How to Solve Solid Phase Extraction Cartridge Common Problems?

Regarding the common problems in the use of extraction columns, there are generally low recovery rates, poor reproducibility, poor purification effects, and flow rates that are too fast or too slow. HAWACH has summarized the possible reasons and solutions for your reference. Also, you are welcome to contact us for further discussion.

  1. Low recovery rate

Cause Analysis:

a. Insufficient retention of the target on the packing

Possible CausesSolution
SPE column selection is inappropriateChoose a stronger retention SPE column
The elution strength of the sample loading solution or eluent is too strongReduce the elution intensity of the sample loading solution or eluent
Overload caused by too high sample volume/concentrationIncrease the amount of filler or reduce sample volume/concentration
During the operation, the small column “dries up”Reactivate/equilibrate to ensure that the cartridge does not “dry up” before the end of the elution

b. Incomplete target elution

Possible CausesSolution
Small column retention is too strongChoose a slightly weaker SPE column
The elution capacity is too strongEnhanced elution intensity
The elution volume is too smallEnhanced elution volume

c. Other reasons

Possible CausesSolution
Insufficient extraction of pre-processingChange the extraction solvent
Unstable, volatilized, or decomposed target substanceReduce heating temperature, change the extraction and transfer mode, and add buffer salt to adjust the pH of the compound which is greatly affected by pH
Complex pretreatment processSimplify the pretreatment process
Combination of target and impuritiesChange the appropriate method to remove impurities
The impurity interference effect is too strongChange the pre-processing method or compare it with the matrix spike material
Too much impurity, exceeding the maximum retention of the small columnChange the pretreatment method, reduce the amount of sample loading or increase the amount of small column packing
  1. Reasons and solutions for poor reproducibility
Possible CausesSolution
The operation steps are cumbersome and caused by human errorChange the pre-processing method or formulate SOP method
Poor impurity removal effect for complex sample matrixChange the whole pre-processing method, add internal standard or compare with matrix spiked data
Dry up during sample loadingReactivate balance
Column clogging occurs or the flow rate is too fastThe former changes the pretreatment method, the latter uses a check valve to control the flow rate
  1. Solutions for poor purification effect

a. Change the pretreatment method

b. Change the intensity of eluent and eluent

c. Choose the appropriate role column

d. Carry out SPE operation correctly

  1. Reasons and solutions for too fast or too slow flow rate
Reason for the slow flow rateSolution
SPE selected particle size is too smallChoose large particle size SPE
The suspended insoluble matter remains after sample pretreatmentFreeze centrifugation before loading
Sample viscosity is too highSample dilution
SPE resistance is too large, and the liquid cannot drop by gravityUse a manual solid phase extraction column device to adjust the flow rate by adjusting the check valve, the valve, and the negative pressure
Reasons for too fast flow rateCountermeasure
SPE selected particle size is too largeChoose a small particle size SPE
The flow velocity is still very fast under the action of gravityUse a manual SPE device to adjust the check valve
The flow rate is too fast when pumping negative pressureAdjust the check valve and valve to control the pressure of the vacuum gauge to be constant within a certain range