Determination of Amoxicillin with Novel Rhodanine Ramification by Flow Injection Chemiluminescence

3-(4'-fluorophenyl)-5-(2'-sulfonylphenylazo)-rhodanine (4FRASP) firstly synthesized by the authors was used as chemiluminescence (CL) reagent. In acidic medium, CL was observed when amoxicillin was injected into the mixture of 4FRASP-potassium permanganate. Based on this phenomenon, a flow injection CL method was established for the determination of amoxicillin. The CL intensity was correlated linear with the concentration of amoxicillin over the range of 5.0times10
^-8
to 2.0times10
^-5
g-mL
^-1
and the detection limit was 4.5times10
^-9
g-mL
^-1
. The relative standard deviation (RSD) was 1.3 % for determination of 1.0times10
^-6
g-mL
^-1
amoxicillin (n=11). This method was applied to the determination of amoxicillin in amoxicillin capsules successfully.