Inverse chromatography analyzes organic acids in grains.

Overview
Generally speaking, inverse, ion exchange/size blocking
chromatography
methods are commonly used in
organic
acid analysis in grains.
inverse chromatography, ODS columns are commonly used to inhibit ion interaction between organic acids and fixed phases using acidic seculption. Despite this debasing condition, abnormal peaks often occur on chromatography when the actual sample is injected directly into the
-chromatography column
. We investigated the abnormality of organic acid peaks in the TOSOH IC-2010 ion chromatography system. This paper discusses the effect of chromatography conditions on improving organic acid peaks in different actual samples.
experiments
column
analysis column: TSKgel ODS-100V, 3um, 4.6mmID x 15cm
pre-pillar: TSKgel SCX, 5um, H type, 4.6mmID x 2cm
analysis column produced by Japan Tosoh, pre-pillar by homemade Tosoh domestic.
Instruments
Instruments: Ion Chromatography IC-2010 (Tosoh, Japan), UV-8320IC (Tosoh)
Data Processing: Ion Chromatography Workstation (Tosoh)
Chemicals and

reagents
water in cleansing conditions, as well as sample preparation, are prepared using the Milli-Q water purification system (Miribo, Japan)
insulated solvents and organic acids
sysm standard

Enhanced resins are made from TSKgel-suppressed IC-A cation exchange resin (Tosoh)
1: Abnormal peak shape of organic acid on ODS columns
sample 1: salicy acid (250mg/l) 2: Methanol (500mg/l) 3: appleic acid (500mg/l) 4: Lactic acid (500mg/l) 5: acetic acid (250mg/l) 6: citric acid (250mg/l)7: butyric acid (250mg/l) 8: antibutyl acid (250mg/l) 9: acrylic (1000mg/l) 10: butyric acid (250mg/l)
conditions Column: TSKgel ODS-100V 3um, 4.6mmID x 15cm
Excerpt: 0.1% H3PO4 Sample Solvent: Water
Flow Rate: 1.2 0ml/min Temperature: 40C
Sample: 30ul Detector: UV210nm
Instrument: IC-2010 and UV-8320IC
2: Sample concentration to peak type Effect
3: Suppressing Overload
4: Improving Peak Type, Improving Selective
5: Actual Sample
Summary
1: When analyzing organic acids, it is easier to show overload trends using ODS inverse columns than other chromatography methods.
2: The preparation of samples using acidic solvents can effectively suppress overload, and the balance between organic acids in sample solution and dissoquents in fixed phases can be controlled to more standard hydrophobic effects.
3: The use of H-type cation exchange resin as a pre-pillar can also effectively suppress overload.
4: Using SCX resin as a pre-pillar does not reduce the separation performance of ODS columns.
5: In addition, organic acids with high Pka values can be used with potassium-type cation exchange resins before samples are detected, making conductivity and selectivity higher.
6: The method provided in this paper can be applied to the detection of organic acids in grain.
.