October 2004 Meeting

Solute Attributes and Molecular Interactions Contributing to Unique Retentions of a Fluorinated Stationary Phase for LC/MS

The October 2004 CSSC meeting will be held at Bristol-Myers Squibb in Wallingford, CT.
Registration will begin on September 15, 2004.
To register, use our secure online system by clicking here.
To use the online system, you must be registered as a user.
Clicking here to become a registered user.

Date:

Tuesday, October 12, 2004

Location:

Bristol-Myers Squibb, Wallingford, CT

Speaker:

David S. Bell
Supelco Inc.

Agenda:

5:30 - 6:30 pm Social Hour
6:30 - 7:30 pm Dinner
7:30 - 8:30 pm Seminar

Cost:

$25 ($15 Students and Emeritus)

Registration
Deadline:

Friday, October 8, 2004


Abstract Biography Directions Register	Home Current Meetings Past Meetings

Abstract:
Authors: David S. Bell (1,2) and A. Daniel Jones (1)

(1) Department of Chemistry
The Pennsylvania State University
University park, PA 16802
(2) Supelco Division of Sigma-Aldrich
595 North Harrison Road
Bellefonte, PA 16823

The combination of high performance liquid chromatography (HPLC or LC) and mass spectrometry (MS) has become the dominant analytical tool in analysis of pharmaceuticals and for metabolite analysis. LC/MS, however, suffers from serious limitations in analysis of polar, low molecular mass (< 500 Da) metabolites, which are often poorly retained on common HPLC stationary phases. Inadequate chromatography can result in significant matrix effects and poor quantitation. In traditional chromatographic analysis, ion-pair reagents are often added to mobile phases to provide retention for polar, ionizable analytes. These reagents, however, are generally non-volatile and suppress ionization in LC/MS experiments. Other separation techniques such as capillary electrophoresis are also suitably employed for retention and separation of such analytes, but the predominantly aqueous solvents and high ionic strength buffers employed are less amenable to MS interfacing than many liquid chromatographic systems. It is therefore desirable to design stationary phases capable of retaining polar analytes using mobile phase constituents suitable for mass spectral analysis.

Fluorinated, silica-based stationary phases have shown unique retention for small, polar analytes. In particular, pentafluorophenylpropyl (PFPP) phases exhibit both reversed-phase and normal-phase retention for polar analytes, which has shown to be dependent on mobile phase composition. At lower percentages of organic modifier, solute retention resembles that of classical reversed-phase systems. At higher percentages of organic, however, behavior more typical of normal-phase separations is observed with increasing proportions of organic modifier. The normal-phase behavior is observed using mobile phase components common to reversed-phase LC that are highly compatible with mass spectrometry. To date, the retention mechanisms responsible for the normal-phase behavior and the fundamental properties of analytes that exhibit this phenomenon remain unclear.

The retention characteristics for several classes of pharmaceutically relevant compounds on both PFPP and traditional C18 bonded stationary phases will be reported. Retention characteristics are related to analyte structure and the impact of the unique retention on the PFPP phase for LC/MS experiments is highlighted. Results from fundamental studies designed at establishing the molecular interactions responsible for the observed retention will be presented.

Biography:

David S. Bell, Applications Laboratory Supervisor, Supelco Inc., Bellefonte, PA

After receiving his B.S. degree from SUNY Plattsburgh in 1989, Dave gained employment within the pharmaceutical industry where he was involved in analytical method development using various forms of chromatography and electrophoresis for 8 years. For the past 7 years, working directly in the chromatography industry, Dave has focused his efforts on the design, development and application of HPLC stationary phases. Of special interest is the understanding of molecular interactions that contribute to retention and selectivity in chromatographic processes. He is currently completing his graduate work toward a Ph.D. in Analytical Chemistry at The Pennsylvania State University where the focus has been the development of mass spectrometry platforms for the analysis of small, polar molecules.

Directions:

Bristol-Myers Squibb Company
Pharmaceutical Research Institute
5 Research Parkway
Wallingford, CT 06492

From the South (New York)

I-95 Northbound to Exit 48 in New Haven which is the beginning of I-91 North. Get off Exit 15 from I-91 and take right at the traffic light onto Route 68 East. Take a left at the first traffic light onto Research Parkway, which is about 3/10 of a mile from the exit. The Wallingford facility is the first building on the right.

From the North

I-91 Southbound to Exit 15. Take left at light at end of ramp. Take left at second traffic light (approximately 1/2 mile) onto Research Parkway. The Wallingford facility is the first building on the right.

Via Route 15 (Hutchinson River/Merritt/Wilber Cross Parkways)

Exit 66 in Wallingford. Turn left at light at the end of the ramp onto Route 5 Southbound. Stay on Route 5 for approximately 1/2 mile and make left onto the access road for Route 68. Turn left at light onto Route 68 (Eastbound). Follow Route 68 East past the Courtyard Hotel on the left and continue past the entrances to I-91.Turn left at the first traffic light past I-91 (not including the entrance to I-91 Northbound) onto Research Parkway. Bristol-Myers Squibb is the first building on the right.

Via I-95 (New England Expressway)

Take I-95 (Northbound) to Exit 48 (left exit) onto I-91 (Northbound). Stay on I-91 for about 15 miles to Exit 15 (Route 68). Turn right off Exit 15 onto Route 68 (Eastbound towards Durham). Turn left at first traffic light onto Research Parkway. Bristol-Myers Squibb is the first building on the right.


	CSSC Home
Copyright © 2002-2007 -- Cristina Manolescu -- All Rights Reserved