Purospher^® RP-18 endcapped

Excellent peak symmetry for both basic and strongly acidic compounds

Purospher^® RP-18 endcapped is a versatile HPLC column providing separations with excellent peak symmetry for both basic and strongly acidic compounds. Simply composed eluents could be employed for the separation of basic drugs. This results in shorter analysis time and increases laboratory productivity.

The excellent balance of chromatographic properties is the key for better separating complex samples with simple, neutral eluents. Purospher^® RP-18 endcapped is based upon a high purity, metal-free silica with a complete coverage of the silica surface with C18-ligands. This enables a peak-tailing free elution of acidic, basic, and chelating compounds. Key applications are the determination of various azo dyestuff amines and beta-blockers demonstrating the good resolution and high peak symmetry.

Additionally, the chemical stability of Purospher^® RP-18 endcapped is high. Mobile phase conditions at pH 8 could be applied for a long period of time without loss of performance.
Purospher^® RP-18 endcapped columns have excellent selectivity and column efficiency – allowing robust method development in R&D and QC.

Separation of Azo Dyestuff Amines
Column	LiChroCART 125-4 Purospher RP-18 endcapped, 5 µm
Mobile phase	A: Acetonitrile B: 20 mM Phosphate buffer, pH 7.0 (H3PO4 with ammonia)
Gradient	0.0 - 19.9 min 19.9 - 20.0 min 20.0 - 30.0 min	25%A 28 - 60% A 60% A
Flow rate	1.0 mL/min
Detection	UV 254 nm
Temperature	55°C
Inj. volume	10 µL
Sample	1. 2,4-Diaminoanisole 2. 2,4-Diaminotoluene 3. 4,4’-Oxydianiline 4. Benzidine 5. o-Toluidine 6. 4,4’-Diaminodiphenylmethane 7. p-Chloroaniline 8. p-Cresidine 9. 3,3’-Dimethoxybenzidine		10. 4,4’-Thiodianiline 11. 3,3’-Dimethylbenzidine 12. 2-Naphthylamine 13. 4-Chloro-o-toluidine 14. 2,4,5-Trimethylaniline 15. 4,4’-Diamino-3,3’-dimethyldiphenylmethane 16. 4-Aminobiphenyl 17. 3,3’-Dichlorobenzidine 18. 4,4’-Diamino-3,3’-dichlorodiphenylmethane