Count Me In: patient-partnered research to address disparities for rare cancer patients.

Background: Approximately 25% of cancer patients are diagnosed with rare cancers and face unique challenges. Decentralized patient-partnered research efforts, like Count Me In provide an avenue for patients to participate in research that overcomes key barriers to address disparities in rare cancer research to accelerate discovery.

Objectives: Projects in metastatic breast cancer (The Metastatic Breast Cancer Project; MBCproject) and angiosarcoma (The Angiosarcoma Project; ASCproject) highlight disparities that exist for all cancer patients and underscore those that are compounded for rare cancer patients.

Systematic development of an UPLC-MS/MS method for the determination of tricyclic antidepressants in human urine.

Tricyclic antidepressants have been prescribed for the treatment of depression and other disorders since their discovery in the 1950s but have been replaced in recent decades by newer drugs with more favorable side effect profiles. However, for some patients and conditions, tricyclic antidepressants remain the drug of choice. A fast, sensitive, and robust UPLC-MS/MS method for the monitoring of amitriptyline, nortriptyline, imipramine, doxepin, and desipramine in human urine has been developed using a pre-defined and systematic method development approach.

Influence of stationary phase chemistry and mobile-phase composition on retention, selectivity, and MS response in hydrophilic interaction chromatography.

A comprehensive retention and selectivity characterization of several hydrophilic interaction chromatography (HILIC) stationary phases was performed with 28 test probes in order to study the influence of particle type, surface chemistry, and mobile-phase pH on chromatographic retention, selectivity, and MS response. Selectivity differences were compared for columns operated at both low and high pH, while ESI-MS was used to study the effects of mobile-phase pH on signal response. Additionally, acetone was explored as a potential alternative to ACN as the weak HILIC solvent.

Simultaneous analysis of morphine-related compounds in plasma using mixed-mode solid phase extraction and UltraPerformance liquid chromatography-mass spectrometry.

A bioanalytical method using mixed-mode solid phase extraction and UltraPerformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the analysis of morphine, morphine-3beta-glucuronide, morphine-6beta-glucuronide, 6-acetylmorphine, morphine N-oxide, and 10-hydroxymorphine in porcine plasma. All six compounds, along with four deuterated internal standards, were simultaneously extracted using mixed-mode strong cation exchange SPE in a 96-well microElution plate format. Due to analyte instability, a neutralizing solvent was used during the elution step to minimize degradation of 6-acetylmorphine.

Effects of extra-column band spreading, liquid chromatography system operating pressure, and column temperature on the performance of sub-2-microm porous particles.

The effects of extra-column band spreading, LC system operating pressure, and separation temperature were investigated for sub-2-microm particle columns using both a conventional HPLC system as well as a UPLC system. The contributions of both volume- and time-based extra-column effects were analyzed in detail. In addition, the performance difference between columns containing 2.

The application of novel 1.7 microm ethylene bridged hybrid particles for hydrophilic interaction chromatography.

An un-derivatized 1.7 microm ethylene bridged hybrid (BEH) particle was evaluated for its utility in retaining polar species in hydrophilic interaction chromatography (HILIC), and was compared to a 3 microm un-derivatized silica material. Retentivity as a function of mobile phase pH, polar modifier and ACN content was examined.

Differences in preparative loadability between the charged and uncharged forms of ionizable compounds.

Ionizable compounds experience a drastic difference in preparative loadability as a function of pH. It can be shown that the preparative loadability of a compound in the ionic form is by a factor of 20 or more inferior to the loadability of the same compound in the unionized form. In this paper, we demonstrate the reason for this behavior, and show practical applications of the principle.