Dialysis, Albumin Binding, and Competitive Binding: A Laboratory Lesson Relating Three Chemical Concepts to Healthcare Jennifer P. Domingo, † Mohammed Abualia, † Diana Barragan, † Lianne Schroeder, † Donald J. Wink, † Maripat King, ‡ and Ginevra A. Clark* ,† † Department of Chemistry, University of Illinois, Chicago, MC-111, 845 W. Taylor Street, Chicago, Illinois 60607, United States ‡ College of Nursing, University of Illinois, Chicago, MC-802, 845 S. Damen Street, Chicago, Illinois 60612, United States * S Supporting Information ABSTRACT: Introductory Chemistry laboratories must go beyond “cookbook” methods to illustrate how chemistry concepts apply to complex, real-world problems. In our case, we are preparing students to use their chemistry knowledge in the healthcare profession. The experiment described here explicitly models three important chemical concepts: dialysis of small molecules (dye), reversible binding (dye binding to albumin), and competitive binding (dye and a competitor binding to albumin). Moreover, each concept is intimately related to a physiological phenomenon: dialysis is used to treat renal failure, drugs travel in the blood bound to albumin, and competitive albumin binding is a common drug- drug interaction. In the context of this simple series of experiments, students create models, use evidence to validate their models, and finally use their understanding to describe physiological phenomena. This laboratory experiment was implemented in a 100- level course for predominantly prenursing majors. Student pre- and postlab models were examined, illustrating an improved conceptual understanding upon performing the lab and use of evidence to improve or support models. This experiment can be performed in 1 h, and can be adapted as a lecture demonstration. KEYWORDS: General Public, First Year Undergraduate/General, High School/Introductory Chemistry, Biochemistry, Laboratory Instruction, Inquiry Based/Discovery Learning, Equilibrium, Membranes, Proteins/Peptides, Drugs/Pharmaceuticals ■ INTRODUCTION In transforming the undergraduate curriculum to a more student-centered approach, it is important to consider the goals and interests of the students. Students preparing to enter health-related fields may not understand how their chemistry instruction is relevant to healthcare, or understand foundational chemistry topics well enough to apply them. By developing laboratories that illustrate biological systems, then asking students to develop their own models and understandings, we hope to bridge the gap between chemistry content knowledge and student career interests. This experiment models three concepts that have been identified as foundational in nursing practice: dialysis, reversible binding, and competitive binding. Several studies have surveyed nursing faculty, students, and practitioners to identify concepts that should be taught in chemistry courses. 1, 2 Dialysis consistently ranks highly, yet few lessons have been developed to clearly illustrate the concepts of dialysis, 3 or provide insight for students as to why these concepts are relevant in healthcare. This experiment provides a simple model for dialysis, which is related to kidney function and several other processes in human health. Further, in order for hydrophobic drugs to travel in the bloodstream, they bind to the serum protein albumin. 4 In the bound state, albumin acts as a reservoir; in the unbound state, drugs are able to pass through small pores in the capillary and reach their targets. 4 Finally, competitive albumin binding is a common reason for drug-drug incompatibility. For example, sulfonamide antibiotics should not be taken with blood thinners, as competitive binding can alter the effective concentration of either or both drugs in the bloodstream. This can result in high effective concentrations of blood thinner, which can contribute to major bleeding. In this experiment, students perform dialysis of a dye molecule in the presence or absence of albumin and in the presence of albumin with a competitive binder in order to model these three phenomena. This lab is part of a series of laboratories we are developing to teach fundamental concepts in chemistry that meet the needs of prehealth students using the MORE framework. 5 The curriculum is being developed with best practices in mind: explicitly stating conceptual goals, including reflective prompts, and allowing students time for discussion. 6 MORE, developed by Rickey and co-workers, 7 asks students to model a system of interest in both the macroscopic and molecular levels. In lab, Received: February 17, 2017 Revised: May 16, 2017 Laboratory Experiment pubs.acs.org/jchemeduc © XXXX American Chemical Society and Division of Chemical Education, Inc. A DOI: 10.1021/acs.jchemed.7b00131 J. Chem. Educ. XXXX, XXX, XXX-XXX