8/22/2014
13
CPC Titration
–
CPC cation forms ion pair with large CS anion
–
Ion pair has poor solubility and causes turbidity
A t f t bidit i
ti
l t
t
–
moun o ur
y s propor ona o amoun
of CS in solution and can be measure with
optical sensor (phototrode)
–
Non‐Specific
•
Will react with any large polyanion
•
Small additions of hexametaphosphate will increase
results dramatically
•
Can not be used as stand‐alone method; must be
used in conjunction with appropriate identity and
purity tests.
Outcome of WG Meeting on 3/21/14
•
Proposed Fitness for Purpose Statements
1. Assay Method: Accurately quantify total CS in raw
materials & finished products as a neat substance
and in the presence of other ingredients
2. Identity Method (1): Accurately identify CS in raw
materials & finished products and distinguish CS
from economic adulterants
3. Identity Method (2): Accurately identify the
source of CS in raw materials
4. Purity Method: Detect known adulterants in CS in
raw materials & finished products at a specified
level and confidence
