Synthesis and Use of a New Covalently Bonded C18 Modified Carbon Clad Microporous Zirconia for Fast High Temperature Separations by Peter W. Carr, Clayton V. McNeff, Dwight R. Stoll, Danielle R. Hawker, Angelos Kyrlidis (Cabot), Greg Gaudet (Cabot) 2001 ZirChrom Separations, Inc.
UTLINE Analytical Advantages of Column Stability Development of a New Type of RP Column: DiamondBond-C18 Selectivity Comparison of DiamondBond-C18 with Luna C18 (2) Silica and ther Columns Applications Conclusions
Analytical Advantages of Column Stability Extraordinary Chemical Stability ph Stability Thermal Stability ph < 1 ph > 13 Lower Pressure Drop Less rganic Solvent Thermally ptimize Selectivity Cleaning with Conc. Acid Ion Supression for Acids Ion Supression for Amines Sanitation/ Depyrogenation Less Wear and Tear Higher Flow Rate: Fast Analysis More Robust Analysis Easier Method Development
Patented Synthesis of Carbon Clad Zirconia Lewis Acid Site Zr Zr Zr Zr Zr Zr H H Bulk Zirconia
A New Class of Stationary Phase Media General approach - Cabot Corporation (Billerica, MA): functionalizing agent X-R-Y X reacts with surface Y = functional group X is typically a diazonium salt NH 2 Y + 2 HX + NaN 2 = XN N Y + 2 H 2 + NaX + N N + Y Carbon Clad Zirconia Diazonium Salt Modified Carbon Clad Zirconia
Chemical Structure of DiamondBond-C18 DS DiamondBond-C18 CH 3 CH 3 CH 3 CH 3 CH 3 ( ) 16 10 ( ) 10 16 ( ) 10 16 10 10 CH 3 CH 3 CH 3 CH 3 CH 3 CH Si CH CH 3 CH 3 CH Si CH CH 3 H H H C C C C C C C C C C C C C C Zirconia Substrate Silica Substrate
Stability Testing of 8 DiamondBond 7 6 k' 5 4 3 2 1 0 k' Butylbenzene (0.5M Nitric Acid) k' Butylbenzene (1.0M NaH) k' Butylbenzene (200 Degrees Celsius) 0 250 500 750 1000 1250 2000 Column Volumes LC Conditions: Base Stability DiamondBond TM Phase A, 30 x 4.6 mm id; Mobile phase, 50/50 ACN/Water; Flow rate, 1.0 ml/min.; Temperature, 30 o C; Injection volume, 5ul; Detection at 254nm. Acid Stability DiamondBond TM Phase A, 50 x 4.6 mm id; Mobile phase, 50/50 ACN/Water; Flow rate, 1.0 ml/min.; Temperature, 30 o C; Injection volume, 5ul; Detection at 254nm. Temperature Stability DiamondBond TM Phase B, 50 x 4.6 mm id; Mobile phase, 50/50 ACN/Water; Flow rate, 1.0 ml/min.; Temperature, 30 o C; Injection volume, 5ul; Detection at 254nm.
Phase Stability Comparison at High ph* ZirChrom-PBD ph12.0 Gammabond RP-1 ph 12.0 k' Propranolol 9.00 8.00 7.00 6.00 5.00 4.00 3.00 2.00 1.00 Luna C18 (2) ph 10.0 Extend C18 Rapid Res. ph 11.5 Xterra RP18 ph 12.0 DiamondBond-C18 ph 12.5 0.00 0 2000 4000 6000 8000 10000 12000 14000 16000 Column Volumes of Mobile Phase * Column names are the trademarks of their respective manufacturers.
Chromatographic Selectivity Comparison of DiamondBond-C18 to ther Stable RP Phases LC Conditions: Mobile phase, 40/60 Acetonitrile/50mM phosphate at ph 3.2, Flow rate, 1.0 ml/min., Temperature = 30 o C, Detection at 254nm, 5µl Injection volume. (LC-GC, Vol 13, No. 9, September 1995, 720-726.) Columns Tested*: DiamondBond-C18, Luna C18 (2), ZirChrom-PBD, Gammabond RP-1, Xterra RP18, Polymer Labs PLRP-S * Column names are the trademarks of their respective manufacturers.
22 Non-electrolyte Solutes Benzene Toluene Ethylbenzene p-xylene Propylbenzene Butylbenzene Cl Br Cl B romobenzene p-d ichlorobenzene A nisole M ethy lbenzoate N apthalene A cetophenone N 2 CN N 2 N 2 Cl Benzonitrile Nitrobenzene p-nitrotoluene p-nitrobenzyl Chloride Benzophenone Cl H H NH H H H Benzylalcohol 3-Phenyl Propanol N-Benzyl Formamide Phenol p-chlorophenol
Normalized Selectivity Comparison*: DiamondBond-C18 and Luna C18 (2) 1.500 1.000 0.500 0.000-0.500-1.000-1.500 Luna C18 (2) DiamondBond-C18 Log (solute k'/benzene k') benzyl formamide benzyl alcohol phenol 3-phenyl propanol p-chlorophenol acetophenone benzonitrile nitrobenzene methylbenzoate anisole benzene p-chlorotoluene p-nitrobenzyl chloride toluene benzophenone bromobenzene ethylbenzene p-xylene napthalene p-dichlorobenzene propyl benzene butyl benzene Solute * Column names are the trademarks of their respective manufacturers.
Regression Data from log k vs. log k Plots for All Columns versus Luna C18 (2)* Column vs. Luna C18 (2) R 2 ZirChrom-PBD 0.985 Gammabond RP-1 0.981 Xterra RP18 0.972 Polymer Labs PLRP-S 0.963 DiamondBond-C18 0.889 * Column names are the trademarks of their respective manufacturers.
Applications Benzodiazepams - Anti-anxiety Drugs Norm. 600 500 ph = 7.0 3 4 400 300 200 1 2 100 0 0 2.5 5 7.5 10 12.5 15 17.5 20 22.5 min LC Conditions: Column, 50 x 4.6 DiamondBond TM -C18; Mobile phase, 20 to 40% THF, 20 min ramp in 50mM potassium phosphate ph 7.0; Flow rate, 1.0 ml/min; Temperature, 30 o C; Injection volume, 2 ul; Detection at 254 nm; Solute concentration 0.25 mg/ml; Solutes, 1=xazepam, 2=Temazepam, 3=Diazepam, 4=Medazepam.
DiamondBond-C18 Selectivity* a) 150 x 4.6 mm DS b) 100 x 4.6 mm DiamondBond-C18 1,2 1 2 Ethylbenzene p-xylene 0 1 2 3 4 5 6 7 8 9 min 0 1 2 3 4 5 6 7 8 9 min LC Conditions: a) Column, 150 x 4.6 Zorbax Eclipse XDB-C8 S/N: USRK010769; Mobile phase, 65/35 ACN/Water; Temperature, 30 o C; Flow rate, 1.0 ml/min.; Injection volume, 5 ul; Detection at 254 nm; Solutes: 1=Ethylbenzene, 2=p-xylene. b) Column, 100 x 4.6 DiamondBond-C18, D082401A; Mobile phase, 37.5/5/57.5 ACN/THF/Water; Temperature, 60 o C; all other conditions the same as a). * Column names are the trademarks of their respective manufacturers.
mau 250 200 150 100 Separation of Anticonvulsants on DiamondBond -C18 and Hypercarb* T 3 1 2 4 (N = 8,700) a) DiamondBond-C18 5 (N = 9,400) 50 0 mau 175 150 125 100 75 50 0 1 2 3 4 5 6 7 3 1 2 b) Hypercarb 5 (N = 4,900) 4 (N = 5,400) min 25 0 0 1 2 3 4 5 6 7 LC Conditions: a) DiamondBond-C18 100 x 4.6; Mobile phase 25/75 THF/50mM Ammonium phosphate, ph 7.0; Flow rate, 1.0 ml/min.; Temperature, 50 o C; Injection volume, 0.5 ul; Detection at 220nm; Solutes: 1=Primidone, 2=Metharbital, 3=Mephenytoin, 4=Phenobarbital, 5=Phenytoin. b) Hypercarb 100 x 4.6; Mobile phase, 31/69 THF/50mM Ammonium phosphate, ph 7.0; all other conditions the same as in a). min * Column names are the trademarks of their respective manufacturers.
pioids mau 160 140 3 ph = 11.0 120 100 80 1 2 4 60 40 20 0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 LC Conditions: Column, 100 x 4.6 DiamondBond TM -C18; Mobile phase, 26.5/73.5 THF/20mM Ammonium phosphate, ph 11.0; Flow rate, 1.0 ml/min.; Temperature, 40 o C; Injection volume, 1.0 ul; Detection at 220nm; Solutes: 1=Naloxone, 2=Codeine, 3=Ethylmorphine, 4=xycodone min
Fast Separations Non-Steroidal Anti-Inflammatories mau 80 70 1 ph = 1.75 60 50 2 40 3 4 30 20 10 0 0 1 2 3 4 5 6 min LC Conditions: Column, 100 x 4.6 DiamondBond TM -C18; LC Conditions: Mobile phase, 50/50 ACN/50mM Phosphoric acid, ph 1.75; Flow rate, 1.0 ml/min.; Temperature, 65 o C; Injection volume, 1.0 ul; Detection at 254nm; Solutes: 1=Acetominaphen, 2=Ketoprofen, 3=Ibuprofen, 4=Naproxen
Future Directions Ion-Exchangers Polar Bonded Phases (NPLC) Chiral Stationary Phases (CSPs) Reversed-Phases for Biomolecules Nonporous Preparative
Conclusions DiamondBond TM -C18 is an ultra-durable and efficient carbonbased HPLC stationary phase. DiamondBond TM -C18 is stable at the extremes of ph and at column temperatures as high as 200 o C. DiamondBond TM -C18 had the most different selectivity relative to conventional DS phases for the 22 selected non-ionizable compounds. DiamondBond TM -C18 s durability allows for high and low ph separations for improved peak shape. DiamondBond TM s chemistry is as flexible as silane chemistry and in the future will be used to produce a broad family of novel ultradurable phases.