I work in a small rural lab that does minimal BB each month. Our 10L box of saline from Cardinal indicates it should be used within one month, so we are discarding about 9L of saline each month. The smaller containers are more expensive, so.. can saline be validated for use for longer than the manufacturer recommends? We also use this saline for micro testing. Can showing no growth and negative Coombs reactivity each month be considered validation? Any help is appreciated!

22 minutes ago, kblewett said:

I work in a small rural lab that does minimal BB each month. Our 10L box of saline from Cardinal indicates it should be used within one month, so we are discarding about 9L of saline each month. The smaller containers are more expensive, so.. can saline be validated for use for longer than the manufacturer recommends? We also use this saline for micro testing. Can showing no growth and negative Coombs reactivity each month be considered validation? Any help is appreciated!

Hi kblewett, Happy New Year. While I am no expert I would say, from a practical perspective, that I can not see how throwing away 90% of a perishable product, of the larger volume size, would be less expensive then buying less of the smaller volume size of the same product at higher cost initially but would allow for use of greater volume of the bottle, once opened, and sustain a longer shelf life, with the exception of unexpected storage environmental mishap, enabling you to absorb the higher cost.  In other words, buy less quantity of the smaller volume size at an initial higher cost, but be able to use near 100% of the volume and because it is the smaller size you would be able to store it, unopened, for a longer period. These to benefits may help absorb some, or all, of the higher cost.

I hope this helps some.

 

1 hour ago, kblewett said:

I work in a small rural lab that does minimal BB each month. Our 10L box of saline from Cardinal indicates it should be used within one month, so we are discarding about 9L of saline each month. The smaller containers are more expensive, so.. can saline be validated for use for longer than the manufacturer recommends? We also use this saline for micro testing. Can showing no growth and negative Coombs reactivity each month be considered validation? Any help is appreciated!

While it is not impossible, it can be extremely ticklish to extend an expiration date (of anything) beyond that of the manufacturer. You may find that the burden of proof required exceeds the value of the theoretical savings. You also have to remember that the manufacturers of the products put on that expiration date for a valid reason - presumably their testing indicated some deterioration/deficiency over time.

Certainly microbial contamination is an issue and culturing may provide useful data. However, and this is a BIG HOWEVER, most BB saline products do not contain preservatives and don't claim sterility after opening. Therefore, you will undoubtedly end up at some point with positive cultures on opened containers. The question then becomes "How much contamination can our test system tolerate ?" - a very difficult question to answer satisfactorily.

Perhaps more importantly for BB testing is stable pH and any plan to extend the expiration date of saline should include pH testing.

I appreciate both of your replies. I am in a fun position, where I have come into this lab with experience from larger ones, and have noticed a looser interpretation of guidelines and more blowback when suggesting changes. It's nice to have a leg to stand on when people ask me why I'm suggesting such changes. 

I personally prefer the idea of just using smaller containers, so I will prepare for the battle of explaining why more expensive (initially) is better. Thanks again!

Just a little free advice and it's worth every penny.  Pick your battles carefully and make sure they are worth fighting and the potential cost of losing.  Good luck.

Hello - We went to the smaller containers years ago because the large ones were too heavy to comfortably lift and move.  It is worth the extra cost to save a tech's back/neck/shoulders!

41 minutes ago, bldbnkr said:

Hello - We went to the smaller containers years ago because the large ones were too heavy to comfortably lift and move.  It is worth the extra cost to save a tech's back/neck/shoulders!

Perfect ! Throw in a risk of workers' comp. and the argument is won quickly. Nicely played.

No, you can't validate anything to last longer than what the manufacturer states when it comes to stability of use. It would be considered using "expired" reagents by regulators and a citation could be written as such. I throw a lot of saline away as well, but it's better than worrying about getting cited for using expired reagents.

You might try a different vendor for saline.  Surprisingly, many of them have different expirations.

You might try doing a colony count on your saline as it reaches expiration date.  We found >100,000.  Discard it.