

I'm curious about the source because it doesn't make sense and I wonder where the error lies. Have you misreported it, or are they really that badly wrong?

Re. "Are you telling me that by bubbling in HCl gas that the NaCl will "salt out"?"
Yes, I am.
You can demonstrate the effect with concentrated HCl and a saturated salt solution.

There are a number of processes used- fractional precipitation for example.
Distillation (sometimes under reduced pressure) is also common.

Not everything in the pharmacopoeia is "pure".
Opium (at least until recently) was in there- even though it's a mixture of materials made by drying poppy resin.
The requirement of the pharmacopoeia is that it doesn't have enough heavy metals to kill you and it's within 0.5% of being 10% morphine.

nimgoldman - 20-10-2018 at 14:02

The purification process very well depends on the type of compound and the impurities expected.

Iodine, for example, easily sublimates and this is the go to process for obtaining very pure iodine.

Sodium chloride can be recrystallized from brine solution, then redissolved in ultrapure water - the resulting brine is then evaporated in vacuum.

Organic compounds can be passed through a chromatographic column.

Many alkaloids can be purified by A/B extraction.

The method depends very much on the compound in question. In the USP/pharmaceutical grade, the materials used for purification are of course themselves of the appropriate grade.

Different compounds have some typical impurities in them (e.g. DMF is usually contaminated with diethylamine, acetone is usually contaminated with water etc.)

I've read a composition of pharmaceutical grade ethanol - there are many impurities allowed, such as methanol or acetone, though only in very small amounts.

Some impurities however, have to be removed completely if they show a cummulative toxicity, for example.

morganbw - 20-10-2018 at 16:00

Quote: Originally posted by RogueRose

Tsjerk: And as per the price of UPW, there are many different qualities and classifications and have different filter materials (available in various pore sizes) and obviously the smaller the pore, the slower the flow rate. Also to say it isn't that expensive is kind of misleading. A machine large enough to produce water to flow out of a lab sink is going to be pretty expensive. I haven't seen units for less than about $2,000 and some going upwards of $30-40K. Heck even a 320L storage vessel for UPW was being listed at $12k and that is basically a washing machine sized plastic container on wheels (obviously the container has to be non-leaching and is a special composition).

[Edited on 10-20-2018 by RogueRose]

Many industries have to have very pure water. Where I worked for 19 years we had a deionized water system which the conductivity was around 18 megaohm. It kicked out 100,000 gallons plus per day. Later on, another DI system was added and there was the combined capacity of around a quarter of a million gallons of highly pure water per day. This is just one example and is from the plant/industry I worked at. This is not an unusual thing to happen in industry.
It also had nothing to do with filters nor filter pore sizes.

macckone - 20-10-2018 at 20:11

There are number of grades of water.
There is distilled, multiply distilled, reverse osmosis and deionized.
Distilled and multiply distilled can have silicon dioxide or metal ions both of which are very bad for silicon chip production.
reverse osmosis can contain organics.
deionized is not supposed to contain appreciable quanities of either but is more likely to have organics.

As for salt, there are many ways to get to a certain purity.
The specifications are for the final product, not the process.

Fulmen - 22-10-2018 at 08:02

Quote: Originally posted by macckone

The specifications are for the final product, not the process.

Are you sure? IIRC there were some limitations on the process itself (back when I was a chemical analyst in a pharma-company). You can't test for every possible and impossible contaminate, any change in the process can produce unknowns.
Wasn't the Thalidomide-disaster caused by chiral products that wasn't present in the labscale production?

DavidJR - 22-10-2018 at 08:46

Quote: Originally posted by Fulmen

True, but with modern analytical instruments and well-designed methods, you can have good confidence in your ability to detect abnormal impurities etc.

Quote: Originally posted by Fulmen

Wasn't the Thalidomide-disaster caused by chiral products that wasn't present in the labscale production?

That was hypothesized, however IIRC this was never demonstrated. The real cause of the disaster was marketing a drug to pregnant women which had not been thoroughly evaluated for teratogenicity.

Fulmen - 22-10-2018 at 09:27

OK, you're probably right. I remember we did an optical rotation test on finished product. IIRC it had never given a positive result, and any such would probably cause a company-wide panic.

As for detecting the unknown it's a matter of time and cost, most tests are designed for detecting very specific components. I'm sure we had a mas spec somewhere, but most of the tests were either chemical or using HPLC with optical detectors and GC-FID. These are very robust and reliable, but there is always the risk of something slipping under the radar.
Any change in the process should require a full reevaluation of these tests, and that is a major undertaking.

They apply the same principle of caution in aeronautics. The specs for an engine part covers both the manufacture and finished product, any change will require a major re-certification.

Metacelsus - 22-10-2018 at 11:05

Quote: Originally posted by DavidJR

Quote: Originally posted by Fulmen

Wasn't the Thalidomide-disaster caused by chiral products that wasn't present in the labscale production?

That was hypothesized, however IIRC this was never demonstrated. The real cause of the disaster was marketing a drug to pregnant women which had not been thoroughly evaluated for teratogenicity.

In any case, thalidomide will racemize in vivo:

Quote:

Mean rate constants for in vivo inversion were 0.17 h−1 (R to S) and 0.12 h−1 (S to R) and for elimination 0.079 h−1 (R) and 0.24 h−1 (S), i.e., a considerably faster rate of elimination of the (−)‐(S)‐enantiomer. Putative differences in therapeutic or adverse effects between (+)‐(R)‐ and (−)‐(S)‐thalidomide would to a large extent be abolished by rapid interconversion in vivo.

So it doesn't really matter which isomer a patient consumes.

macckone - 22-10-2018 at 21:05

The USP specs are final product and do not mention the methods. (attached)
BP specs are basically the same.

BP 2013:

Sodium Chloride Cutaneous Solution

DEFINITION

Sodium Chloride Solution is a 0.9% w/v cutaneous solution of Sodium Chloride in Purified Water. The solution may be clarified by filtration.

The solution complies with the requirements stated under Liquids for Cutaneous Application and with the following requirements.

Content of sodium chloride, NaCl

0.85 to 0.95% w/v.

IDENTIFICATION

A. When introduced on a platinum wire into a flame, imparts a yellow colour to the flame.

B. Yields reaction A characteristic of chlorides, Appendix VI.

ASSAY

Titrate 20 mL with 0.1M silver nitrate VS using potassium chromate solution as indicator. Each mL of 0.1M silver nitrate VS is equivalent to 5.844 mg of NaCl.

LABELLING

When normal saline is prescribed or demanded, Sodium Chloride Solution shall be dispensed or supplied.

If the label states that the contents of the container are sterile, the solution complies with the following additional requirements.

Sterility

Complies with the test for sterility, Appendix XVI A.

Attachment: Sodium Chloride Injection .pdf (42kB)
This file has been downloaded 362 times

macckone - 22-10-2018 at 21:12

Attached is the NF sodium chloride monograph used to make the USP solution above.
No mention of methods.

Attachment: Sodium Chloride .pdf (54kB)
This file has been downloaded 312 times

unionised - 23-10-2018 at 11:11

Quote: Originally posted by macckone

The USP specs are final product and do not mention the methods. (attached)
BP specs are basically the same.

BP 2013:

Sodium Chloride Cutaneous Solution

DEFINITION

....

Sterility

Complies with the test for sterility, Appendix XVI A.

Appendix VI tells you the method you use to test for chlorides

Appendix XVI A defines the method you must employ to test for sterility.

And so on.
The methods certainly are specified.

Quote: Originally posted by macckone

Attached is the NF sodium chloride monograph used to make the USP solution above.
No mention of methods.

This
" Dissolve about 3 mg of Sodium Chloride in 2 mL of water. Acidify with diluted nitric acid
and add 0.4 mL of silver nitrate TS. Shake, and allow to stand. A curdled, white precipitate is
formed. Centrifuge, wash the precipitate with three 1-mL portions of water, and discard the
washings. Carry out this operation rapidly in subdued light, disregarding the fact that the
supernatant may not become perfectly clear. Suspend the precipitate in 2 mL of water and add 1.5
mL of 10 N ammonium hydroxide. The precipitate dissolves easily with the possible exception of a
few large particles, which dissolve more slowly.
"
is a method.

[Edited on 23-10-18 by unionised]

macckone - 23-10-2018 at 19:28

The methods for manufacture. Not the test methods.

These are tests not manufacturing instructions.
You are free to use any manufacturing methods provided they meet the specs and don't introduce dangerous impurities.

The beginning section says that
"Official substances are to be prepared according to recognized principles of good manufacturing and from ingredients complying with the specifications designed to ensure that the resultant substances meet the requirements of the compendial monographs (see also Foreign Substances and Impurities under Tests and Assays)."

It also says "There may be deviation from the specified processes or methods of compounding though not from the ingredients or proportions thereof, provided the finished preparation conforms to the relevant standards laid down herein and to preparations produce by following the specified process"

It is literally saying you don't have to follow a specific process to manufacture it. But the process does have to be sound and the product has to meet the specifications including no foreign substances can be present.

unionised - 24-10-2018 at 13:02

Fair point; they don't care where you get the material from, as long as it passes the tests.

Things like GMP and GLP do that.

[Edited on 24-10-18 by unionised]

brubei - 25-10-2018 at 00:29

Industrial standards only watch on quality through many standardized measurement methods.

Process of production can then evolve in many way to improve sustainability, cost or safety, without rewriting all standards with new innovation (and there are plenty of innovation all time). Innovation has a cost and need invest, by this way this cost is only supported by the industrial who claim to "change the world" and standard revision occurs by other actors (politics or else) with theoretical no conflict of interest.