People
Principal Investigator
Guillermo Bazan
Title
Professor
Degree
PhD in Chemistry MIT; Postdoctoral Fellow at Caltech
B. Sc in Chemistry (Summa Cum Laude), University of Ottawa
Research Interests
Living Materials, Gels for Energy Storage, Bioimaging
Office Location
S9-08-02C
Biography
Professor Bazan is the Provost Chair at and is a member of the Departments of Chemistry and Chemical and Biomolecular Engineering. He also holds an appointment at the Department of Pharmacology in the Yong Loo Lin School of Medicine. He has published over 770 publications (> 55500 citations, H-index: 123).
His awards and recognitions include 2019 Clarivate Highly Cited Researcher, 2017 ISI Highly Cited Scientists in Materials Science, Frontiers in Chemistry Named Lecture, Case Western Reserve University, Professor of the Chang Jiang Scholars, Fellow of the Royal Society of Chemistry, Fellow of the American Association for the Advancement of Science, American Chemical Society Cope Scholar Award, and the Bessel Award, Humboldt Foundation.
Five startup companies have been founded by graduate students or postdocs during their studies in the Bazan group (Sirigen, Apeel, Next Energies, Xiretsa, and Acoearela). Over forty of previous postgraduate students and postdoctoral fellows now lead successful academic or national research lab positions
Selected Publications
- Vazquez, RJ, et al, Conjugated polyelectrolyte/bacteria living composites in carbon paper for biocurrent generation, Macromolecular Rapid Communications, 2100840, 2022.
- Limwongyut, J., et al, Amide moieties modulate the antimicrobial activities of conjugated oligoelectrolytes against gram-negative bacteria, ChemistryOpen, 11, e202100260, 2022.
- Quek, G, et al, Conjugated polyelectrolytes: underexplored materials for pseudocapacitive energy storage, Advanced Materials, 2104206, 2022.
- Quek, G, et al, Pseudocapacitive conjugated polyelectrolyte/2D electrolyte hydrogels with enhanced physico-electrochemical properties, Advanced Electronic Materials, 2100942, 2022.
- Tiihonen, A, et al, Predicting antimicrobial activity of conjugated oligoelectrolyte olecules via machine learning, Journal of the American Chemical Society, 143, 18917, 2021. Gillet, AJ, et al, The role of charge recombination to triplet excitons in organic solar cells, Nature, 597, 7878, 2021.
- Su, YD, A living biotic-abiotic composite that can switch function between current generation and electrochemical energy storage, Advanced Functional Materials, 31, 2007351, 2020.
I-FIM Publications:
2024 |
Leng, Xuanye; Chen, Siyu; McCuskey, Samantha R; Zhang, Yixin; Chan, Samuel J W; Quek, Glenn; Costa, Mariana C F; Zhang, Pengxiang; Wu, Jiqiang; Nikolaev, Konstantin G; Bazan, Guillermo C; Novoselov, Kostya S; Andreeva, Daria V DNA-rGO Aerogel Bioanodes with Microcompartmentalization for High-Performance Bioelectrochemical Systems ADVANCED ELECTRONIC MATERIALS, 2024, DOI: 10.1002/aelm.202400137. @article{ISI:001217766900001, title = {DNA-rGO Aerogel Bioanodes with Microcompartmentalization for High-Performance Bioelectrochemical Systems}, author = {Xuanye Leng and Siyu Chen and Samantha R McCuskey and Yixin Zhang and Samuel J W Chan and Glenn Quek and Mariana C F Costa and Pengxiang Zhang and Jiqiang Wu and Konstantin G Nikolaev and Guillermo C Bazan and Kostya S Novoselov and Daria V Andreeva}, doi = {10.1002/aelm.202400137}, times_cited = {0}, issn = {2199-160X}, year = {2024}, date = {2024-05-10}, journal = {ADVANCED ELECTRONIC MATERIALS}, publisher = {WILEY}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {Bioelectrochemical systems (BES) have garnered significant attention for their applications in renewable energy, microbial fuel cells, biocatalysis, and bioelectronics. In BES, bioelectrodes are used to facilitate extracellular electron transfer among microbial biocatalysts. This study is focused on enhancing the efficiency of these processes through microcompartmentalization, a technique that strategically organizes and segregates microorganisms within the electrode, thereby bolstering BES output efficiency. The study introduces a deoxyribonucleic acid (DNA)-based reduced graphene oxide (rGO) aerogel engineered as a bioanode to facilitate microorganism compartmentalization while providing an expanded biocompatible surface with continuous conductivity. The DNA-rGO aerogel is synthesized through the self-assembly of graphene oxide and DNA, with thermal reduction imparting lightweight structural stability and conductivity to the material. The DNA component serves as a hydrophilic framework, enabling precise regulation of compartment size and biofunctionalization of the rGO surface. To evaluate the performance of this aerogel bioanode, measurements of current generation are conducted using Shewanella oneidensis MR-1 bacteria as a model biocatalyst. The bioanode exhibits a current density reaching up to 1.5 A.m(-2), surpassing the capabilities of many existing bioanodes. With its abundant microcompartments, the DNA-rGO demonstrates high current generation performance, representing a sustainable approach for energy harvesting without reliance on metals, polymers, or heterostructures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Bioelectrochemical systems (BES) have garnered significant attention for their applications in renewable energy, microbial fuel cells, biocatalysis, and bioelectronics. In BES, bioelectrodes are used to facilitate extracellular electron transfer among microbial biocatalysts. This study is focused on enhancing the efficiency of these processes through microcompartmentalization, a technique that strategically organizes and segregates microorganisms within the electrode, thereby bolstering BES output efficiency. The study introduces a deoxyribonucleic acid (DNA)-based reduced graphene oxide (rGO) aerogel engineered as a bioanode to facilitate microorganism compartmentalization while providing an expanded biocompatible surface with continuous conductivity. The DNA-rGO aerogel is synthesized through the self-assembly of graphene oxide and DNA, with thermal reduction imparting lightweight structural stability and conductivity to the material. The DNA component serves as a hydrophilic framework, enabling precise regulation of compartment size and biofunctionalization of the rGO surface. To evaluate the performance of this aerogel bioanode, measurements of current generation are conducted using Shewanella oneidensis MR-1 bacteria as a model biocatalyst. The bioanode exhibits a current density reaching up to 1.5 A.m(-2), surpassing the capabilities of many existing bioanodes. With its abundant microcompartments, the DNA-rGO demonstrates high current generation performance, representing a sustainable approach for energy harvesting without reliance on metals, polymers, or heterostructures.
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Pham, Minh Nhat; Su, Chun-Jen; Huang, Yu-Ching; Lin, Kun-Ta; Huang, Ting-Yu; Lai, Yu-Ying; Wang, Chen-An; Liaw, Yong-Kang; Lin, Ting-Han; Wan, Keng-Cheng; He, Cheng-Tai; Huang, Yu-Han; Yang, Yong-Ping; Wei, Hsuan-Yen; Jeng, U-Ser; Ruan, Jrjeng; Luo, Chan; Huang, Ye; Bazan, Guillermo C; Hsu, Ben B Y Forming Long-Range Order of Semiconducting Polymers through Liquid-Phase Directional Molecular Assemblies MACROMOLECULES, 57 (8), pp. 3544-3556, 2024, DOI: 10.1021/acs.macromol.3c02188. @article{ISI:001203973200001, title = {Forming Long-Range Order of Semiconducting Polymers through Liquid-Phase Directional Molecular Assemblies}, author = {Minh Nhat Pham and Chun-Jen Su and Yu-Ching Huang and Kun-Ta Lin and Ting-Yu Huang and Yu-Ying Lai and Chen-An Wang and Yong-Kang Liaw and Ting-Han Lin and Keng-Cheng Wan and Cheng-Tai He and Yu-Han Huang and Yong-Ping Yang and Hsuan-Yen Wei and U-Ser Jeng and Jrjeng Ruan and Chan Luo and Ye Huang and Guillermo C Bazan and Ben B Y Hsu}, doi = {10.1021/acs.macromol.3c02188}, times_cited = {0}, issn = {0024-9297}, year = {2024}, date = {2024-04-12}, journal = {MACROMOLECULES}, volume = {57}, number = {8}, pages = {3544-3556}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {Intermolecular interactions are crucial in determining the morphology of solution-processed semiconducting polymer thin films. However, these random interactions often lead to disordered or short-range ordered structures. Achieving long-range order in these films has been a challenge due to limited control over microscopic interactions in current techniques. Here, we present a molecular-level methodology that leverages spatial matching of intermolecular dynamics among solutes, solvents, and substrates to induce a directional molecular assembly in weakly bonded polymers. Within the optimized dynamic scale of 2.5 & Aring; between polymer side chains and self-assembled monolayers (SAMs) on nanogrooved substrates, our approach transforms random aggregates into unidirectional fibers with a remarkable increase in the anisotropic stacking ratio from 1 to 11. The Flory-Huggins-based molecular stacking model accurately predicts the transitioning order on various SAMs, validated by morphological and spectroscopic observations. The enhanced structural ordering spans over 3 orders of magnitude in length, rising from the smallest 7.3 nm random crystallites to >14 mu m unidirectional fibers on submillimeter areas. Overall, this study provides insights into the control of complex intermolecular interactions and offers enhanced molecular-level controllability in solution-based processes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Intermolecular interactions are crucial in determining the morphology of solution-processed semiconducting polymer thin films. However, these random interactions often lead to disordered or short-range ordered structures. Achieving long-range order in these films has been a challenge due to limited control over microscopic interactions in current techniques. Here, we present a molecular-level methodology that leverages spatial matching of intermolecular dynamics among solutes, solvents, and substrates to induce a directional molecular assembly in weakly bonded polymers. Within the optimized dynamic scale of 2.5 & Aring; between polymer side chains and self-assembled monolayers (SAMs) on nanogrooved substrates, our approach transforms random aggregates into unidirectional fibers with a remarkable increase in the anisotropic stacking ratio from 1 to 11. The Flory-Huggins-based molecular stacking model accurately predicts the transitioning order on various SAMs, validated by morphological and spectroscopic observations. The enhanced structural ordering spans over 3 orders of magnitude in length, rising from the smallest 7.3 nm random crystallites to >14 mu m unidirectional fibers on submillimeter areas. Overall, this study provides insights into the control of complex intermolecular interactions and offers enhanced molecular-level controllability in solution-based processes.
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Quek, Glenn; Ohayon, David; Ng, Pei Rou; Bazan, Guillermo C A Cross-linked n-Type Conjugated Polymer with Polar Side Chains Enables Ultrafast Pseudocapacitive Energy Storage SMALL, 20 (24), 2024, DOI: 10.1002/smll.202401395. @article{ISI:001186407400001, title = {A Cross-linked n-Type Conjugated Polymer with Polar Side Chains Enables Ultrafast Pseudocapacitive Energy Storage}, author = {Glenn Quek and David Ohayon and Pei Rou Ng and Guillermo C Bazan}, doi = {10.1002/smll.202401395}, times_cited = {0}, issn = {1613-6810}, year = {2024}, date = {2024-03-18}, journal = {SMALL}, volume = {20}, number = {24}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Pseudocapacitors bridge the performance gap between batteries and electric double-layer capacitors by storing energy via a combination of fast surface/near-surface Faradaic redox processes and electrical double-layer capacitance. Organic semiconductors are an emerging class of pseudocapacitive materials that benefit from facile synthetic tunability and mixed ionic-electronic conduction. Reported examples are mostly limited to p-type (electron-donating) conjugated polymers, while n-type (electron-accepting) examples remain comparatively underexplored. This work introduces a new cross-linked n-type conjugated polymer, spiro-NDI-N, strategically designed with polar tertiary amine side chains. This molecular design aims to synergistically increase the electroactive surface area and boost ion transport for efficient ionic-electronic coupling. Spiro-NDI-N demonstrates excellent pseudocapacitive energy storage performance in pH-neutral aqueous electrolytes, with specific capacitance values of up to 532 F g-1 at 5 A g-1 and stable cycling over 5000 cycles. Moreover, it maintains a rate capability of 307 F g-1 at 350 A g-1. The superior pseudocapacitive performance of spiro-NDI-N, compared to strategically designed structural analogues lacking either the cross-linked backbone or polar side chains, validates the essential role of its molecular design elements. More broadly, the design and performance of spiro-NDI-N provide a novel strategy for developing high-performance organic pseudocapacitors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Pseudocapacitors bridge the performance gap between batteries and electric double-layer capacitors by storing energy via a combination of fast surface/near-surface Faradaic redox processes and electrical double-layer capacitance. Organic semiconductors are an emerging class of pseudocapacitive materials that benefit from facile synthetic tunability and mixed ionic-electronic conduction. Reported examples are mostly limited to p-type (electron-donating) conjugated polymers, while n-type (electron-accepting) examples remain comparatively underexplored. This work introduces a new cross-linked n-type conjugated polymer, spiro-NDI-N, strategically designed with polar tertiary amine side chains. This molecular design aims to synergistically increase the electroactive surface area and boost ion transport for efficient ionic-electronic coupling. Spiro-NDI-N demonstrates excellent pseudocapacitive energy storage performance in pH-neutral aqueous electrolytes, with specific capacitance values of up to 532 F g-1 at 5 A g-1 and stable cycling over 5000 cycles. Moreover, it maintains a rate capability of 307 F g-1 at 350 A g-1. The superior pseudocapacitive performance of spiro-NDI-N, compared to strategically designed structural analogues lacking either the cross-linked backbone or polar side chains, validates the essential role of its molecular design elements. More broadly, the design and performance of spiro-NDI-N provide a novel strategy for developing high-performance organic pseudocapacitors.
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Zhang, Kaixi; Limwongyut, Jakkarin; Moreland, Alex S; Wei, Samuel Chan Jun; Min, Tania Jim Jia; Sun, Yan; Shin, Sung Jae; Kim, Su-Young; Jhun, Byung Woo; Pethe, Kevin; Bazan, Guillermo C An anti-mycobacterial conjugated oligoelectrolyte effective against Mycobacterium abscessus SCIENCE TRANSLATIONAL MEDICINE, 16 (735), 2024, DOI: 10.1126/scitranslmed.adi7558. @article{ISI:001168145300003, title = {An anti-mycobacterial conjugated oligoelectrolyte effective against \textit{Mycobacterium abscessus}}, author = {Kaixi Zhang and Jakkarin Limwongyut and Alex S Moreland and Samuel Chan Jun Wei and Tania Jim Jia Min and Yan Sun and Sung Jae Shin and Su-Young Kim and Byung Woo Jhun and Kevin Pethe and Guillermo C Bazan}, doi = {10.1126/scitranslmed.adi7558}, times_cited = {0}, issn = {1946-6234}, year = {2024}, date = {2024-02-21}, journal = {SCIENCE TRANSLATIONAL MEDICINE}, volume = {16}, number = {735}, publisher = {AMER ASSOC ADVANCEMENT SCIENCE}, address = {1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA}, abstract = {Infections caused by nontuberculous mycobacteria have increased more than 50% in the past two decades and more than doubled in the elderly population. Mycobacterium abscessus (Mab), one of the most prevalent of these rapidly growing species, is intrinsically resistant to numerous antibiotics. Current standard-of-care treatments are not satisfactory, with high failure rate and notable adverse effects. We report here a potent anti-Mab compound from the flexible molecular framework afforded by conjugated oligoelectrolytes (COEs). A screen of structurally diverse, noncytotoxic COEs identified a lead compound, COE-PNH2, which was bactericidal against replicating, nonreplicating persisters and intracellular Mab.COE-PNH2 had low propensity for resistance development, with a frequency of resistance below 1.25 x 10(-9) and showed no detectable resistance upon serial passaging. Mechanism of action studies were in line with COE-PNH2 affecting the physical and functional integrity of the bacterial envelope and disrupting the mycomembrane and associated essential bioenergetic pathways. Moreover, COE-PNH2 was well-tolerated and efficacious in a mouse model of Mab lung infection. This study highlights desirable in vitro and in vivo potency and safety index of this COE structure, which represents a promising anti-mycobacterial to tackle an unmet medical need.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Infections caused by nontuberculous mycobacteria have increased more than 50% in the past two decades and more than doubled in the elderly population. Mycobacterium abscessus (Mab), one of the most prevalent of these rapidly growing species, is intrinsically resistant to numerous antibiotics. Current standard-of-care treatments are not satisfactory, with high failure rate and notable adverse effects. We report here a potent anti-Mab compound from the flexible molecular framework afforded by conjugated oligoelectrolytes (COEs). A screen of structurally diverse, noncytotoxic COEs identified a lead compound, COE-PNH2, which was bactericidal against replicating, nonreplicating persisters and intracellular Mab.COE-PNH2 had low propensity for resistance development, with a frequency of resistance below 1.25 x 10(-9) and showed no detectable resistance upon serial passaging. Mechanism of action studies were in line with COE-PNH2 affecting the physical and functional integrity of the bacterial envelope and disrupting the mycomembrane and associated essential bioenergetic pathways. Moreover, COE-PNH2 was well-tolerated and efficacious in a mouse model of Mab lung infection. This study highlights desirable in vitro and in vivo potency and safety index of this COE structure, which represents a promising anti-mycobacterial to tackle an unmet medical need.
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2023 |
Jiang, Yan; Vazquez, Ricardo Javier; Mccuskey, Samantha R; Yip, Benjamin Rui Peng; Quek, Glenn; Ohayon, David; Kundukad, Binu; Wang, Xuehang; Bazan, Guillermo C Recyclable Conjugated Polyelectrolyte Hydrogels for Pseudocapacitor Fabrication ACS APPLIED MATERIALS & INTERFACES, 16 (16), pp. 19968-19976, 2023, DOI: 10.1021/acsami.3c13137. @article{ISI:001158885000001, title = {Recyclable Conjugated Polyelectrolyte Hydrogels for Pseudocapacitor Fabrication}, author = {Yan Jiang and Ricardo Javier Vazquez and Samantha R Mccuskey and Benjamin Rui Peng Yip and Glenn Quek and David Ohayon and Binu Kundukad and Xuehang Wang and Guillermo C Bazan}, doi = {10.1021/acsami.3c13137}, times_cited = {1}, issn = {1944-8244}, year = {2023}, date = {2023-12-27}, journal = {ACS APPLIED MATERIALS & INTERFACES}, volume = {16}, number = {16}, pages = {19968-19976}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {In alignment with widespread interest in carbon neutralization and sustainable practices, we disclose that conjugated polyelectrolyte (CPE) hydrogels are a type of recyclable, electrochemically stable, and environmentally friendly pseudocapacitive material for energy storage applications. By leveraging ionic-electronic coupling in a relatively fluid medium, one finds that hydrogels prepared using a fresh batch of an anionic CPE, namely, Pris-CPE-K, exhibit a specific capacitance of 32.6 +/- 6.6 F g(-1) in 2 M NaCl and are capable of 80% (26.1 +/- 6.5 F g(-1)) capacitance retention after 100,000 galvanostatic charge-discharge (GCD) cycles at a current density (J) of 10 A g(-1). We note that equilibration under a constant potential prior to GCD analysis leads to the K+ counterions in the CPE exchanging with Na+ and, thus, the relevant active material Pris-CPE-Na. It is possible to remove the CPE material from the electrochemical cell via extraction with water and to carry out a simple purification through dialysis to produce a recycled material, namely Re-CPE-Na. The recycling workup has no significant detrimental impact on the electrochemical performance. Specifically, Re-CPE-Na hydrogels display an initial specific capacitance of 26.3 +/- 1.2 F g(-1) (at 10 A g(-1)) and retain 77% of the capacitance after a subsequent 100,000 GCD cycles. Characterization by NMR, FTIR, and Raman spectroscopies, together with XPS and GPC measurements, revealed no change in the structure of the backbone or side chains. However, rheological measurements gave evidence of a slight loss in G ' and G ''. Overall, that CPE hydrogels display recyclability argues in favor of considering them as a novel materials platform for energy storage applications within an economically viable circular recycling strategy.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In alignment with widespread interest in carbon neutralization and sustainable practices, we disclose that conjugated polyelectrolyte (CPE) hydrogels are a type of recyclable, electrochemically stable, and environmentally friendly pseudocapacitive material for energy storage applications. By leveraging ionic-electronic coupling in a relatively fluid medium, one finds that hydrogels prepared using a fresh batch of an anionic CPE, namely, Pris-CPE-K, exhibit a specific capacitance of 32.6 +/- 6.6 F g(-1) in 2 M NaCl and are capable of 80% (26.1 +/- 6.5 F g(-1)) capacitance retention after 100,000 galvanostatic charge-discharge (GCD) cycles at a current density (J) of 10 A g(-1). We note that equilibration under a constant potential prior to GCD analysis leads to the K+ counterions in the CPE exchanging with Na+ and, thus, the relevant active material Pris-CPE-Na. It is possible to remove the CPE material from the electrochemical cell via extraction with water and to carry out a simple purification through dialysis to produce a recycled material, namely Re-CPE-Na. The recycling workup has no significant detrimental impact on the electrochemical performance. Specifically, Re-CPE-Na hydrogels display an initial specific capacitance of 26.3 +/- 1.2 F g(-1) (at 10 A g(-1)) and retain 77% of the capacitance after a subsequent 100,000 GCD cycles. Characterization by NMR, FTIR, and Raman spectroscopies, together with XPS and GPC measurements, revealed no change in the structure of the backbone or side chains. However, rheological measurements gave evidence of a slight loss in G ' and G ''. Overall, that CPE hydrogels display recyclability argues in favor of considering them as a novel materials platform for energy storage applications within an economically viable circular recycling strategy.
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