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James Colter

Bio: James Colter is an academic researcher from University of Calgary. The author has contributed to research in topics: Population & Induced pluripotent stem cell. The author has an hindex of 2, co-authored 4 publications receiving 36 citations.

Papers
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Journal ArticleDOI
TL;DR: It is demonstrated that a vertical‐wheel bioreactor‐based bioprocess can provide optimal conditions for efficient, rapid generation of high‐quality hiPSCs to meet the demands for clinical manufacturing of therapeutic cell products.
Abstract: Human induced pluripotent stem cells (hiPSCs) have generated a great deal of attention owing to their capacity for self-renewal and differentiation into the three germ layers of the body. Their discovery has facilitated a new era in biomedicine for understanding human development, drug screening, disease modeling, and cell therapy while reducing ethical issues and risks of immune rejection associated with traditional embryonic stem cells. Bioreactor-based processes have been the method of choice for the efficient expansion and differentiation of stem cells in controlled environments. Current protocols for the expansion of hiPSCs use horizontal impeller, paddle, or rocking wave mixing method bioreactors which require large static cell culture starting populations and achieve only moderate cell fold increases. This study focused on optimizing inoculation, agitation, oxygen, and nutrient availability for the culture of hiPSCs as aggregates in single-use, low-shear, vertical-wheel bioreactors. Under optimized conditions, we achieved an expansion of more than 30-fold in 6 days using a small starting population of cells and minimal media resources throughout. Importantly, we showed that that this optimized bioreactor expansion protocol could be replicated over four serial passages resulting in a cumulative cell expansion of 1.06E6-fold in 28 days. Cells from the final day of the serial passage were of high quality, maintaining a normal karyotype, pluripotent marker staining, and the ability to form teratomas in vivo. These findings demonstrate that a vertical-wheel bioreactor-based bioprocess can provide optimal conditions for efficient, rapid generation of high-quality hiPSCs to meet the demands for clinical manufacturing of therapeutic cell products.

29 citations

Journal ArticleDOI
TL;DR: Li et al. as discussed by the authors reported the synthesis, chemical stability, and Li ion conductivity of a cubic garnet-type Li 5+−− x Ba x La 3−−−x Ta 2 O 12 (x ǫ = 0, 0.5, 1) in water and discuss the chemical stability in comparison to the corresponding Nb analogue.

26 citations

Journal ArticleDOI
TL;DR: In this article, the authors argue that one of the major challenges currently faced in improving the robustness of routine stem-cell biomanufacturing is in utilizing continuous, meaningful assessments of molecular and cellular characteristics from process to application.
Abstract: The translation of laboratory-scale bioprocess protocols and technologies to industrial scales and the application of human induced pluripotent stem cell (hiPSC) derivatives in clinical trials globally presents optimism for the future of stem-cell products to impact healthcare. However, while many promising therapeutic approaches are being tested in pre-clinical studies, hiPSC-derived products currently account for a small fraction of active clinical trials. The complexity and volatility of hiPSCs present several bioprocessing challenges, where the goal is to generate a sufficiently large, high-quality, homogeneous population for downstream differentiation-the derivatives of which must retain functional efficacy and meet regulatory safety criteria in application. It is argued herein that one of the major challenges currently faced in improving the robustness of routine stem-cell biomanufacturing is in utilizing continuous, meaningful assessments of molecular and cellular characteristics from process to application. This includes integrating process data with biological characteristic and functional assessment data to model the interplay between variables in the search for global optimization strategies. Coupling complete datasets with relevant computational methods will contribute significantly to model development and automation in achieving process robustness. This overarching approach is thus crucially important in realizing the potential of hiPSC biomanufacturing for transformation of regenerative medicine and the healthcare industry.

10 citations


Cited by
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Journal ArticleDOI
TL;DR: Garnet-type electrolyte has been considered one of the most promising and important solid-state electrolytes for batteries with potential benefits in energy density, electrochemical stability, high temperature stability, and safety, and this Review will survey recent development of garnet- type LLZO electrolytes.
Abstract: Solid-state batteries with desirable advantages, including high-energy density, wide temperature tolerance, and fewer safety-concerns, have been considered as a promising energy storage technology to replace organic liquid electrolyte-dominated Li-ion batteries. Solid-state electrolytes (SSEs) as the most critical component in solid-state batteries largely lead the future battery development. Among different types of solid-state electrolytes, garnet-type Li7La3Zr2O12 (LLZO) solid-state electrolytes have particularly high ionic conductivity (10-3 to 10-4 S/cm) and good chemical stability against Li metal, offering a great opportunity for solid-state Li-metal batteries. Since the discovery of garnet-type LLZO in 2007, there has been an increasing interest in the development of garnet-type solid-state electrolytes and all solid-state batteries. Garnet-type electrolyte has been considered one of the most promising and important solid-state electrolytes for batteries with potential benefits in energy density, electrochemical stability, high temperature stability, and safety. In this Review, we will survey recent development of garnet-type LLZO electrolytes with discussions of experimental studies and theoretical results in parallel, LLZO electrolyte synthesis strategies and modifications, stability of garnet solid electrolytes/electrodes, emerging nanostructure designs, degradation mechanisms and mitigations, and battery architectures and integrations. We will also provide a target-oriented research overview of garnet-type LLZO electrolyte and its application in various types of solid-state battery concepts (e.g., Li-ion, Li-S, and Li-air), and we will show opportunities and perspectives as guides for future development of solid electrolytes and solid-state batteries.

511 citations

Journal ArticleDOI
TL;DR: In this article, the importance of solid fast lithium ion conductors, advantages of lithium garnets over other ceramic lithium ion conductsors and understanding different strategies on synthesis of the garnet-like structural compounds.

275 citations

Journal ArticleDOI
TL;DR: In this study, an excellent stability in neutral and strongly basic solutions was observed when using the cubic Li7 La3 Zr2 O12 garnet as a Li-stable solid electrolyte as a separator in aqueous lithium batteries.
Abstract: Batteries with an aqueous catholyte and a Li metal anode have attracted interest owing to their exceptional energy density and high charge/discharge rate. The long-term operation of such batteries requires that the solid electrolyte separator between the anode and aqueous solutions must be compatible with Li and stable over a wide pH range. Unfortunately, no such compound has yet been reported. In this study, an excellent stability in neutral and strongly basic solutions was observed when using the cubic Li7 La3 Zr2 O12 garnet as a Li-stable solid electrolyte. The material underwent a Li(+) /H(+) exchange in aqueous solutions. Nevertheless, its structure remained unchanged even under a high exchange rate of 63.6 %. When treated with a 2 M LiOH solution, the Li(+) /H(+) exchange was reversed without any structural change. These observations suggest that cubic Li7 La3 Zr2 O12 is a promising candidate for the separator in aqueous lithium batteries.

120 citations

Journal ArticleDOI
TL;DR: In this article, the relationship between ion exchange and Li-population per unit cell was deduced for garnet oxides within ion-exchange process H+/Li+ ion exchange of cubic LLNZO powder is performed continuously in distilled water and products with various exchange levels are obtained via this simple method FTIR spectra show the evolution of H-O bonding through the ion exchange process, consistent with a preferential replacement of octahedrally coordinated Li.

103 citations

Journal ArticleDOI
TL;DR: In this article, an overview of the chemical and electrochemical stability of lithium-based garnets against moisture/humidity, aqueous solutions, carbon dioxide, sulfur, and metallic lithium are analyzed.

93 citations