Bonded silica sorbents are commonly used for the solid phase extraction of analytes from complex sample matrices. Functional groups, such as octyl (C8) and octadecyl (C18), can be bonded to the silica surface to provide non polar interactions. Each of these sorbents exhibits unique properties of retention and selectivity for a particular analyte. The choice of which sorbent is best for a particular method will be influenced by the percent recovery of analyte from the sample matrix and the cleanliness of the resulting chromatography.
| Bonded Functional Group |
Octadecyl |
Octyl |
| Retention Mechanism |
Strongly non polar |
Moderately non polar |
| Endcapped |
Yes |
Yes |
| Percent Carbon (avg.) |
18% |
12% |
| Pore Size (avg.) |
60 Å |
60 Å |
| Applications: |
- Opiates
- THC
- Antibiotics
- Bronchodilators
- Pesticides
- Hypnotics
- Antiarrhythmic
- Vasodilators
|
- Antidepressants
- Benzodiazepines
- Corticosteroids
- Anticonvulsants
- Peptides
- Antihypertensives
- Analgesics
- Immunomodulators
|
|
|
| Chemical Structure |
 |
|
Product Usage
The versatile Empore™ C8 and C18 products allow for use in the following applications:
- The small bed volume and sorbent mass within Empore™ Extraction Disk Cartridges and 96-Well Solid Phase Extraction Plates allow for the use of reduced solvent volumes and result in more concentrated eluates.
- In HPLC methods, the ability to direct inject is now possible when the eluate is compatible with mobile phase.
- Time-consuming evaporation and reconstitution steps may be eliminated.
- Recoveries may be improved by avoiding analyte thermal instability problems associated with an evaporation step.
