The Instructions of C18 SPE Cartridge
HAWACH SPE cartridges are available in 1ml, 3ml, 6ml and12ml and the packing materials include four major types: silicone bonded matrix, polymer matrix, adsorption matrix and special column. The silicone bonded matrix includes reversed phase C18, C18-ne, C8; normal phase Silica, Diol, CN; ion exchange SAX, SCX, NH2, PRS, PSA; mixed mode C8/SCX, C8/SAX. The polymer matrix includes HLB, MCX (PS/DCB), MAX (PS/DCB), WCX (PS/DCB), and WAX (PS/DCB). The Adsorption matrix contains alumina (AI203), graphitized carbon black (GCB), and Florisil pesticide residue. As for the special column, it is for azo dye detection column, etc.
Usage of C18 SPE cartridge
Sample processing is the most common step in the analysis. C18 SPE cartridge is a sample-processing solid phase extraction device that is easy to use and recyclable. The C18 SPE cartridge reduces sample processing time and can be used as follows:
Purification: The packing in the SPE cartridge adsorbs the compound of interest or impurities in the sample. Thus, when the sample flows out, the selected compound (including impurities) is left on the extraction column.
Micro extraction or concentration: The analyte can be concentrated when the amount of analyte is below the method limit.
Separation: Gradient elution based on different polarities of the sample, extraction of samples, and increase of sample concentration.
Dissolution exchange: Dissolution exchange: If the sample is poorly soluble, the analyte can be adsorbed and eluted through the cartridge with a suitable solvent.
The following are the five steps when using C18 cartridge, each of which is different but not required.
Step 1: Prepare the sample-The sample can be either liquid or air phase. If it is a solid phase, the sample must be decomposed or extracted before the column.
Step 2: Activation or equilibration of the column– For reversed phase columns such as C18, activation is necessary. The strong column is used to wet the column stationary phase, and then the weak column is used to equilibrate and activate the column.
Step 3: Load– Load the sample into the extraction column. At this point, the packing in the solid phase extraction cartridge will adsorb the compound of interest or the impurities in the sample. Thus, when the sample flows out, the selected compound (including impurities) is left on the extraction column.
Step 4: Flushing–The impurities are rinsed with a rinse that is strong enough to elute the impurities and is weak enough to retain the compound of interest.
Step 5: Eluting the compound of interest–Use a solvent to elute the compound adsorbed on the extraction column in the solution.
Factors affecting separation
The sample separation effect is related to the flow rate and upload. Here are suggestions:
Flow rate of C18 – if the sample flow rate is too fast, the active ingredient may not remain in the adsorbent, so the flow rate is 5 to 10 ml minutes when the column is activated.When loading and eluting samples with other ion exchange columns, the flow rate of the crucible is 0.2~1ml minutes, and the flow rate of other small columns is 2~10ml minutes.
Sample Loading – The loading of the cartridge depends on sample structure, solution volume, solvent polarity, adsorbent type and amount, and sample adsorption performance.
Storage of C18
The small column can be stored in a sealed plastic bag for a long time. If the unused column is placed in an open plastic bag, the air in the bag should be drained, the bag mouth should be tightened twice, and sealed with a sealing tape. Store it in a desiccator.