The Necessity of Using Heparin in an UltraTag™ RBC Kit when Tagging Blood for a Nuclear Medicine Study

The purpose of this research was to evaluate the need to use heparin when preparing an UltraTag red blood cell (RBC) kit for a nuclear medicine study. Methods: Nonheparinized blood samples (n = 15) and heparinized blood samples (n = 15) were added to UltraTag RBC kits. The samples were examined for macroscopic blood clotting and microscopic platelet clumping. As a control, samples with heparin (n = 15) and without heparin (n = 15) were used to help evaluate the effectiveness of the anticoagulant properties within the UltraTag RBC kit (sodium citrate) and whether those properties played a role in preventing clots or clumps. To detect clotting, the wooden applicator stick method was used. To detect clumping, blood smears were evaluated using a light microscope. The two samples were compared for presence of clots and clumps. Fisher exact testing was used to evaluate the significance of the data. Results: For the UltraTag RBC group, 2 of the 15 nonheparinized samples clotted and none of the 15 heparinized samples clotted; for the control group, 2 of the 15 nonheparinized samples clotted and none of the 15 heparinized samples clotted. For the Ultra-Tag RBC group, 3 of the 15 nonheparinized samples clumped and 3 of the 15 heparinized samples clumped; for the control group, 15 of the 15 nonheparinized samples clumped and 10 of the 15 heparinized samples clumped. Conclusion: When heparin is not used, the Ultra-Tag RBC kit is more likely to form clots. Heparin should always be used when preparing an Ultra-Tag RBC kit for a nuclear medicine study

Five-State Rotary Nanoswitch

In our quest to develop artificial multistate devices, we synthesized the nanomechanical switch <b>1</b> that is characterized by a tetrahedral core equipped with four pending arms. The rotary arm with its azaterpyridine terminal is intramolecularly coordinated to a zinc­(II) porphyrin station that is the terminus of another arm in <b>1</b>. The two other arms carry identical sterically shielded phenanthroline stations. The 2-fold alternate addition of a copper­(I) ion and [1,10]-phenanthroline (1 equiv each) results in the formation of five different switching states (State I→ State II→ State III→ State IV→ State V → State I), which force the toggling arm to move back and forth between the zinc­(II) porphyrin and phenanthroline stations separated by a distance of 25 Å. All switching states constitute clean single species, except for State III, and thus are fully characterized by spectroscopic methods and elemental analysis. Finally, the initial state of nanoswitch was reset by addition of cyclam for complete removal of the copper­(I) ions