- Conventional HPLC column built to be the cornerstone for your lab; pressure rated for any 400 bar HPLC system.
- Solid and reliable—delivers the peak shape, reproducibility, ruggedness, and performance you demand.
- Exceptional value for routine analyses and large-volume workflows—high-purity, fully porous silica backed by quality manufacturing features a variety of phases to fit most HPLC methods.
- Ideal for a wide range of applications from food to pharma; 5 phases cover 98% of USP methods.
- Newly designed minimal packaging for compact storage—download serial #-specific certificates of analysis at restek.com/documentation
Roc Family of HPLC Phases
C18 | C8 | Phenyl-Hexyl | Cyano | Silica | |
| USP Phase Code | L1 | L7 | L11 | L10 | L3 |
| Stationary Phase Category | C18, octadecylsilane | C8, octylsilane | phenyl | cyano | bare silica |
| Ligand Type | monomeric C18 | monomeric C8 | phenyl-hexyl | cyanopropyl | n/a |
| Particle Size | 3 μm or 5 μm, spherical | 3 μm or 5 μm, spherical | 3 μm or 5 μm, spherical | 3 μm or 5 μm, spherical | 3 μm or 5 μm, spherical |
| Pore Size | 100 Å | 100 Å | 100 Å | 100 Å | 100 Å |
| Surface Area | 300 m2/g | 300 m2/g | 300 m2/g | 300 m2/g | 300 m2/g |
| Carbon Load | 20% | 12% | 15% | 8% | n/a |
| End-Cap | yes | yes | yes | yes | n/a |
| pH Range | 2.5 to 8.0 | 2.5 to 8.0 | 2.0 to 8.0 | 2.5 to 8.0 | 2.5 to 8.0 |
| Maximum Temperature | 80 °C | 80 °C | 80 °C | 80 °C | 80 °C |
Figure 1: Over 1,000 injections and Roc HPLC columns will still offer reliable performance, regardless of which dimension your method calls for.
Figure 2: Add a Roc HPLC guard to further extend the life of your analytical column without impacting your retention, peak shape, or efficiency.
LC_GN0565
Peaks
| Peaks | Conc. (mg/mL) | |
|---|---|---|
| 1. | Uracil | 0.02 |
| 2. | Toluene | 3.00 |
| 3. | Naphthalene | 0.50 |
| 4. | Biphenyl | 0.06 |
Conditions
| Column | Roc C8 (cat.# 9533565) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dimensions: | 150 mm x 4.6 mm ID | ||||||||||||
| Particle Size: | 5 µm | ||||||||||||
| Pore Size: | 100 Å | ||||||||||||
| Guard Column: | Roc C8 10 mm, 4.0 mm ID, 5 µm (cat.# 953350210) | ||||||||||||
| Temp.: | 30 °C | ||||||||||||
| Standard/Sample | Custom mix | ||||||||||||
| Diluent: | 50:50 Acetonitrile:water | ||||||||||||
| Inj. Vol.: | 2 µL | ||||||||||||
| Mobile Phase | |||||||||||||
| A: | Water | ||||||||||||
| B: | Acetonitrile | ||||||||||||
|
| Detector | UV @ 254 nm |
|---|---|
| Instrument | HPLC |
Figure 3: From one column to the next, one lot to the next, Roc columns provide results you can trust time and time again.
Reversed Phase
LC_GN0562
Peaks
| Peaks | tR (min) | |
|---|---|---|
| 1. | p-Tolunitrile | 3.7 |
| 2. | 4-Butylbenzoic acid | 5.2 |
| 3. | 3,4-Dimethylanisole | 7.3 |
| 4. | Mefenamic acid | 8.1 |
| 5. | p-Xylene | 9.7 |
Conditions
| Column | Roc C18 (cat.# 9534565) |
|---|---|
| Dimensions: | 150 mm x 4.6 mm ID |
| Particle Size: | 5 µm |
| Pore Size: | 100 Å |
| Temp.: | 35 °C |
| Standard/Sample | |
| Inj. Vol.: | 5 µL |
| Mobile Phase | 0.05% Formic acid in water:0.05% Formic acid in acetonitrile (40:60) |
| Flow: | 1.0 mL/min |
| Detector | UV/Vis @ 220 nm |
|---|---|
| Cell Temp: | 35 °C |
| Instrument | HPLC |
Normal Phase
LC_GN0563
Peaks
| Peaks | tR (min) | |
|---|---|---|
| 1. | Benzene | 3.5 |
| 2. | Nitrobenzene | 4.1 |
| 3. | 1,3,5-Trinitrobenzene | 5.5 |
| 4. | 2,4-Dinitrotoluene | 7.4 |
Conditions
| Column | Roc Cyano (cat.# 953631E) |
|---|---|
| Dimensions: | 100 mm x 3.0 mm ID |
| Particle Size: | 3 µm |
| Pore Size: | 100 Å |
| Temp.: | 40 °C |
| Standard/Sample | |
| Inj. Vol.: | 1 µL |
| Mobile Phase | Water:acetonitrile (80:20) |
| Flow: | 0.6 mL/min |
| Detector | UV/Vis @ 254 nm |
|---|---|
| Cell Temp: | 40 °C |
| Instrument | HPLC |
Roc HPLC Columns from Restek Perform Better Than or Equal To Columns from Other Vendors
| Columns | Analyte | tR | Area | Height | USP Tailing | Asymmetry (10%) | k’ | Plate Number | Resolution |
| Roc | Ethylparaben | 3.252 | 1,407,609 | 281,358 | 1.176 | 1.148 | 1.182 | 9,738 | 12.5 |
| Ethinyl Estradiol | 5.410 | 1,869,684 | 234,346 | 1.075 | 1.064 | 2.631 | 10,264 | ||
| Vendor A | Ethylparaben | 3.060 | 1,424,621 | 215,698 | 1.907 | 1.608 | 1.013 | 6,732 | 10.1 |
| Ethinyl Estradiol | 4.889 | 1,860,659 | 223,879 | 1.311 | 1.217 | 2.217 | 8,575 | ||
| Vendor B | Ethylparaben | 2.873 | 1,426,068 | 319,850 | 1.143 | 1.124 | 0.866 | 9,706 | 9.9 |
| Ethinyl Estradiol | 4.307 | 1,867,049 | 287,414 | 1.064 | 1.057 | 1.797 | 10,031 | ||
| Vendor C | Ethylparaben | 2.763 | 1,413,099 | 315,080 | 1.262 | 1.217 | 0.932 | 8,643 | 11.9 |
| Ethinyl Estradiol | 4.580 | 1,868,724 | 270,662 | 1.143 | 1.122 | 2.203 | 9,700 | ||
| Vendor D | Ethylparaben | 3.157 | 2,939,187 | 357,541 | 1.159 | 0.965 | 1.084 | 4,478 | 12.2 |
| Ethinyl Estradiol | 5.816 | 1,771,785 | 182,056 | 1.301 | 1.232 | 2.839 | 8,954 | ||
| Vendor E | Ethylparaben | 3.873 | 1,498,446 | 244,642 | 1.172 | 1.134 | 1.221 | 9,348 | 13.7 |
| Ethinyl Estradiol | 6.839 | 1,781,453 | 174,955 | 1.080 | 1.063 | 2.921 | 9,963 |
Figure 4: Count on Roc HPLC columns from Restek for outstanding chromatographic performance.
Roc HPLC Column
Vendor A
Vendor B
Vendor C
Vendor D
Vendor E
Chromatographic conditions for Table I and Figure 4
All columns are C18 stationary phase (5 µm, 150 x 4.6 mm). Conditions are as follows. Mobile phase: water:acetonitrile (1:1); Flow rate: 1 mL/min; Injection volume: 25 µL; Instrument: HPLC with UV detector, 280 nm; Sample: 200 µg/mL ethinyl estradiol and 50 µg/mL ethylparaben in water:acetonitrile (1:1).
Get more of what you want, and less of what you don’t, with Roc HPLC columns from Restek.
Author
GNSS2332
