Multivalent Influenza vaccine production in HEK-293 cells in response to pandemic threats

Influenza virus infects millions of people every year worldwide, with elderly and very young people among the most critically affected. Strains that constitute a pandemic threat are characterized by the severity of the clinical manifestations and mortality rates and tend to require the urgent production of hundreds of millions of vaccine doses in very short periods of time. There is an evident need to develop new generations of influenza vaccines based on robust production systems such as mammalian or insect cell cultures. These systems may allow, in contrast to production in embryonated chicken eggs, a faster response capacity, a superior manufacturing process control and a more reliable and better characterized product. Please click Download on the upper right corner to see the full abstract

Development of scalable downstream processing platform for HEK293SF cell-based influenza vaccine production

Background: Research efforts during recent decades have demonstrated the suitability of mammalian cell culture platform for influenza vaccine production. Certainly, the potential of this system for a large-scale continuous vaccine manufacturing will enable a faster response to pandemic comparing with traditional egg-based production. Even though great advances have been achieved on the upstream processing of mammalian cell culture produced influenza vaccines, the downstream processing and quality of final product have still room for improvement or is still in development. Please click Download on the upper right corner to see the full abstract

Development of iridium-bismuth-oxide coatings for use in neural stimulating electrodes

Implantable neural prosthetics with stimulating electrodes is an increasingly-employed medical practice to treat neural disability. Further development of prosthetics to recover complex neuron function requires electrodes with higher capacity to delivery charge to neuron. Ir-oxide is currently considered as state-of-the-art stimulating electrode material. However, further improvement of its properties is needed. Consequently, in this work, addition of bismuth to Ir-oxide to produce IrxBi1-x-oxide coatings of various composition (x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) were fabricated by thermal deposition of their salts on a titanium substrate, and their charge-storage/delivery capacity, surface morphology, crystalline structure and biocompatibility was evaluated. The mixed metal oxides were characterized as consisting of multi-oxide states of Ir and Bi. It was found that only a 20mol.% addition of bismuth to Ir-oxide to produce Ir0.8Bi0.2-oixde yielded superior properties to Ir-oxide. This electrode exhibited a five-fold increase in charge storage capacity over the Ir-oxide electrode, yielding 26.8 mC/cm2. At the same time, this electrode yielded the lowest impedance at 1 kHz. The superior performance of Ir0.8Bi0.2-oixde was explained to originate from change in lattice structure upon introduction of Bi to Ir-oxide, which enables better access of H+ and OH- ions deeper into the oxide structure, thus yielding a higher charge storage capacity. The Ir0.8Bi0.2-oixde electrode also showed good stability and biocompatibility, which makes potentially a better candidate for neural stimulating electrodes than the current state-of-the-art Ir-oxide.Les prothèses neurales implantables avec électrodes de stimulation constituent une pratique médicale de plus en plus employée dans le traitement d'incapacité neurales. Le développement davantage de prothèses pour rétablir une fonction neuronale complexe nécessite des électrodes ayant une capacité plus élevée pour délivrer la charge au neurone. L'oxyde d'Ir est actuellement considéré comme un matériau d'électrode de stimulation supérieur. Cependant, une amélioration de ses propriétés est nécessaire. Pour cette raison, dans ce travail, l'addition de bismuth à l'oxyde de Ir pour produire des revêtements d'IrxBi1-x-oxydes de compositions diverses (x = 0, 0,2, 0,4, 0,6, 0,8 et 1,0) ont été fabriquées par le processus bien établi « décomposition thermique » de leurs sels sur des titane substrats, et leur capacité de stockage/livre de charge, leur morphologie de surface, leur structure cristalline et leur biocompatibilité ont été évalués. Les oxydes métalliques mixtes fabriquées dans le projet ont constituées d'Ir et de Bi selon des technique de caractérisation. Il a été constaté que seule une addition de 20% en moles de bismuth à l'oxyde d'Ir pour produire de l'Ir0.8Bi0.2-oxyde donnait des propriétés supérieures à celles de l'oxyde d'Ir. Cette électrode présentait une capacité de stockage cinq fois plus élevé que l'électrode en oxyde d'Ir, ce qui donnait 26.8mC/cm2. Au même temps, cette électrode produisait la plus faible impédance à 1 kHz. La performance supérieure d'Ir0.8Bi0.2-oixde est expliqué par le changement de structure du réseau lors de l'introduction de Bi dans l'oxyde d'Ir, ce qui permet un meilleur accès approfondi des ions H + et OH- à la structure de l'oxyde, produisant ainsi une capacité de stockage plus élevée. L'électrode Ir0.8Bi0.2-oxyde a également montré une bonne stabilité et une bonne biocompatibilité, ce qui fait en sorte que ce-dernier a la potentielle d'être un meilleur candidat pour les électrodes de stimulation neurale que l'oxyde d'Ir

Oriented Design of Transition-Metal-Oxide Hollow Multishelled Micropolyhedron Derived from Bimetal–Organic Frameworks for the Electrochemical Detection of Multipesticide Residues

Transition-metal oxides (TMOs) with a hollow multishelled structure have emerged as highly potential materials for high-performance electrochemical sensing, benefiting from their superior electronic conductivity, exceptionally large specific surface area, excellent stability, and electrochemistry properties. In particular, binary TMOs are expected to outperform unitary TMOs due to the synergistic effect of the different metals. Herein, MnCo2O4.5 hollow quadruple-shelled porous micropolyhedrons (MnCo2O4.5 HoQS-MPs) were prepared and employed to construct an ultrasensitive sensing platform for a multipesticide assay. Profiting from complex hollow interior structures and abundant active sites, the MnCo2O4.5 HoQS-MPs manifest outstanding electrochemical properties as electrode materials for the pesticide assay. The MnCo2O4.5 HoQS-MP-based biosensor demonstrated remarkable performance for monocrotophos, methamidophos, and carbaryl detection, with wide linear ranges, as well as low detection limits. This work unveils a new pathway for the ultrasensitive detection of pesticides and demonstrates tremendous potential for detecting other environmentally deleterious chemicals

Membrane chromatography-based downstream processing for cell-culture produced influenza vaccines

New influenza strains are constantly emerging, causing seasonal epidemics and raising concerns to the risk of a new global pandemic. Since vaccination is an effective method to prevent the spread of the disease and reduce its severity, the development of robust bioprocesses for producing pandemic influenza vaccines is exceptionally important. Herein, a membrane chromatography-based downstream processing platform with a demonstrated industrial application potential was established. Cell culture-derived influenza virus H1N1/A/PR/8/34 was harvested from benchtop bioreactor cultures. For the clarification of the cell culture broth, a depth filtration was selected as an alternative to centrifugation. After inactivation, an anion exchange chromatography membrane was used for viral capture and further processing. Additionally, two pandemic influenza virus strains, the H7N9 subtype of the A/Anhui/1/2013 and H3N2/A/Hong Kong/8/64, were successfully processed through similar downstream process steps establishing optimized process parameters. Overall, 41.3–62.5% viral recovery was achieved, with the removal of 86.3–96.5% host cell DNA and 95.5–99.7% of proteins. The proposed membrane chromatography purification is a scalable and generic method for the processing of different influenza strains and is a promising alternative to the current industrial purification of influenza vaccines based on ultracentrifugation methodologies