Choosing the right Solid-Phase Extraction (SPE) column shouldn't feel like solving a complex chemistry puzzle. Yet with dozens of options—C18, Florisil, NH2, HLB, GCB—this critical decision can overwhelm even experienced lab professionals. The truth is: your SPE column choice directly determines your analytical success.
The First Step Is To Pinpoint The Four Key Questions：
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Polarity：
Non-polar,moderately polar,or highly polar?
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Ionization State：
Acidic, basic, or neutral at your sample pH?
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Functional Groups：
What chemical moieties are present?
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Aqueous：
Environmental water，buffers，biological fluids
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Organic：
Food extracts，soil/sediment eluents，organic solvents
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Biological：
Plasma，serum，urine，tissue homegenates
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Cleanup：
Remove interfering compound（proteins，pigments，lipids）
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Concentration：
Enrich trace analysis from large volumes
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Desalting：
Remove salts for downstream MS analysis
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Class Separation：
Isolate specific compound groups
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LC-MS/MS：
Requires ultra-clean extracts，minimal column bleed
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GC-MS：
Needs solvent compatibility and volatility considerations
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HPLC-UV/Vis:
Tolerates slightly more matrix interference
The SPE Column Selection Matrix: Match Mechanism to Your Needs
Use this interactive guide to quickly identify the optimal SPE chemistry for your application
| SPE Column Type | Best For These Analytes... | And These Matrices... | Key Mechanism & Special Advantages |
|---|---|---|---|
|
Reversed-Phase
(C18, C8, C4)
|
Non-polar to moderate polarity compounds PAHs Pesticides Pharmaceuticals |
Aqueous samples Water Buffers Biological fluids |
|
|
NH2
(Aminopropyl)
|
Carbohydrates, organic acids, anions Sugars Organic acids Glycols |
Various Food extracts Plant materials Beverages |
|
|
HLB
(Hydrophilic-Lipophilic Balance)
|
Broad spectrum: acidic, basic, neutral Multi-class compounds Pharmaceuticals Contaminants |
Complex matrices Environmental water Biological fluids Food extracts |
|
|
GCB
(Graphitized Carbon Black)
|
Highly polar compounds, pigments Pigments Chlorophyll Humic acids |
Colored extracts Plant extracts Vegetables/Fruits Environmental samples |
|
|
Florisil
(Magnesium Silicate)
|
Polar compounds, pesticides Lipids Pigments Pesticides |
Organic solvents Hexane DCM Ethyl acetate |
|
The 5 Most Common SPE Selection Mistakes (And How to Avoid Them)
❌ Mistake 1: Using C18 for Everything
Example: Trying to extract polar carbohydrates on C18
Solution: Consider NH2 for sugars, HLB for broad-spectrum applications
❌ Mistake 2: Not Using GCB for Pigmented Samples
Example:* Green vegetable extracts clouding HPLC columns
Solution:* Add GCB cleanup step for chlorophyll removal
❌ Mistake 3: Ignoring HLB's Method Development Advantages
Example: Spending weeks optimizing C18 for mixed-polarity compounds
Solution:* Start method development with HLB for its wider polarity coverage
❌ Mistake 4: Overlooking Column Dry-Out Issues
Example: Failed extraction after vacuum manifold ran too long
Solution:* Use HLB columns if dryness is a concern in your workflow
❌ Mistake 5: Single-Column Mindset for Complex Samples
Example: Poor recovery due to matrix effects
Solution:* Consider tandem SPE (e.g., C18 followed by GCB or NH2)
艳 李
