Figures & data
Figure 1. Noninvasive wNMR measurements of vaccines. (a). Daptacel®, Engerix-B®, and VAQTA® (left to right) vials contained 0.5-, 1.0-, and 1.0- mL aqueous vaccine suspension respectively. (b). The label mostly obscures the view of the suspension inside the vials, but the bottom view of vials laying on their side shows the suspension inside the vials. (c). Measurements were made on sealed, intact vials with labels, that were lowered, via a thread looped around the vial neck, into an inner and outer glass NMR tube situated inside the NMR probe. (d). View of vial inside inner and outer glass NMR tubes. (e). Temperature-controlled benchtop NMR relaxometer (Resonance Systems GmbH) with an arrow indicating the bore location for sample lowering into probe.
Figure 2. Vaccine sedimentation monitored by wNMR for 2 hr 40 min. R2(1H2O) was measured approximately every 3 min 14 sec over the course of vaccine sedimentation for Daptacel® (a), Engerix-B® (b), and VAQTA® (c) where the unstressed vaccines (black) were compared with F/T-stressed vaccines that were exposed to subzero temperatures (red). Daptacel® and Engerix-B® were observed to have frozen, while VAQTA® was not frozen upon subzero temperature exposure. Sedimentation was monitored at 5°C on thawed (if frozen) vials fully dispersed at the beginning of the measurement.
Figure 3. Vaccine sedimentation of the same set of unstressed and stressed vials measured two years apart by wNMR. The R2(1H2O, T) of (a) Daptacel®, (b) Engerix-B®, and (c) VAQTA®. Unstressed vaccines: black (Sept. 2022) and green (July-Oct. 2020); Stressed vaccines: red (Sept. 2022) and blue (July-Oct. 2020). F/T-stressed Daptacel® and Engerix-B® were observed to have solidly frozen, while VAQTA® was not frozen upon subzero temperature exposure. For each vial, its two sedimentation profiles measured two years apart almost superimpose each other.
