Anion Standards (15) (Comparison of NI-424 and I-524A)

The seven main anions can be separated using a newly developed column, IC NI-424 quickly. The theoretical plate number of the column is more than double that of the existing column IC I-524A.
Comparison with I-524A column:
1) NI-424 column has achieved separation of phosphoric acid ion and fluoride ion which was difficult to sepatate using I-524A.
2) With NI-424, each peak is sharper, and separation of ions and peak balance have been improved. In particular, improvement has been made in the separation of chloride and nitrite ions making NI-424 column suited to the analysis of a trace amount of nitrite ion contained in high-concentration chloride ion; demand for such analysis is high in the area of environmental analysis.


Sample : 20micro-L
1. H₂PO₄^- 10mg/L
2. F^- 1mg/L
3. Cl^- 1mg/L
4. NO₂^- 5mg/L
5. Br^- 5mg/L
6. NO₃^- 5mg/L
7. SO₄^2- 5mg/L

(Left)
Column       : Shodex IC I-524A (4.6mmID*100mm)
Eluent       : 2.5mM Phthalic acid + 2.3mM Tris(hydroxymethyl)aminomethane aq.
Flow rate    : 1.2mL/min
Detector     : Non-suppressed coductivity
Column temp. : 40deg-C

(Right)
Column       : Shodex IC NI-424 (4.6mmID*100mm)
Eluent       : 8mM 4-Hydroxybenzoic acid + 2.8mM Bis-Tris + 2mM Phenylboronic acid + 0.005mM *CyDTA aq.
Flow rate    : 1.0mL/min
Detector     : Non-suppressed coductivity
Column temp. : 40deg-C

^* CyDTA: trans-1,2-Diaminocyclohexane-N,N,N',N'-tetraacetic acid