Buffers cautions when using

C should be used with caution when operating at intermediate or high pH values with phosphate buffers. Operation at pH < 3 and elevated temperature can degrade the bonded stationary phase more rapidly and cause retention reproducibility instabilities. However, there are specially end-capped columns available commercially that can withstand higher temperatures with significantly less hydrolysis. 

Remove bucket from microwave and allow sections to stand for a further 10 min in the hot buffer. Use extreme caution when removing lid from bucket of hot buffer always wear gloves because steam and buffer are very hot. 

Buffers are often added to control pH, but caution must be exercised when buffers are used in a formulation to be freeze dried. As discussed earlier, crystallization of either buffer component (acid or base) during freezing may cause a significant pH shift during freezing, thereby causing greater pH variation than would have been obtained in an unbuffered system. 

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