2 Main Aspects to be Considered for Choice of SPE Cartridge
2 Main Aspects to be Considered for the Choice of SPE Cartridge
SPE and SPE cartridge Developed on the basis of traditional liquid-liquid extraction, the solid phase extraction(SPE)’s working principle is based on similar mutual solubility and similar interaction between substances, and in combination with the widely used basic knowledge of liquid chromatography and gas chromatography stationary phase. The solid phase extraction device is a widely used and popular sample pretreatment technology that uses solid adsorbents to adsorb target compounds in liquid samples, separate them from the matrix and interfering compounds of the sample, and then reuse them. The eluent is eluted or heated to desorb to achieve the purpose of separating and enriching the target compound.
Any part of the SPE cartridge that can be in contact with the sample will contaminate the end sample if impurities dissolve out. Therefore, the material of each part has an explanation for HAWACH SPE cartridge, namely: SPE is composed of medical PP empty tube, medical PE sieve, fixed adsorbent (also called stationary phase). HAWACH SPE cartridge have the characteristics of strong corrosion resistance and low impurity content, so the impurity dissolution probability is low and has an excellent purification function. The solid phase extraction cartridge is a widely used and increasingly popular sample pretreatment tool. It has been widely used in food, environment, pharmaceutical, and other industries and has become one of the effective means of sample pretreatment and purification. SPE cartridge mostly uses gravity to flow down by itself or it is combined with SPE device to accelerate the separation speed by vacuuming. Today, we will discuss how to choose the cartridge and how to use it.
2 main aspects to be considered for the choice of SPE cartridge Different kinds of SPE cartridges are available. We need to consider the detection methods, analytical object, and laboratory conditions to choose the suitable packing and reasonable specifications in actual experiments. In general, two aspects need to be considered when choosing the solid phase extraction cartridge: the choice of adsorbent and cartridge specifications.
Adsorbent 1. The adsorbent can be selected mainly according to the properties of the target compound and the properties of the matrix. Appropriate adsorption packing can make the interfering substance and the target component get good separation and meet the recovery requirements. But, the compound quality which can absorb the adsorbent is limited. Overload will occur if there is too large sample volume and makes the target without being retained penetrate the extraction cartridge. The choice of adsorbent can be roughly selected by the above two methods.
cartridge specifications 2. In addition to the appropriate adsorbent, selecting the appropriate cartridge specifications is also important based on the sample volume required for the verification. Because the adsorbent of the extraction cartridge can adsorb the quality of the compound is limited, once this value is exceeded, the target substance cannot be effectively retained, which greatly reduces the elution effect. Therefore, it is necessary to select the appropriate cartridge specifications according to the number of components in the sample.
The adsorption capacity of the SPE cartridge packing is what we called the capacity. Generally, the silica-based SPE cartridge’s capacity is 1~5 mg/100 mg, equals to mass packing’s 1%~5%. The capacity of the bonded silica gel ion exchange adsorbent filler is expressed in meq/g, that is, the capacity of each gram of filler is X milliequivalents. Generally, this kind of filler’s capacity is 0.5 to 1.5 meq/g.