KCAS will be represented at the 17th WRIB’s (Workshops on Recent Issues in Bioanalysis) upcoming meeting in Orlando Disney Springs by three poster presentations being given by our talented scientists, Bryan Parmentier, Alvin Evans, and Jack Rogers.

Two of these posters were created in collaboration with other scientific organizations, and all three will focus on topics at the forefront of our industry, especially at WRIB. We invite you to attend these presentations during the event in Florida, and we would also invite you to ask any questions you have of the presenters using the form below, leading up to the meeting.

We look forward to seeing you at the following presentations:

Development of a LC-MS/MS method for the quantitation of urea in human plasma using surrogate matrix and hydrophilic interaction chromatography
Bryan Parmentier, Sr Principal Scientist, KCAS
(poster made with GDIT’s DynPort Vaccine Company and NIAID)


Endogenous urea measurement in plasma is often utilized as a control marker to account for dilutions that occur during sample collection or processing when other types of study matrix samples are obtained within the same project (e.g., bronchoalveolar fluid). Due to the low molecular weight of urea (60.06 g/mol), it is known to diffuse rapidly and uniformly across the peripheral blood and epithelial lining. The high endogenous urea concentrations (~ 275 μg/mL) in plasma, combined with its highly polar properties, are significant barriers to simple LC/MS/MS approaches such as organic protein precipitation extraction, reversed phase liquid chromatography, and use of the actual study sample matrix for standard curve preparation. In addition, there is significant potential for interferences from other low molecular weight species. Thus, more unconventional approaches as gas chromatography, derivatization or isotope dilution methods have been routinely applied for the quantitation of urea in biological fluids.

“Urea is well known to the audience of WRIB, but it is still one of the molecules that is very hard to measure without advanced techniques. Here we have developed a high throughput assay that is both quick to extract and analyze, and straightforward. I imagine a number of the WRIB audience will appreciate what we’ve done here and want to attend.” – Bryan Parmentier, KCAS

ELISA-based Assay for Quantitation of ADC Drug PYX-201 in Rat and Monkey Plasma
Alvin Evans, Sr Scientist, KCAS
(poster made with Pyxis Oncology, Inc.)


Antibody-drug conjugates are a class of biopharmaceuticals that combine the specificity of monoclonal antibodies with small molecule anti-cancer therapeutics. This rapidly growing class of therapeutics is changing the landscape of chemotherapy. Understanding the modeling and development of antibody-drug conjugates can be challenging due to the incorporation of parameters to measure the intact antibody-drug complex, the antibody, and the dissociation drug agents in the body. EDB + FN is a complete type III repeat of 91 amino acids and is abundant in most human solid tumor tissues. PYX-201 is a novel, investigational antibody-drug conjugate targeting EDB + FN in the tumor microenvironment for the treatment of advanced solid tumors. PYX-201 is composed of an EDB targeting monoclonal antibody (mAb) L19-kK183C-K94R-K290C-hG1, a fully human IgG1 antibody engineered with reactive cysteines to enable drug antibody ratio (DAR) of 4 with site-specific conjugation of a cleavable linker payload mcValCitPABC_Aur0101 (pelidotin). PYX-201 binds specifically to EDB + FN protein and delivers the potent cytotoxic payload Aur0101 precisely to the tumor microenvironment. To quantify PYX-201 in both sprague dawley rat plasma and cynomolgus monkey plasma, two pharmacokinetic Enzyme-Linked Immunosorbent Assays were developed and validated.

“Anyone interested in Oncology therapeutics targeting solid tumors through the use of antibody drug conjugates will not want to miss this presentation.” – Alvin Evans, KCAS

Optimization of Calibration Curve Design via Hybrid In Silico/In Vitro Analysis of Serial and Non-Serial Dilution Schemes
Jack Rogers, Scientist I, KCAS


Calibration curves for ligand binding assays are typically prepared using one of two approaches: a classic serial dilution scheme originating from a single working stock solution, or a non-serial dilution scheme where each standard is spiked individually from one or more pre-dilutions. Though both types of schemes are accepted and employed within the industry, the comparative assessment between the two methods is often overlooked during method development, and a systematic, side-by-side comparison of the two approaches is currently lacking in the literature to our knowledge. Recent white paper guidance suggests that the non-serial approach of spiking calibrators directly at each level, while not strictly required, may be preferable as it will add an additional level of control and allow spiking accuracy to be monitored. Building from this guidance, this investigation compares several serial and non-serial dilution schemes through two complementary approaches – computational simulation to characterize and refine dilution scheme options, followed by an experimental set of accuracy and precision (A&P) assays to assess the top two choices identified in silico. The relative strengths and drawbacks of each option are elucidated, providing further rationale for opting into a non-serial dilution scheme.

“Those attending WRIB will really be the ideal audience for this presentation, as it is one of the first demonstrations that there is a difference between these two dilution schemes. Findings like these are the ones that move assay performance in the right direction.” – Jack Rogers, KCAS

If you have any questions about the these presentations or any others given by KCAS, please use the form below. Thank you!


Scroll to Top