Recombinant adeno-associated virus serotype 9 (rAAV9) can specifically transduce muscle and neuronal tissues; thus, rAAV9 can potentially be used in gene therapy. However, rAAV9 is the most challenging rAAV serotype to purify. Traditionally, rAAV9 has been purified by ultracentrifugation, which is not scalable. We recently described a chromatographic purification protocol for rAAV1; this protocol can achieve scalable purifications. In this study, we attempted to optimize this protocol for purifying rAAV9 preparations, and we developed a novel, effective method for high-yield purification of rAAV9 using quaternary ammonium anion exchangers and size-exclusion chromatography. The final purified rAAV9 contained mainly three capsid proteins, as observed by SDS-PAGE. Furthermore, negative-stain electron microscopy demonstrated that 96.1% ± 1.1% of rAAV9 particles carried the viral genome containing the EGFP transgene, indicating that impurities and empty capsids can be eliminated with our purification protocol. The final rAAV9 titer obtained by our protocol totaled 2.5 ± 0.4 × 1015 viral genomes produced from ∼3.2 × 109 HEK293EB cells. We confirmed that our protocol can also be applied to purify other varied AAV genome constructs. Our protocol can scale up production of pure rAAV9, in compliance with current good manufacturing practice, for clinical applications in human gene therapy.

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The electrochemical properties of a lithium air secondary battery (LAB) cell incorporating CMK-3 or carbon replica (CR) as a highly ordered mesoporous carbon support material were examined under the condition of a current density of 0.1 mA/cm 2 with a voltage range of 2.0 to 4.2 V in a dry air atmosphere. The first discharge capacities of the LAB cell incorporating Pt 10 Ru 90 electrocatalyst/CMK-3 and CR were 103 and 1000 mAh/g, respectively. The cycle properties of the LAB cell incorporating Pt 10 Ru 90 electrocatalyst/CMK-3 was poor; in contrast, the one incorporating CR showed better cycle stability (828 mAh/g up to 9 cycles). These superior properties with CR are due to its larger surface area and larger total pore volume than those of CMK-3.

Power generation tests of pulse jet (PJ) rechargeable direct carbon fuel cells (PJ-RDCFCs), which supply small amounts of isooctane to the anode by pulse jetting, were conducted at different PJ supply frequency and for different PJ supply amount. PJ-RDCFCs could control power density by controlling the supply frequency. At 1 pulse/sec, power generation characteristics of PJ-RDCFCs approached flow-type. At lower supply frequency, power generation characteristics approached batch-type and fuel utilization becomes higher. Fuel utilization also became higher with decreasing PJ supply amount. In the reaction mechanism of a PJ-RDCFC, the contributing species for power generation might be hydrogen, carbon monoxide and hydrocarbons when the PJ supply frequency is high (≈1 pulse/sec). With decreasing supply frequency, carbon which has lower reactivity became to contribute to the power generation. In conclusion, the electrochemical reactions in the anode side in a PJ-RDCFC can be controlled by adjusting the pulse jet supply frequency.

Air electrodes with millimeter-order thickness for lithium air secondary batteries were prepared by loading electrode materials containing carbon and electrocatalyst into a single-layer nickel foam sheet or stacking three nickel-foam sheets loaded with the electrode materials. Discharge properties of the lithium air secondary battery cells incorporating these air electrodes were examined in 1 mol/l LiTFSA/TEGDME under a pure oxygen flow. The cell incorporating the air electrode with carbon loaded into the three-layer stack of nickel-foam sheets with total thickness of 3 mm showed a rather large discharge capacity of about 80 mAh/cm 2 compared to about 30 mAh/cm 2 for the cell with a carbon-only air electrode incorporating a single nickel-foam sheet with 3-mm thickness. The cell incorporating an air electrode loaded with Pt 10 Ru 90 electrocatalyst could be cycled under the condition of large cutoff capacities of 10 mAh/cm 2 at current density of 0.2 mA/cm 2 .