share:

66th ASMS Conference on Mass Spectrometry and Allied Topics

Restek at ASMS 2018
Restek at ASMS 2018

RESTEK TECHNICAL POSTERS

Monday, June 4
LC_17 Affecting Selectivity and HILIC Retention on a FluoroPhenyl Stationary Phase
Xiaoning Lu (presenter), Frances Carroll, Shun-Hsin Liang, Sharon Lupo, Ty Kahler, Susan Steinike, Paul Connolly
Restek Corporation
For more information, email Xiaoning Lu.
Download a PDF of the full presentation.
Read abstract

In this study, we have set out to explore the retention mechanisms of the FluoroPhenyl stationary phase. The FluoroPhenyl phase may be described as having mixed-mode and/or HILIC retention and selectivity. HILIC and mixed-mode capabilities offer retention mechanisms that vary, or are orthogonal to, typical reversed-phase columns like C18s. These chemical interactions are generally not well understood or easily demonstrated, which may be frustrating and leave chromatographers not using the phase to the fullest potential.

The FluoroPhenyl phase offers unique selectivity by incorporating strongly electronegative fluorine atoms on a phenyl ring. In addition to traditional reversed-phase dispersive interactions, this phase exhibits polar, cation-exchange, and HILIC retention mechanisms. Our focus in this presentation is on method changes, including temperature, mobile phase composition, acid strength and concentration, and how these changes affect the selectivity of targeted analytes. By demonstrating the influence of method changes on this phase, we aim to gather a better understanding of the interactions provided by the FluoroPhenyl phase and its use as a HILIC or mixed-mode phase.

LC_21 HILIC, Polar, and Shape Selectivity of a FluoroPhenyl Phase
Gary Stidsen (presenter), Frances Carroll, Shun-Hsin Liang, Sharon Lupo, Ty Kahler, Sue Steinike, Paul Connolly
Restek Corporation
For more information, email Gary Stidsen.
Download a PDF of the full presentation.
Read abstract

The FluoroPhenyl stationary phase has long been marketed as a phase that offers alternative, or orthogonal, selectivity to a C18. The FluoroPhenyl phase offers unique selectivity by incorporating strongly electronegative fluorine atoms on a phenyl ring. In addition to the traditional reversed-phase dispersive interactions, this phase also exhibits shape selective, polar, cation exchange, and even HILIC retention mechanisms, which aid in selectivity for specific analytes.

In this presentation, we aim to demonstrate the useful and alternate retention of the FluoroPhenyl stationary phase. We chose several relevant target analytes that we will use to illustrate the unique retention characteristics of the FluoroPhenyl phase when used in either HILIC or reversed-phase mode. All of these analytes have been pursued due to either poor retention, poor resolution, or both on a traditional C18 phase.

Tuesday, June 5
LC_36 Rapid Profiling and Quantification of 17 Bile Acids in Human Plasma by LC-MS/MS
Connor Flannery (presenter), Dan Li, Frances Carroll, Shun-Hsin Liang, Ravali Alagandula, Justin Steimling, Landon Wiest, Ty Kahler, Sue Steinike, Paul Connolly
Restek Corporation
For more information, email Connor Flannery.
Download a PDF of the full presentation.
Read abstract

Bile acids are a group of major catabolic products of cholesterol. They are important biomarkers for signaling potential harmful side effects for new drug development. Quantitation of bile acids in matrices proves to be very challenging due to a number of factors, including, the similarity of structures, varying polarities and stereochemistries, limited fragmentation for unconjugated bile acids in the mass spectrometer, high endogenous levels, and matrix effects caused by phospholipids or triglycerides. In this study, a rapid, robust, selective, and reliable LC-MS/MS method was established and validated in human plasma using a Raptor C18 column with baseline separation of 17 bile acids in 6 minutes.

Wednesday, June 6
LC_27 Analysis of Immunosuppressive Drugs from Whole Blood by LC-MS/MS
Paul Connolly (presenter)1, Shun-Hsin Liang1, Sharon Lupo1, Frances Carroll1, Justin Steimling1, Ty Kahler1, Susan Steinike1, Dananjaya Kalu Appulage2
1Restek Corporation, 2University of Texas at Arlington
For more information, email Paul Connolly.
Download a PDF of the full presentation.
Read abstract

The success of organ transplant therapy depends in large part on the accurate and timely analysis of immunosuppressive drugs. In this study, we developed a fast, accurate method for the analysis of cyclosporin A, tacrolimus, sirolimus, and everolimus in whole blood. The method pairs a single precipitation step with LC-MS/MS analysis using a Raptor Biphenyl column. A fast, 3-minute analysis time was obtained with no interference from matrix components. Excellent results were obtained for linearity, robustness, accuracy, and precision, demonstrating that the method is suitable for high-throughput therapeutic drug monitoring.

LC_30 A Novel Solution for EtG/EtS Analysis in Human Urine by LC-MS/MS
Dave Bell (presenter), Justin Steimling, Shun-Hsin Liang, Dan Li, Landon Wiest, Sharon Lupo, Ty Kahler, Frances Carroll, Susan Steinike, Paul Connolly
Restek Corporation
For more information, email Dave Bell.
Download a PDF of the full presentation.
Read abstract

Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are unique biomarkers of alcohol use. EtG and EtS analysis offers many advantages for abstinence monitoring including the detection window, stability in stored specimens, and specificity. EtG and EtS are both polar, making them difficult to retain via reversed-phase chromatography. Both compounds are also very sensitive to matrix interferences which can result in being unable to achieve low limits of detection and can also make quantitation impossible. In this study, a simple dilute-and-shoot method was developed and validated for the analysis of EtG and EtS in human urine by LC-MS/MS.

LC_34 Analysis of Fentanyl and Its Analogues in Human Urine by LC-MS/MS
Rob Freeman (presenter), Shun-Hsin Liang, Justin Steimling, Landon Wiest, Dan Li, Ravali Alagandula, Frances Carroll, Ty Kahler, Sue Steinike, Paul Connolly
Restek Corporation
For more information, email Rob Freeman.
Download a PDF of the full presentation.
Read abstract

Synthetic opioid drugs, such as fentanyl and sufentanil, have very high analgesic potency. Abuse of these prescription opioids and their illicit analogues is a growing public health problem. In this study, a simple dilute-and-shoot method was developed with an analysis time of 3.5 minutes for fentanyl, norfentanyl, acetyl fentanyl, alfentanil, butyryl fentanyl, carfentanil, remifentanil, and sufentanil in human urine by LC-MS/MS using a Raptor Biphenyl column.

Visit the ASMS 2018 website.