The Thermo Fisher Ion Chromatography (IC) is an efficient analytical instrument based on ion exchange technology, mainly used for separating and detecting anions, cations, and polar organic compounds in solutions. The core principle is to achieve ion separation through the interaction between the fixed phase and the mobile phase, combined with a high-sensitivity detector to complete quantitative analysis.

1. Separation mechanism: The separation of ion chromatography mainly relies on the ion exchange interaction between the stationary phase (ion exchange resin) and the mobile phase (eluent). Separable ions on the stationary phase undergo reversible exchange with ions with the same charge in the sample. Due to the varying affinities of different ions towards the resin, ions with weaker affinities are preferentially carried away by the eluent, while ions with stronger affinities remain for a longer period of time, thus achieving separation.

2. Suppression system: In order to reduce background conductivity and improve detection sensitivity, the suppressor generates H2 and OH2 by electrolyzing water, neutralizes strong electrolytes (such as sodium carbonate/sodium bicarbonate) in the rinse solution, and converts them into low conductivity carbonic acid or water, thereby highlighting the electrical signal of the tested ion.

3. Testing method

-Direct conductivity detection method: Non inhibitory system directly measures the conductivity value of separated ions, suitable for simple sample analysis.

-UV absorption spectrophotometry: based on the absorbance of target ions at specific wavelengths for detection, suitable for ions with UV absorption characteristics.

-Post column derivatization photometry: The target ion is converted into a colored compound through derivatization reaction for detection, commonly used for the analysis of specific ions in complex matrices.

Precautions for using Thermo Fisher ion chromatograph:

-Environmental requirements: Ensure that the laboratory temperature is stable within the range of 15-30 ℃, the relative humidity is controlled between 30-80, and at the same time, ensure good ventilation around the instrument and no strong electromagnetic interference sources.

-Power supply inspection: Confirm that the power supply voltage is stable (220V ± 10), check that the grounding wire connection is reliable, and it is recommended to equip an uninterruptible power supply (UPS).

-Consumable preparation: Prepare sufficient ultrapure water (resistivity ≥ 18.2M Ω· cm).

-Daily maintenance: Regularly clean and maintain the instrument, including replacing pump oil, cleaning pipelines, checking seals, etc., to ensure the normal operation of the instrument.

-Safe operation: Follow laboratory safety regulations and wear appropriate personal protective equipment such as gloves, goggles, etc.