Hi everyone...

Over the past few months, I have been developing and validating HPLC methods for sunscreen actives (raw materials). Now it has reached the time to work on finished products, to develop and eventually validate methods for the assay analysis of sunscreens. There is somewhat of a debate as to the extent of method validation that will need to be performed.

My company manufacturers several different products containing sunscreen actives, ranging from oils to lotions to lip balms,etc. One opinion is to develop a method that applies to a particular "family" (ie lotions) then validate that method, and then subsequently do the same for the other families like balms, etc.

The other opinion is that I would need to develop and validate a method for every single formula we have on hand (which exceeds well over 100) that has a sunscreen active ingredient. The reasoning is that even though I may have validated a method for a particular sunscreen product like a lotion how can we show proof that the method is not affected by other excipients in another similar lotion formula?

So in a round about way, my question is...to remain thoroughly compliant, is it necessary to develop and validate a method for every single formula, or is it acceptable to develop and validate methods based upon a particular "family" of product? If so, what would be the scientific justification for doing so? Obviously the latter is a more economical and less time consuming procedure, but I don't want any problems later on down the line. Any advice?

Hello,

We also developed a method to quantitate the UV-filters in all kind of products. With this method we can quantitate 16 UV-filters. The validation was performed for 12 components. Because there are a lot of matrices in cosmetics, we validated the method for three matrices, spray (oil base), a W/O-emulsion and a O/W-emulsion. To us this is the best we can do. Otherwise you should validate for all kind of matrices (O/W/O-emulsions, W/O/W-emulsion etc.) This would be a hell of a job. When I look at the results for each filter they are for each matrix comparable.

Good luck.

We had purchased a company which had a few sunscreen products but it never had bothered to assay the sunscreens or develop/validated test methods. My company had test methods but from before "compliance" days but since we had not had an actual product with those actives, we had to validate the method. Of course sunscreens are usually easy, in products at high levels and UV absorbances at wavelengths that usually render the matrix transparent. We showed limit of detection and quantitation to be pretty irrelevant in this situation, and didn't spend too much time on those, just included a point of view. I agree, you'll spend a lifetime trying to validate each matrix. As it was, we did the multiple operators, columns, HPLC units, etc., even though ours are all computerized so the only real differences were weighing and diluting to volume. Our other OTC products: for a new but somewhat similar matrix, we just show applicability, run a placebo product, etc.

To durk...

Thanks for the info. Has your company been audited by the FDA at all? If so, were the methods that you developed and the corresponding validations considered acceptable by FDA standards? I agree and would think that would be the best (and most time efficient) way for method development by grouping them, but I didn't want to get caught up in any "technicalities" later on down the line. Do you think this is where I could make assumptions that within a given sunscreen class (like an oil) that even though there are variations from one formula to another that the inactive excipients are assumed to behave the same way, therefore justifying using one method for one particular class? Thanks so much!

Hello,

Our company is not audited by the FDA. In our country this is done by another organisation comparable to the FDA. We have to comply with NEN-ISO 17025.

Of course there are many different sunscreen classes, but it is all depending your method if you make some assumptions. In the method it is important you break each emulsion type. We analyzed about 400 different samples and we think all UV filters were extracted from the matrix. We also analyzed a reference material and the results were satisfying.

Durk

Hi

IŽve just started to work with cosmetics and I donŽt know how to start to create methods and validate them,by HPLC
So, can you give me any clue to start by

B

Hi Beatriz,

It's depending what components you are looking for. I suggest you start a literature search for those components you want to investigate.

Durk

Hi Durk

I have been looking for methods for a while and I found good conditions to analize glicolic acid in creams,for example.
But I dont know the steps to create the method and validate it
I have been doing quality testing for a pharmaceutical company and all the methods were created and validated by somebody else, so for me it was routine tests.
This is the reason why I am so lost, this is completely new for me and I am on my own working on it, nobody here knows anything about HPLC

Thanks
B

Hi B,

If you have a method and you have the chemicals and a HPLC, what is the problem performing the analysis?

Durk

Hi Durk

I just have the conditions, but I dont know the steps to create and validate a method
For example, shall I do a std curve every time I perform an analysis? or if I really have a good one it is enough to have one to validate the method.
Maybe it is obvius, but I am a beginer!

Thanks for your time
B

Hi B,

Every time we do an analysis we create a calibration curve by injection of 5 standards of different concentrations (p.e. 20-100 ppm). How to validate your method is depending your quality system. We work with NEN-ISO-17025. You have to analyze the limit of detection and quantitation, the recovery at different levels etc.

Durk

Hi Durk,

Thank you very much for your tips, you are a big help, so I am going to start with it!
If you are around IŽll probably ask you again(if you donŽt mind)
We work with ISO 9001, so weŽll have some variations to validate it!

B

Beatriz -

If you want to learn the steps by which you can develop and validate an HPLC method, a good start would be to obtain a copy of Snyder's Practical HPLC Method Development. Also, I think it would be a wise move to calibrate your instrument each time you set up an assay. Running a system suitability and having your calibration standards evenly interspersed throughout your run works well, too. Those three things will go a long way toward assuring the quality of your data. Also, keep your LC's in top shape and they'll deliver good data almost indefinitely.

I've done a fair amount of work with sunscreens in cosmetics as well. Feel free to email me off the forum if you need any specific information.

One thing to ALWAYS be conscious of with these kinds of samples is recovery. The matrices are often complex and sometimes getting full recovery of all analytes can be tricky. What works wonderfully for one sample may not work well at all for another sample that appears otherwise to be very similar. Sample prep is crucial.

Cood luck!

Chris

Chris

Thank you very much!!!
IŽll have a look at SnyderŽs book and IŽll email you if I need more information.

Beatriz

Beatriz,

I was in the same boat. I had a lab built from scratch with no established methods...nothing. I am the only one in the entire company that has any kind of experience with HPLC...and it was even limited when I started. I'm not sure what country you're regulated by...by I used the USP, CDER, FDA and ICH guidelines to structure what I needed to perform a method validation.

My first validation was somewhat tricky, because I wanted to make sure I was doing it right. After the first one...you will get the hang of it in terms of data handling, etc. and before you know it you'll be considered a method validation coordinator like I am now!

Hi anonymous

Thank you, I feel better now,IŽll be alright, it is difficult at the beggining and then IŽll start to know how everything works, even in each country is different, so probably here in Spain it doesnŽt work as it does in your country.

Beatriz

Does anyone kjnow where I could get info. on Topical Sunscreen Validation. I am doing a research and would like to know where I could go to obtain info. Thank You