Excipient Absorbance background

IMPORTANCE OF EXCIPIENT ABSORBANCE BACKGROUND TO LOW-DOSE IMPURITY ANALYSIS... 

Excipient Absorbance Background in Impurity Analysis for Typical Dosage Formulation... 

As demonstrated above, tackling the excipient absorbance background problem is challenging in low-dose analytical development. Though approaches may be different, it is clear that none of the solutions come easily. They come at the expense of longer development times and more intensive manpower. Therefore, the question facing a development scientist is whether there are more effective approaches to low-dose analytical development that deal with the excipient absorbance background issue. The answer is yes ... 

The absorbance at 280 nm is convenient for monitoring protein concentration because it is broad, relatively insensitive to protein conformation and not overly prone to background interference. In contrast, the protein backbone absorbs strongly in the far-UV region (below 240 nm), but these absorbance bands are highly dependent on protein conformation and very susceptible to backgrovmd interference (many molecules, such as salts and common buffer excipients, absorb significantly in the far-UV). Use of the absorbance method assumes that the... 

---