We explore the interactions of V(III) -, V(IV) -, and V(V) -2,6-pyridinedicarboxylic acid (dipic) complexes with model membrane systems and whether these interactions correlate with the blood-glucose-lowering effects of these compounds on STZ-induced diabetic rats. Two model systems, dipalmitoylphosphatidylcholine (DPPC) Langmuir monolayers and AOT (sodium bis(2-ethylhexyl)sulfosuccinate) reverse micelles present controlled environments for the systematic study of these vanadium complexes interacting with self-assembled lipids. Results from the Langmuir monolayer studies show that vanadium complexes in all three oxidation states interact with the DPPC monolayer; the V(III) -phospholipid interactions result in a slight decrease in DPPC molecular area, whereas V(IV) and V(V) -phospholipid interactions appear to increase the DPPC molecular area, an observation consistent with penetration into the interface of this complex. Investigations also examined the interactions of V(III) - and V(IV) -dipic complexes with polar interfaces in AOT reverse micelles. Electron paramagnetic resonance spectroscopic studies of V(IV) complexes in reverse micelles indicate that the neutral and smaller 1:1 V(IV) -dipic complex penetrates the interface, whereas the larger 1:2 V(IV) complex does not. UV/Vis spectroscopy studies of the anionic V(III) -dipic complex show only minor interactions. These results are in contrast to behavior of the V(V) -dipic complex, [VO2 (dipic)](-) , which penetrates the AOT/isooctane reverse micellar interface. These model membrane studies indicate that V(III) -, V(IV) -, and V(V) -dipic complexes interact with and penetrate the lipid interfaces differently, an effect that agrees with the compounds' efficacy at lowering elevated blood glucose levels in diabetic rats.

The correct use of micropipettes has been investigated in an undergraduate, introductory lab experiment intended for chemistry and biology majors. This lab experiment involves the use of micropipettes for accurately mixing, transferring, and applying a specific amount of dye to a cotton bandana. The data resulting from this experiment is a color wheel that displays the amount of dye transferred based on the volume of the micropipette set by the student. Student learning outcomes for this experiment include the ability to choose the correct micropipette for the volume needed, set the correct volume on a micropipette, properly draw up solutions, and use proper dispensing technique. The development of experimental foresight and improvement in students' planning was an unintentional learning outcome. A prelab survey assessing students' confidence in accurately using micropipettes shows that a majority of first-year students had not used micropipettes in high school (85%) but did in their firstsemester science course (60%) before taking this course. The majority of those students have confidence in their ability to choose the correct micropipette, draw up the liquid, and dispense it properly. There was less confidence in setting the correct volume on the micropipette. The postlab results show that some students still had issues in setting volumes on micropipettes correctly and in dispensing the liquid. Additionally, the postsurvey suggests that setting the correct volume on the micropipette was the most learned skill from performing the lab. Overall, after performing the lab exercise, 92% of the students were confident in their ability to choose the correct micropipette and load and dispense liquid properly compared to 62% before performing the exercise.