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Maine A, Tamayo L, Leiva Á, González A, Ríos HE, Rojas-Romo C, Jara P, Araya-Durán I, González-Nilo F, Yazdani-Pedram M, Santana P, Leal M, González N, Briones X, Villalobos V, Urzúa M. Conformational Changes of Poly(Maleic Anhydride- alt-styrene) Modified with Amino Acids in an Aqueous Medium and Their Effect on Cytocompatibility and Hemolytic Response. ACS Appl Bio Mater 2023; 6:5333-5348. [PMID: 38032020 DOI: 10.1021/acsabm.3c00603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
The conformational changes of poly(maleic anhydride-alt-styrene) (PSMA) modified with different amino acids (PSMA-Aa) were studied in an aqueous medium as a function of ionic strength and pH. The specific viscosity of PSMA-Aa decreased with increasing salt concentration due to a more compact conformation. There was a decrease in surface tension with increasing concentrations of the modified polyelectrolyte having a greater effect for the PSMA modified with l-phenylalanine at pH 7.0, demonstrating a greater surface-active character. The conformational changes were also confirmed by molecular dynamics studies, indicating that PSMA-Aa exhibits a compact structure at pH 4.0 and a more extended structure at pH 7.0. On the other hand, the conformational changes of PSMA-Aa were related to its biological response, where the higher surface-active character of the PSMA modified with l-phenylalanine correlates very well with the higher hemolytic activity observed in red blood cells, in which the surface-active capacity supports lytic potency in erythrocytes. The cytocompatibility assays indicated that there were no significant cytotoxic effects of the PSMA-Aa. Additionally, in solvent-accessible surface area studies, it was shown that the carboxylate groups of the PSMA modified with l-phenylalanine are more exposed to the solvent at pH 7.0 and high salt concentrations, which correlates with lower fluorescence intensity, reflecting a loss of mitochondrial membrane potential. It is concluded that the study of the conformational changes in PE modified with amino acids is essential for their use as biomaterials and relevant to understanding the possible effects of PE modified with amino acids in biological systems.
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Affiliation(s)
- Arianne Maine
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Laura Tamayo
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Ángel Leiva
- Departamento de Química Física, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna N° 4860, Macul, Santiago 7821093, Chile
| | - Alex González
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Hernán E Ríos
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Carlos Rojas-Romo
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Paul Jara
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Ingrid Araya-Durán
- Center for Bioinformatics and Integrative Biology, Facultad de Ciencias para la Vida, Universidad Andrés Bello, Avenida República 330, Santiago 8370146, Chile
| | - Fernando González-Nilo
- Center for Bioinformatics and Integrative Biology, Facultad de Ciencias para la Vida, Universidad Andrés Bello, Avenida República 330, Santiago 8370146, Chile
| | - Mehrdad Yazdani-Pedram
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Olivos, 1007 Santiago, Chile
| | - Paula Santana
- Instituto de Ciencias Aplicadas, Facultad de Ingeniería, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, San Miguel, Santiago 8910123, Chile
| | - Matías Leal
- Center for Bioinformatics and Integrative Biology, Facultad de Ciencias para la Vida, Universidad Andrés Bello, Avenida República 330, Santiago 8370146, Chile
| | - Nicolás González
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Ximena Briones
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Olivos, 1007 Santiago, Chile
| | - Valeria Villalobos
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
| | - Marcela Urzúa
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Ñuñoa, Santiago 7800003,Chile
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Castro-Rodriguez JA, Fish EN, Montgomery ST, Kollmann TR, Iturriaga C, Shannon C, Karpievitch Y, Ho J, Chen V, Balshaw R, Ben-Othman R, Aniba R, Gidi-Yunge F, Hartnell L, Hancock DG, Pérez-Mateluna G, Urzúa M, Tebbutt SJ, García-Huidobro D, Perret C, Borzutzky A, Stick SM. Interferon β-1a ring prophylaxis to reduce household transmission of SARS-CoV-2: a cluster randomised clinical trial. EClinicalMedicine 2023; 62:102082. [PMID: 37538539 PMCID: PMC10393621 DOI: 10.1016/j.eclinm.2023.102082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/19/2023] [Accepted: 06/19/2023] [Indexed: 08/05/2023] Open
Abstract
Background Accumulating evidence indicates that an early, robust type 1 interferon (IFN) response to SARS-CoV-2 is important in determining COVID-19 outcomes, with an inadequate IFN response associated with disease severity. Our objective was to examine the prophylactic potential of IFN administration to limit viral transmission. Methods A cluster randomised open label clinical trial was undertaken to determine the effects of pegylated IFNβ-1a administration on SARS-CoV-2 household transmission between December 3rd, 2020 and June 29th, 2021. Index cases were identified from databases of confirmed SARS-CoV-2 individuals in Santiago, Chile. Households were cluster randomised (stratified by household size and age of index cases) to receive 3 doses of 125 μg subcutaneous pegylated IFNβ-1a (172 households, 607 participants), or standard care (169 households, 565 participants). The statistical team was blinded to treatment assignment until the analysis plan was finalised. Analyses were undertaken to determine effects of treatment on viral shedding and viral transmission. Safety analyses included incidence and severity of adverse events in all treatment eligible participants in the standard care arm, or in the treatment arm with at least one dose administered. Clinicaltrials.gov identifier: NCT04552379. Findings 5154 index cases were assessed for eligibility, 1372 index cases invited to participate, and 341 index cases and their household contacts (n = 831) enrolled. 1172 participants in 341 households underwent randomisation, with 607 assigned to receive IFNβ-1a and 565 to standard care. Based on intention to treat (ITT) and per protocol (PP) analyses for the primary endpoints, IFNβ-1a treatment did not affect duration of viral shedding in index cases (absolute risk reduction = -0.2%, 95% CI = -8.46% to 8.06%) and transmission of SARS-CoV-2 to household contacts (absolute risk reduction = 3.87%, 95% CI = -3.6% to 11.3%). Treatment with IFNβ-1a resulted in significantly more treatment-related adverse events, but no increase in overall adverse events or serious adverse events. Interpretation Based upon the primary analyses, IFNβ-1a treatment did not affect duration of viral shedding or the probability of SARS-CoV-2 transmission to uninfected contacts within a household. Funding Biogen PTY Ltd. Supply of interferon as 'Plegridy (peginterferon beta-1a).' The study was substantially funded by BHP Holdings Pty Ltd.
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Affiliation(s)
| | - Eleanor N. Fish
- Toronto General Hospital Research Institute, University Health Network & Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Samuel T. Montgomery
- Telethon Kids Institute, Perth, Australia
- School of Population Health, Curtin University, Bentley, Australia
| | | | - Carolina Iturriaga
- Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Casey Shannon
- Prevention of Organ Failure (PROOF) Centre of Excellence, Vancouver, British Columbia, Canada
| | | | - Joseph Ho
- Telethon Kids Institute, Perth, Australia
| | - Virginia Chen
- Prevention of Organ Failure (PROOF) Centre of Excellence, Vancouver, British Columbia, Canada
| | - Robert Balshaw
- Centre for Healthcare Innovation, University of Manitoba, Manitoba, Canada
| | | | | | | | | | | | | | - Marcela Urzúa
- Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Scott J. Tebbutt
- Prevention of Organ Failure (PROOF) Centre of Excellence, Vancouver, British Columbia, Canada
| | - Diego García-Huidobro
- Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Department of Family and Community Medicine, University of Minnesota, MN, USA
| | - Cecilia Perret
- Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Arturo Borzutzky
- Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Garcia-Huidobro D, Iturriaga C, Perez-Mateluna G, Fajuri P, Severino N, Urzúa M, Fraga JP, de la Cruz J, Poli C, Castro-Rodríguez JA, Fish E, Borzutzky A. Safety, Tolerability, Bioavailability, and Biological Activity of Inhaled Interferon-α2b in Healthy Adults: The IN 2COVID Phase I Randomized Trial. Clin Drug Investig 2023:10.1007/s40261-023-01278-3. [PMID: 37347370 DOI: 10.1007/s40261-023-01278-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2023] [Indexed: 06/23/2023]
Abstract
BACKGROUND AND OBJECTIVES Interferons have been identified as a potential treatment alternative for coronavirus disease 2019. This study assessed the safety, tolerability, bioavailability, and biological activity of inhaled interferon-α2b (IFN)-α2b in healthy adults. METHODS A double-blind, randomized, phase I clinical trial was conducted with two cohorts of healthy subjects aged 18-50 years. The first cohort received 2.5 MIU of inhaled IFN-α2b twice daily for 10 days (n = 6) or placebo (n = 3); the second cohort received 5.0 MIU of inhaled IFN-α2b in a similar scheme (n = 6) or placebo (n = 3). The first two doses were administered in an emergency department, then participants completed their treatment at home. Safety was measured through vital signs, new symptoms, and laboratory tests. Tolerability was measured as participants' treatment acceptability. Bioavailability and biological activity were measured from serum IFNα concentrations and real-time quantitative polymerase chain reaction of interferon-induced genes in blood before and after treatments. RESULTS Exposure to inhaled IFN-α2b at 2.5-MIU or 5-MIU doses did not produce statistically significant changes in participant vital signs, or elicit new symptoms, and standard hematological and biochemical blood measurements were comparable to those recorded in individuals who received placebo. A total of 58 adverse events were observed. All were mild or moderate and did not require medical care. All participants reported very high tolerability towards a twice-daily nebulized treatment for 10 days (98.0, 97.0, and 97.0 in the placebo, 2.5-MIU, and 5-MIU groups, respectively, on a 0- to 100-mm visual analog scale). A dose-dependent mild increase in serum IFN-α concentrations and an increase in serum RNA expression of IFN-induced genes were observed 11 days after treatment (p < 0.05 for all between-group comparisons). CONCLUSIONS Inhaled IFN-α2b was preliminarily safe and well tolerated, and induced systemic biological activity in healthy subjects. CLINICAL TRIAL REGISTRATION The trial was registered in ClinicalTrials.gov (NCT04988217), 3 August, 2021.
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Affiliation(s)
- Diego Garcia-Huidobro
- Department of Family Medicine, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- Department of Family Medicine and Community Health, University of Minnesota, Minneapolis, MN, USA
| | - Carolina Iturriaga
- Translational Allergy and Immunology Laboratory, Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Guillermo Perez-Mateluna
- Translational Allergy and Immunology Laboratory, Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Paula Fajuri
- Translational Allergy and Immunology Laboratory, Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás Severino
- Pharmacology and Toxicology ProgramSchool of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcela Urzúa
- Translational Allergy and Immunology Laboratory, Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Pablo Fraga
- Translational Allergy and Immunology Laboratory, Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Javiera de la Cruz
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Cecilia Poli
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - José A Castro-Rodríguez
- Department of Pediatric Pulmonology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Eleanor Fish
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Arturo Borzutzky
- Translational Allergy and Immunology Laboratory, Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
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Santander S, Padilla-Manzano N, Díaz B, Bacchiega R, Jara E, Álvarez LF, Pinto C, Forero JC, Santana P, Hamm E, Urzúa M, Tamayo L. Wettability of Amino Acid-Functionalized PSMA Electrospun Fibers for the Modulated Release of Active Agents and Its Effect on Their Bioactivity. Pharmaceutics 2023; 15:1659. [PMID: 37376107 DOI: 10.3390/pharmaceutics15061659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/25/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
The ideal treatment for chronic wounds is based on the use of bioactive dressings capable of releasing active agents. However, the control of the rate at which these active agents are released is still a challenge. Bioactive polymeric fiber mats of poly(styrene-co-maleic anhydride) [PSMA] functionalized with amino acids of different hydropathic indices and L-glutamine, L-phenylalanine and L-tyrosine levels allowed obtaining derivatives of the copolymers named PSMA@Gln, PSMA@Phe and PSMA@Tyr, respectively, with the aim of modulating the wettability of the mats. The bioactive characteristics of mats were obtained by the incorporation of the active agents Calendula officinalis (Cal) and silver nanoparticles (AgNPs). A higher wettability for PSMA@Gln was observed, which is in accordance with the hydropathic index value of the amino acid. However, the release of AgNPs was higher for PSMA and more controlled for functionalized PSMA (PSMAf), while the release curves of Cal did not show behavior related to the wettability of the mats due to the apolar character of the active agent. Finally, the differences in the wettability of the mats also affected their bioactivity, which was evaluated in bacterial cultures of Staphylococcus aureus ATCC 25923 and methicillin-resistant Staphylococcus aureus ATCC 33592, an NIH/3T3 fibroblast cell line and red blood cells.
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Affiliation(s)
- Sebastián Santander
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Nicolás Padilla-Manzano
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Bastián Díaz
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Renato Bacchiega
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Elizabeth Jara
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Luis Felipe Álvarez
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Cristóbal Pinto
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Juan C Forero
- Escuela de Ciencias de la Salud, Universidad de Viña del Mar, Viña del Mar 2572007, Chile
| | - Paula Santana
- Instituto de Ciencias Aplicadas, Facultad de Ingeniería, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, San Miguel, Santiago 8910060, Chile
| | - Eugenio Hamm
- Departamento de Física, Facultad de Ciencia, Universidad de Santiago de Chile, Av. Víctor Jara 3493, Estación Central, Santiago 9160000, Chile
| | - Marcela Urzúa
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
| | - Laura Tamayo
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago 7800003, Chile
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Maine A, Encinas MV, Pavez J, Urzúa M, Günther G, Reyes I, Briones X. On the Preparation of Thin Films of Stearyl Methacrylate Directly Photo-polymerized at the Air-Water Interface. Langmuir 2022; 38:11658-11665. [PMID: 36112511 DOI: 10.1021/acs.langmuir.2c01513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Characterization of bidimensional polymeric films at the air-water interface in the Langmuir trough, despite being a recurrent topic, usually refers to films of already formed polymeric materials, with very scarce reports on direct polymerization at the air-water interface. In the present work, we studied the photo-polymerization of stearyl methacrylate directly at the air-water interface under a nitrogen atmosphere, with the radical initiator solubilized in the aqueous phase. Two-dimensional (2D) polymerization was monitored by measuring the pressure-area isotherm at different irradiation times. The polymerization leads to a film with an isotherm different from that observed for the monomer, where the surface pressure is directly related to the irradiation time. The shape of this isotherm confirms the presence of a compressed liquid phase, where a higher order can be attained as a consequence of stronger packing forces involving polymer chains. The presence of inter-chain interactions allows rearrangements on the surface of the subphase, and even before the collapse a dense 2D ordering (with a solid phase-like behavior) can be observed. We present a new one-step, solvent-free procedure to obtain a photo-polymeric film directly at the air-water interface, which can be transferred to a solid surface by the Langmuir-Blodgett method, allowing film preparation of controlled thickness. Films were characterized by measuring properties such as thickness, roughness, and hydrophobicity and comparing them with films obtained from a conventional polymer. We report the differences between the interfacial behavior of amphiphilic molecules and nanomaterials such as films obtained by photo-polymerization, PSMA, directly on the air-water interface.
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Affiliation(s)
- A Maine
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Dr. Carlos Lorca Tobar 964, Independencia, Región Metropolitana, Casilla 233, Santiago, Chile
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago, Chile
| | - M V Encinas
- Facultad de Química y Biología, Universidad de Santiago de Chile, Av. B. O'Higgins 3363 Santiago, Chile
| | - J Pavez
- Departamento de Química de los Materiales, Facultad de Química y Biología, Soft Matter Research-Technology Center, SMAT-C, Universidad de Santiago de Chile, Av. B. O'Higgins 3363 Santiago, Chile
| | - M Urzúa
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago, Chile
| | - G Günther
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Dr. Carlos Lorca Tobar 964, Independencia, Región Metropolitana, Casilla 233, Santiago, Chile
| | - I Reyes
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Dr. Carlos Lorca Tobar 964, Independencia, Región Metropolitana, Casilla 233, Santiago, Chile
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago, Chile
| | - X Briones
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Dr. Carlos Lorca Tobar 964, Independencia, Región Metropolitana, Casilla 233, Santiago, Chile
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Ramírez O, Leal M, Briones X, Urzúa M, Bonardd S, Saldías C, Leiva A. New Hybrid Nanocomposites with Catalytic Properties Obtained by In Situ Preparation of Gold Nanoparticles on Poly (Ionic Liquid)/Poly (4-Vinylpyridine) Nanofibers. Polymers (Basel) 2022; 14:polym14183782. [PMID: 36145926 PMCID: PMC9504522 DOI: 10.3390/polym14183782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/02/2022] [Accepted: 09/07/2022] [Indexed: 11/16/2022] Open
Abstract
In this work, we report the obtaining of new hybrid nanocomposites with catalytic activity formed by nanofibers of polymer blends and gold nanoparticles. The nanofibers were obtained by electrospinning blends of a poly (ionic liquid) (PIL) and its precursor polymer, poly (4-vinyl pyridine) (P4VPy). The characteristics of the nanofibers obtained proved to be dependent on the proportion of polymer in the blends. The nanofibers obtained were used to synthesize, in situ, gold nanoparticles on their surface by two-step procedure. Firstly, the adsorption of precursor ions on the nanofibers and then their reduction with sodium borohydride to generate gold nanoparticles. The results indicated a significant improvement in the performance of PIL-containing nanofibers over pure P4VPy NFs during ion adsorption, reaching a 20% increase in the amount of adsorbed ions and a 6-fold increase in the respective adsorption constant. The catalytic performance of the obtained hybrid systems in the reduction reaction of 4-nitrophenol to 4-aminophenol was studied. Higher catalytic conversions were obtained using the hybrid nanofibers containing PIL and gold nanoparticles achieving a maximum conversion rate of 98%. Remarkably, the highest value of kinetic constant was obtained for the nanofibers with the highest PIL content.
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Affiliation(s)
- Oscar Ramírez
- Departamento de Físico Química, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Matías Leal
- Centro de Bioinformática y Biología Integrativa, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370035, Chile
| | - Ximena Briones
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 8380544, Chile
| | - Marcela Urzúa
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile
| | - Sebastián Bonardd
- Departamento de Química Orgánica, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 3, La Laguna, 38206 Tenerife, Spain
- Instituto de Bio-Orgánica Antonio González, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 2, La Laguna, 38206 Tenerife, Spain
| | - Cesar Saldías
- Departamento de Físico Química, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Angel Leiva
- Departamento de Físico Química, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
- Correspondence:
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Leal M, Leiva Á, Villalobos V, Palma V, Carrillo D, Edwards N, Maine A, Cauich-Rodriguez J, Tamayo L, Neira-Carrillo A, Urzúa M. Blends based on amino acid functionalized poly (ethylene-alt-maleic anhydride) polyelectrolytes and PEO for nanofiber elaboration:biocompatible and angiogenic polyelectrolytes. Eur Polym J 2022. [DOI: 10.1016/j.eurpolymj.2022.111269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Cordoba A, Saldias C, Urzúa M, Montalti M, Guernelli M, Focarete ML, Leiva A. On the Versatile Role of Electrospun Polymer Nanofibers as Photocatalytic Hybrid Materials Applied to Contaminated Water Remediation: A Brief Review. Nanomaterials 2022; 12:nano12050756. [PMID: 35269244 PMCID: PMC8912311 DOI: 10.3390/nano12050756] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/14/2022] [Accepted: 02/18/2022] [Indexed: 02/04/2023]
Abstract
A wide variety of materials, strategies, and methods have been proposed to face the challenge of wastewater pollution. The most innovative and promising approaches include the hybrid materials made of polymeric nanofibers and photocatalytic nanoparticles. Electrospun nanofibers with unique properties, such as nanosized diameter, large specific surface area, and high aspect ratio, represent promising materials to support and stabilize photocatalytic nanosized semiconductors. Additionally, the role performed by polymer nanofibers can be extended even further since they can act as an active medium for the in situ synthesis of photocatalytic metal nanoparticles or contribute to pollutant adsorption, facilitating their approach to the photocatalytic sites and their subsequent photodegradation. In this paper, we review the state of the art of electrospun polymer/semiconductor hybrid nanofibers possessing photocatalytic activity and used for the remediation of polluted water by light-driven processes (i.e., based on photocatalytic activity). The crucial role of polymer nanofibers and their versatility in these types of procedures are emphasized.
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Affiliation(s)
- Alexander Cordoba
- Department of Physical Chemistry, Faculty of Chemistry and Pharmacy, Pontifical Catholic University of Chile, Santiago 7820436, Chile; (A.C.); (C.S.)
- Department of Chemistry “Giacomo Ciamician” and National Consortium of Materials Science and Technology (I.N.S.T.M., Bologna RU), Alma Mater Studiorum–Università di Bologna, 40126 Bologna, Italy; (M.M.); (M.G.)
| | - Cesar Saldias
- Department of Physical Chemistry, Faculty of Chemistry and Pharmacy, Pontifical Catholic University of Chile, Santiago 7820436, Chile; (A.C.); (C.S.)
| | - Marcela Urzúa
- Department of Chemistry, Faculty of Sciences, University of Chile, Santiago 7820436, Chile;
| | - Marco Montalti
- Department of Chemistry “Giacomo Ciamician” and National Consortium of Materials Science and Technology (I.N.S.T.M., Bologna RU), Alma Mater Studiorum–Università di Bologna, 40126 Bologna, Italy; (M.M.); (M.G.)
| | - Moreno Guernelli
- Department of Chemistry “Giacomo Ciamician” and National Consortium of Materials Science and Technology (I.N.S.T.M., Bologna RU), Alma Mater Studiorum–Università di Bologna, 40126 Bologna, Italy; (M.M.); (M.G.)
| | - Maria Letizia Focarete
- Department of Chemistry “Giacomo Ciamician” and National Consortium of Materials Science and Technology (I.N.S.T.M., Bologna RU), Alma Mater Studiorum–Università di Bologna, 40126 Bologna, Italy; (M.M.); (M.G.)
- Health Sciences and Technologies-Interdepartmental Center for Industrial Research, Alma Mater Studiorum–Università di Bologna, 40126 Bologna, Italy
- Correspondence: (M.L.F.); (A.L.)
| | - Angel Leiva
- Department of Physical Chemistry, Faculty of Chemistry and Pharmacy, Pontifical Catholic University of Chile, Santiago 7820436, Chile; (A.C.); (C.S.)
- Correspondence: (M.L.F.); (A.L.)
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9
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Melo-González F, Soto JA, González LA, Fernández J, Duarte LF, Schultz BM, Gálvez NMS, Pacheco GA, Ríos M, Vázquez Y, Rivera-Pérez D, Moreno-Tapia D, Iturriaga C, Vallejos OP, Berríos-Rojas RV, Hoppe-Elsholz G, Urzúa M, Bruneau N, Fasce RA, Mora J, Grifoni A, Sette A, Weiskopf D, Zeng G, Meng W, González-Aramundiz JV, González PA, Abarca K, Ramírez E, Kalergis AM, Bueno SM. Recognition of Variants of Concern by Antibodies and T Cells Induced by a SARS-CoV-2 Inactivated Vaccine. Front Immunol 2021; 12:747830. [PMID: 34858404 PMCID: PMC8630786 DOI: 10.3389/fimmu.2021.747830] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/21/2021] [Indexed: 12/21/2022] Open
Abstract
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible of the current pandemic ongoing all around the world. Since its discovery in 2019, several circulating variants have emerged and some of them are associated with increased infections and death rate. Despite the genetic differences among these variants, vaccines approved for human use have shown a good immunogenic and protective response against them. In Chile, over 70% of the vaccinated population is immunized with CoronaVac, an inactivated SARS-CoV-2 vaccine. The immune response elicited by this vaccine has been described against the first SARS-CoV-2 strain isolated from Wuhan, China and the D614G strain (lineage B). To date, four SARS-CoV-2 variants of concern described have circulated worldwide. Here, we describe the neutralizing capacities of antibodies secreted by volunteers in the Chilean population immunized with CoronaVac against variants of concern Alpha (B.1.1.7), Beta (B.1.351) Gamma (P.1) and Delta (B.617.2). Methods Volunteers enrolled in a phase 3 clinical trial were vaccinated with two doses of CoronaVac in 0-14 or 0-28 immunization schedules. Sera samples were used to evaluate the capacity of antibodies induced by the vaccine to block the binding between Receptor Binding Domain (RBD) from variants of concern and the human ACE2 receptor by an in-house ELISA. Further, conventional microneutralization assays were used to test neutralization of SARS-CoV-2 infection. Moreover, interferon-γ-secreting T cells against Spike from variants of concern were evaluated in PBMCs from vaccinated subjects using ELISPOT. Results CoronaVac promotes the secretion of antibodies able to block the RBD of all the SARS-CoV-2 variants studied. Seropositivity rates of neutralizing antibodies in the population evaluated were over 97% for the lineage B strain, over 80% for Alpha and Gamma variants, over 75% for Delta variant and over 60% for the Beta variant. Geometric means titers of blocking antibodies were reduced when tested against SARS-CoV-2 variants as compared to ancestral strain. We also observed that antibodies from vaccinated subjects were able to neutralize the infection of variants D614G, Alpha, Gamma and Delta in a conventional microneutralization assay. Importantly, after SARS-CoV-2 infection, we observed that the blocking capacity of antibodies from vaccinated volunteers increased up to ten times for all the variants tested. We compared the number of interferon-γ-secreting T cells specific for SARS-CoV-2 Spike WT and variants of concern from vaccinated subjects and we did not detect significant differences. Conclusion Immunization with CoronaVac in either immunization schedule promotes the secretion of antibodies able to block SARS-CoV-2 variants of concern and partially neutralizes SARS-CoV-2 infection. In addition, it stimulates cellular responses against all variants of concern.
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Affiliation(s)
- Felipe Melo-González
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jorge A Soto
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Liliana A González
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jorge Fernández
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Luisa F Duarte
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Bárbara M Schultz
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás M S Gálvez
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gaspar A Pacheco
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mariana Ríos
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Yaneisi Vázquez
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela Rivera-Pérez
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela Moreno-Tapia
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Iturriaga
- Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Omar P Vallejos
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Roslye V Berríos-Rojas
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Guillermo Hoppe-Elsholz
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcela Urzúa
- Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicole Bruneau
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Rodrigo A Fasce
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Judith Mora
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Alba Grifoni
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology (LJI), La Jolla, CA, United States
| | - Alessandro Sette
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology (LJI), La Jolla, CA, United States.,Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego (UCSD), La Jolla, CA, United States
| | - Daniela Weiskopf
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology (LJI), La Jolla, CA, United States
| | | | | | - José V González-Aramundiz
- Departamento de Farmacia, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo A González
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Katia Abarca
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Eugenio Ramírez
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Alexis M Kalergis
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Endocrinología, Facultad de Medicina, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M Bueno
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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10
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Tamayo L, Santana P, Forero JC, Leal M, González N, Díaz M, Guiliani N, Hamm E, Urzúa M. Coaxial fibers of poly(styrene-co-maleic anhydride)@poly(vinyl alcohol) for wound dressing applications: Dual and sustained delivery of bioactive agents promoting fibroblast proliferation with reduced cell adherence. Int J Pharm 2021; 611:121292. [PMID: 34780927 DOI: 10.1016/j.ijpharm.2021.121292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/19/2022]
Abstract
The prevalence of chronic and acute wounds, as well as the complexity of their treatment represent a great challenge for health systems around the world. In this context, the development of bioactive wound dressings that release active agents to prevent infections and promote wound healing, appears as the most promising solution. In this work, we develop an antibacterial and biocompatible wound dressing material made from coaxial electrospun fibers of poly(styrene-co-maleic anhydride) and poly(vinyl alcohol) (PSMA@PVA). The coaxial configuration of the fibers consists of a shell of poly (styrene-co-maleic anhydride) containing a variable concentration of silver nanoparticles (AgNPs) 0.1-0.6 wt% as antibacterial agent, and a core of PVA containing 1 wt% allantoin as healing agent. The fibers present diameters between 0.72 and 1.7 µm. The release of Ag+ in a physiological medium was studied for 72 h, observing a burst release during the first 14 h and then a sustained and controlled release during the remaining 58 h. Allantoin release curves showed significant release only after 14 h. The meshes showed an antibacterial activity against Pseudomonas aeruginosa and Bacillus subtilis that correlates with the amount of AgNPs incorporated and the release rate of Ag+. Indeed, meshes containing 0.3 and 0.6 wt% of AgNPs showed a 99.99% inhibition against both bacteria. The adherence and cell viability of the meshes were evaluated in mouse embryonic fibroblasts NIH/3T3, observing a significant increase in cell viability after 72 h of incubation accompanied by a reduced adhesion of fibroblasts that decreased in the presence of the active agents. These results show that the material prepared here is capable of significantly promoting fibroblast cell proliferation but without strong adherence, which makes it an ideal material for wound dressings with non-adherent characteristics and with potential for wound healing.
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Affiliation(s)
- Laura Tamayo
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago, Chile
| | - Paula Santana
- Instituto de Ciencias Químicas Aplicadas, Facultad de Ingeniería, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, San Miguel, Santiago 8910060, Chile
| | - Juan C Forero
- Laboratorio de Química Biológica, Instituto de Química, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, 2340000, Chile
| | - Matías Leal
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago, Chile
| | - Nicolás González
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago, Chile
| | - Mauricio Díaz
- Laboratorio de Comunicación Bacteriana, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, P. C. 780-0023, Santiago, Chile
| | - Nicolás Guiliani
- Laboratorio de Comunicación Bacteriana, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, P. C. 780-0023, Santiago, Chile
| | - Eugenio Hamm
- Departamento Física, Facultad de Ciencia, Universidad de Santiago de Chile, av. Ecuador 3493, Estación Central, Santiago, Chile
| | - Marcela Urzúa
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago, Chile
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11
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Duarte LF, Gálvez NMS, Iturriaga C, Melo-González F, Soto JA, Schultz BM, Urzúa M, González LA, Vázquez Y, Ríos M, Berríos-Rojas RV, Rivera-Pérez D, Moreno-Tapia D, Pacheco GA, Vallejos OP, Hoppe-Elsholz G, Navarrete MS, Rojas Á, Fasce RA, Fernández J, Mora J, Ramírez E, Zeng G, Meng W, González-Aramundiz JV, González PA, Abarca K, Bueno SM, Kalergis AM. Immune Profile and Clinical Outcome of Breakthrough Cases After Vaccination With an Inactivated SARS-CoV-2 Vaccine. Front Immunol 2021; 12:742914. [PMID: 34659237 PMCID: PMC8511644 DOI: 10.3389/fimmu.2021.742914] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/06/2021] [Indexed: 01/14/2023] Open
Abstract
Constant efforts to prevent infections by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are actively carried out around the world. Several vaccines are currently approved for emergency use in the population, while ongoing studies continue to provide information on their safety and effectiveness. CoronaVac is an inactivated SARS-CoV-2 vaccine with a good safety and immunogenicity profile as seen in phase 1, 2, and 3 clinical trials around the world, with an effectiveness of 65.9% for symptomatic cases. Although vaccination reduces the risk of disease, infections can still occur during or after completion of the vaccination schedule (breakthrough cases). This report describes the clinical and immunological profile of vaccine breakthrough cases reported in a clinical trial in progress in Chile that is evaluating the safety, immunogenicity, and efficacy of two vaccination schedules of CoronaVac (clinicaltrials.gov NCT04651790). Out of the 2,263 fully vaccinated subjects, at end of June 2021, 45 have reported symptomatic SARS-CoV-2 infection 14 or more days after the second dose (1.99% of fully vaccinated subjects). Of the 45 breakthrough cases, 96% developed mild disease; one case developed a moderate disease; and one developed a severe disease and required mechanical ventilation. Both cases that developed moderate and severe disease were adults over 60 years old and presented comorbidities. The immune response before and after SARS-CoV-2 infection was analyzed in nine vaccine breakthrough cases, revealing that six of them exhibited circulating anti-S1-RBD IgG antibodies with neutralizing capacities after immunization, which showed a significant increase 2 and 4 weeks after symptoms onset. Two cases exhibited low circulating anti-S1-RBD IgG and almost non-existing neutralizing capacity after either vaccination or infection, although they developed a mild disease. An increase in the number of interferon-γ-secreting T cells specific for SARS-CoV-2 was detected 2 weeks after the second dose in seven cases and after symptoms onset. In conclusion, breakthrough cases were mostly mild and did not necessarily correlate with a lack of vaccine-induced immunity, suggesting that other factors, to be defined in future studies, could lead to symptomatic infection after vaccination with CoronaVac.
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Affiliation(s)
- Luisa F. Duarte
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás M. S. Gálvez
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Iturriaga
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Felipe Melo-González
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jorge A. Soto
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Bárbara M. Schultz
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcela Urzúa
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Liliana A. González
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Yaneisi Vázquez
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mariana Ríos
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Roslye V. Berríos-Rojas
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela Rivera-Pérez
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela Moreno-Tapia
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gaspar A. Pacheco
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Omar P. Vallejos
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Guillermo Hoppe-Elsholz
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - María S. Navarrete
- Departamento de Enfermedades Infecciosas del Adulto, División de Medicina, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Álvaro Rojas
- Departamento de Enfermedades Infecciosas del Adulto, División de Medicina, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo A. Fasce
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Jorge Fernández
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Judith Mora
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Eugenio Ramírez
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | | | | | - José V. González-Aramundiz
- Departamento de Farmacia, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo A. González
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Katia Abarca
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M. Bueno
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexis M. Kalergis
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Endocrinología, Facultad de Medicina, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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12
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Bueno SM, Abarca K, González PA, Gálvez NMS, Soto JA, Duarte LF, Schultz BM, Pacheco GA, González LA, Vázquez Y, Ríos M, Melo-González F, Rivera-Pérez D, Iturriaga C, Urzúa M, Domínguez A, Andrade CA, Berríos-Rojas RV, Canedo-Marroquín G, Covián C, Moreno-Tapia D, Saavedra F, Vallejos OP, Donato P, Espinoza P, Fuentes D, González M, Guzmán P, Muñoz Venturelli P, Pérez CM, Potin M, Rojas Á, Fasce RA, Fernández J, Mora J, Ramírez E, Gaete-Argel A, Oyarzún-Arrau A, Valiente-Echeverría F, Soto-Rifo R, Weiskopf D, Sette A, Zeng G, Meng W, González-Aramundiz JV, Kalergis AM. Safety and Immunogenicity of an Inactivated Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine in a Subgroup of Healthy Adults in Chile. Clin Infect Dis 2021; 75:e792-e804. [PMID: 34537835 PMCID: PMC9402626 DOI: 10.1093/cid/ciab823] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The development of effective vaccines against coronavirus disease 2019 is a global priority. CoronaVac is an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine with promising safety and immunogenicity profiles. This article reports safety and immunogenicity results obtained for healthy Chilean adults aged ≥18 years in a phase 3 clinical trial. METHODS Volunteers randomly received 2 doses of CoronaVac or placebo, separated by 2 weeks. A total of 434 volunteers were enrolled, 397 aged 18-59 years and 37 aged ≥60 years. Solicited and unsolicited adverse reactions were registered from all volunteers. Blood samples were obtained from a subset of volunteers and analyzed for humoral and cellular measures of immunogenicity. RESULTS The primary adverse reaction in the 434 volunteers was pain at the injection site, with a higher incidence in the vaccine than in the placebo arm. Adverse reactions observed were mostly mild and local. No severe adverse events were reported. The humoral evaluation was performed on 81 volunteers. Seroconversion rates for specific anti-S1-receptor binding domain (RBD) immunoglobulin G (IgG) were 82.22% and 84.44% in the 18-59 year age group and 62.69% and 70.37% in the ≥60 year age group, 2 and 4 weeks after the second dose, respectively. A significant increase in circulating neutralizing antibodies was detected 2 and 4 weeks after the second dose. The cellular evaluation was performed on 47 volunteers. We detected a significant induction of T-cell responses characterized by the secretion of interferon-γ (IFN-γ) upon stimulation with Mega Pools of peptides from SARS-CoV-2. CONCLUSIONS Immunization with CoronaVac in a 0-14 schedule in Chilean adults aged ≥18 years is safe, induces anti-S1-RBD IgG with neutralizing capacity, activates T cells, and promotes the secretion of IFN-γ upon stimulation with SARS-CoV-2 antigens.
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Affiliation(s)
| | - Katia Abarca
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo A González
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás M S Gálvez
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jorge A Soto
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luisa F Duarte
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Bárbara M Schultz
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gaspar A Pacheco
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Liliana A González
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Yaneisi Vázquez
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mariana Ríos
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Felipe Melo-González
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela Rivera-Pérez
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Iturriaga
- Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcela Urzúa
- Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Angélica Domínguez
- Departamento de Salud Pública, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Catalina A Andrade
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Roslye V Berríos-Rojas
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gisela Canedo-Marroquín
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Camila Covián
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela Moreno-Tapia
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Farides Saavedra
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Omar P Vallejos
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Paulina Donato
- Complejo Asistencial Dr. Sótero del Rio, Santiago, Chile
| | - Pilar Espinoza
- Hospital Clínico Félix Bulnes, Santiago, Chile,Facultad de Medicina y Ciencia y Facultad de Ciencias para el Cuidado de la Salud. Universidad San Sebastián, Santiago, Chile
| | - Daniela Fuentes
- Hospital Carlos Van Buren, V Región, Chile,Departamento de Pediatría, Universidad de Valparaíso, Valparaiso, Chile
| | - Marcela González
- Hospital Dr. Gustavo Fricke, V Región, Chile,Departamento de Pediatría, Universidad de Valparaíso, Valparaiso, Chile
| | - Paula Guzmán
- Clínica Los Andes, Universidad de Los Andes, Santiago, Chile
| | - Paula Muñoz Venturelli
- Centro de Estudios Clínicos, Instituto de Ciencias e Innovación en Medicina, Facultad de Medicina Clínica Alemana Universidad del Desarrollo, Santiago, Chile,The George Institute for Global Health, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Carlos M Pérez
- Hospital Clínico Félix Bulnes, Santiago, Chile,Facultad de Medicina y Ciencia y Facultad de Ciencias para el Cuidado de la Salud. Universidad San Sebastián, Santiago, Chile
| | - Marcela Potin
- Clínica San Carlos de Apoquindo, Red de Salud UC Christus, Santiago, Chile
| | - Álvaro Rojas
- Departamento de Enfermedades Infecciosas del Adulto, División de Medicina, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo A Fasce
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública deChile, Santiago, Chile
| | - Jorge Fernández
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública deChile, Santiago, Chile
| | - Judith Mora
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública deChile, Santiago, Chile
| | - Eugenio Ramírez
- Departamento de Laboratorio Biomédico, Instituto de Salud Pública deChile, Santiago, Chile
| | - Aracelly Gaete-Argel
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Aarón Oyarzún-Arrau
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Fernando Valiente-Echeverría
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Ricardo Soto-Rifo
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Daniela Weiskopf
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, California, USA
| | - Alessandro Sette
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, California, USA,Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego (UCSD), La Jolla, CA, USA
| | | | | | - José V González-Aramundiz
- Departamento de Farmacia, Facultad de Química y de Farmacia. Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexis M Kalergis
- Correspondence: A. M. Kalergis, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O’Higgins Nº 340, Santiago 8331010, Santiago, Chile ()
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13
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Cárdenas GV, Iturriaga C, Hernández CD, Tejos-Bravo M, Pérez-Mateluna G, Cabalin C, Urzúa M, Venegas-Salas LF, Fraga JP, Rebolledo B, Poli MC, Repetto GM, Casanello P, Castro-Rodríguez JA, Borzutzky A. Prevalence of filaggrin loss-of-function variants in Chilean population with and without atopic dermatitis. Int J Dermatol 2021; 61:310-315. [PMID: 34480753 DOI: 10.1111/ijd.15887] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 06/20/2021] [Accepted: 08/12/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND Filaggrin (FLG) loss-of-function variants are major genetic risk factors for atopic dermatitis (AD), but these have not been studied in Latin American populations with and without AD. METHODS FLG variants R501X and 2282del4 were genotyped in 275 Chilean adults with and without AD from the "Early origins of allergy and asthma" (ARIES) cohort and in 227 patients from an AD cohort based in Santiago, Chile. RESULTS Among adults in the ARIES cohort, 3.3% were carriers of R501X and 2.9% of 2282del4 variants, all heterozygotes. In this cohort, 6.2% were FLG variant carriers: 11.1% of subjects reporting AD were carriers of FLG variants vs. 5.2% in those without AD (P = 0.13). In this first cohort, FLG variants were not significantly associated with asthma, allergic rhinitis, or food allergy. In the AD cohort, the prevalence of FLG variants was 7% for R501X, 2.2% for the 2282del4 variant, and 9.3% for the combined genotype. In this cohort, FLG variants were present in 15.5% of severe AD vs. 7.1% of mild-to-moderate AD subjects (P = 0.056). Evaluation of Chilean population from both cohorts combined (n = 502) revealed that FLG variants were not significantly associated with AD (OR = 1.92 [95% CI 0.95-3.9], P = 0.067) but were associated with asthma (OR = 2.16 [95% CI 1.02-4.56], P = 0.039). CONCLUSIONS This is the first study to evaluate FLG loss-of-function variants R501X and 2282del4 in Latin American population, revealing a similar prevalence of these FLG variant carriers to that of European populations. Among Chileans, FLG variants were significantly associated with asthma but not AD.
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Affiliation(s)
- Geovanna V Cárdenas
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Iturriaga
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Caroll D Hernández
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Macarena Tejos-Bravo
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Guillermo Pérez-Mateluna
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Cabalin
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcela Urzúa
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luis F Venegas-Salas
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan P Fraga
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Boris Rebolledo
- Institute of Science and Innovation in Medicine, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Maria C Poli
- Institute of Science and Innovation in Medicine, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Gabriela M Repetto
- Institute of Science and Innovation in Medicine, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Paola Casanello
- Department of Neonatology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Obstetrics, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José A Castro-Rodríguez
- Department of Pediatric Pulmonology and Cardiology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Arturo Borzutzky
- Department of Pediatric Infectious Diseases and Immunology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
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14
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Bueno SM, Abarca K, González PA, Gálvez NM, Soto JA, Duarte LF, Schultz BM, Pacheco GA, González LA, Vázquez Y, Ríos M, Melo-González F, Rivera-Pérez D, Iturriaga C, Urzúa M, Dominguez A, Andrade CA, Berrios RV, Canedo-Marroquín G, Covián C, Moreno-Tapia D, Saavedra F, Vallejos OP, Donato P, Espinoza P, Fuentes D, González M, Guzmán P, Muñoz-Venturelli P, Pérez CM, Potin M, Rojas A, Fasce R, Fernández J, Mora J, Ramírez E, Gaete-Argel A, Oyarzún-Arrau A, Valiente-Echeverría F, Soto-Rifo R, Weiskopf D, Sette A, Zeng G, Meng W, González-Aramundiz JV, Kalergis AM. Interim report: Safety and immunogenicity of an inactivated vaccine against SARS-CoV-2 in healthy chilean adults in a phase 3 clinical trial. medRxiv 2021:2021.03.31.21254494. [PMID: 35441164 PMCID: PMC9016657 DOI: 10.1101/2021.03.31.21254494] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
BACKGROUND The ongoing COVID-19 pandemic has had a significant impact worldwide, with an incommensurable social and economic burden. The rapid development of safe and protective vaccines against this disease is a global priority. CoronaVac is a vaccine prototype based on inactivated SARS-CoV-2, which has shown promising safety and immunogenicity profiles in pre-clinical studies and phase 1/2 trials in China. To this day, four phase 3 clinical trials are ongoing with CoronaVac in Brazil, Indonesia, Turkey, and Chile. This article reports the safety and immunogenicity results obtained in a subgroup of participants aged 18 years and older enrolled in the phase 3 Clinical Trial held in Chile. METHODS This is a multicenter phase 3 clinical trial. Healthcare workers aged 18 years and older were randomly assigned to receive two doses of CoronaVac or placebo separated by two weeks (0-14). We report preliminary safety results obtained for a subset of 434 participants, and antibody and cell-mediated immunity results obtained in a subset of participants assigned to the immunogenicity arm. The primary and secondary aims of the study include the evaluation of safety parameters and immunogenicity against SARS-CoV-2 after immunization, respectively. This trial is registered at clinicaltrials.gov ( NCT04651790 ). FINDINGS The recruitment of participants occurred between November 27 th , 2020, until January 9 th , 2021. 434 participants were enrolled, 397 were 18-59 years old, and 37 were ≥60 years old. Of these, 270 were immunized with CoronaVac, and the remaining 164 participants were inoculated with the corresponding placebo. The primary adverse reaction was pain at the injection site, with a higher incidence in the vaccine arm (55.6%) than in the placebo arm (40.0%). Moreover, the incidence of pain at the injection site in the 18-59 years old group was 58.4% as compared to 32.0% in the ≥60 years old group. The seroconversion rate for specific anti-S1-RBD IgG was 47.8% for the 18-59 years old group 14 days post immunization (p.i.) and 95.6% 28 and 42 days p.i. For the ≥60 years old group, the seroconversion rate was 18.1%, 100%, and 87.5% at 14, 28, and 42 days p.i., respectively. Importantly, we observed a 95.7% seroconversion rate in neutralizing antibodies for the 18-59 years old group 28 and 42 days p.i. The ≥60 years old group exhibited seroconversion rates of 90.0% and 100% at 28 and 42 days p.i. Interestingly, we did not observe a significant seroconversion rate of anti-N-SARS-CoV-2 IgG for the 18-59 years old group. For the participants ≥60 years old, a modest rate of seroconversion at 42 days p.i. was observed (37.5%). We observed a significant induction of a T cell response characterized by the secretion of IFN-γ upon stimulation with Mega Pools of peptides derived from SARS-CoV-2 proteins. No significant differences between the two age groups were observed for cell-mediated immunity. INTERPRETATION Immunization with CoronaVac in a 0-14 schedule in adults of 18 years and older in the Chilean population is safe and induces specific IgG production against the S1-RBD with neutralizing capacity, as well as the activation of T cells secreting IFN-γ, upon recognition of SARS-CoV-2 antigens. FUNDING Ministry of Health of the Chilean Government; Confederation of Production and Commerce, Chile; Consortium of Universities for Vaccines and Therapies against COVID-19, Chile; Millennium Institute on Immunology and Immunotherapy.
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15
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Abarca K, Rey-Jurado E, Muñoz-Durango N, Vázquez Y, Soto JA, Gálvez NM, Valdés-Ferrada J, Iturriaga C, Urzúa M, Borzutzky A, Cerda J, Villarroel L, Madrid V, González PA, González-Aramundiz JV, Bueno SM, Kalergis AM. Safety and immunogenicity evaluation of recombinant BCG vaccine against respiratory syncytial virus in a randomized, double-blind, placebo-controlled phase I clinical trial. EClinicalMedicine 2020; 27:100517. [PMID: 33073219 PMCID: PMC7548429 DOI: 10.1016/j.eclinm.2020.100517] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/23/2020] [Accepted: 08/05/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Respiratory syncytial virus (RSV) is responsible for most respiratory tract infections and hospitalizations in infants and represents a significant economic burden for public health. The development of a safe, effective, and affordable vaccine is a priority for the WHO. METHODS We conducted a double-blinded, escalating-dose phase 1 clinical trial in healthy males aged 18-50 years to evaluate safety, tolerability, and immunogenicity of a recombinant Mycobacterium bovis BCG vaccine expressing the nucleoprotein of RSV (rBCG-N-hRSV). Once inclusion criteria were met, volunteers were enrolled in three cohorts in an open and successive design. Each cohort included six volunteers vaccinated with 5 × 103, 5 × 104, or 1 × 105 CFU, as well as two volunteers vaccinated with the full dose of the standard BCG vaccine. This clinical trial (clinicaltrials.gov NCT03213405) was conducted in Santiago, Chile. FINDINGS The rBCG-N-RSV vaccine was safe, well-tolerated, and no serious adverse events related to the vaccine were recorded. Serum IgG-antibodies directed against Mycobacterium and the N-protein of RSV increased after vaccination, which were capable of neutralizing RSV in vitro. Additionally, all volunteers displayed increased cellular response consisting of IFN-γ and IL-2 production against PPD and the N-protein, starting at day 14 and 30 post-vaccination respectively. INTERPRETATION The rBCG-N-hRSV vaccine had a good safety profile and induced specific cellular and humoral responses. FUNDING This work was supported by Millennium Institute on Immunology and Immunotherapy from Chile (P09/016), FONDECYT 1190830, and FONDEF D11E1098.
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Affiliation(s)
- Katia Abarca
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Corresponding authors at: Millennium Institute on Immunology and Immunotherapy. Pontificia Universidad Católica de Chile. Av. Libertador Bernardo O'Higgins No. 340, Santiago 8331010, Santiago, Chile.
| | - Emma Rey-Jurado
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Natalia Muñoz-Durango
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Endocrinología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Yaneisi Vázquez
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jorge A. Soto
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás M.S. Gálvez
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Javier Valdés-Ferrada
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Iturriaga
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcela Urzúa
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
| | - Arturo Borzutzky
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jaime Cerda
- Departamento de Salud Pública, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luis Villarroel
- Departamento de Salud Pública, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Victoria Madrid
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo A. González
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José V. González-Aramundiz
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Farmacia, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M. Bueno
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Corresponding authors at: Millennium Institute on Immunology and Immunotherapy. Pontificia Universidad Católica de Chile. Av. Libertador Bernardo O'Higgins No. 340, Santiago 8331010, Santiago, Chile.
| | - Alexis M. Kalergis
- Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Av. Libertador Bernardo O'Higgins No. 340, Santiago, Chile
- Departamento de Endocrinología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Corresponding authors at: Millennium Institute on Immunology and Immunotherapy. Pontificia Universidad Católica de Chile. Av. Libertador Bernardo O'Higgins No. 340, Santiago 8331010, Santiago, Chile.
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Calfumán K, Honores J, Isaacs M, Quezada D, Valdebenito J, Urzúa M. Quick and Easy Modification of Glassy Carbon Electrodes with Ionic Liquid and Tetraruthenated Porphyrins for the Electrochemical Determination of Atrazine in Water. ELECTROANAL 2019. [DOI: 10.1002/elan.201800771] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Karla Calfumán
- Núcleo de Química y Bioquímica, Facultad de Estudios InterdisciplinariosUniversidad Mayor Camino La Piramide #5750 Huechuraba Chile
| | - Jessica Honores
- Facultad de Química, Departamento de Química InorgánicaPontificia Universidad Católica de Chile Av. Vicuña Mackenna #4860 Macul Chile
| | - Mauricio Isaacs
- Facultad de Química, Departamento de Química InorgánicaPontificia Universidad Católica de Chile Av. Vicuña Mackenna #4860 Macul Chile
| | - Diego Quezada
- Facultad de Química y Biología, Departamento de Química de MaterialesUniversidad de Santiago de Chile Av. Libertador Bernardo O'Higgins #3363 Estacion Central Chile
| | - Javier Valdebenito
- Facultad de Ciencias, Departamento de QuímicaUniversidad de Chile Las Palmeras #3425 Ñuñoa Chile
| | - Marcela Urzúa
- Facultad de Ciencias, Departamento de QuímicaUniversidad de Chile Las Palmeras #3425 Ñuñoa Chile
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Tamayo L, Acuña D, Riveros AL, Kogan MJ, Azócar MI, Páez M, Leal M, Urzúa M, Cerda E. Porous Nanogold/Polyurethane Scaffolds with Improved Antibiofilm, Mechanical, and Thermal Properties and with Reduced Effects on Cell Viability: A Suitable Material for Soft Tissue Applications. ACS Appl Mater Interfaces 2018; 10:13361-13372. [PMID: 29627980 DOI: 10.1021/acsami.8b02347] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The use of implants carries on a series of problems, among them infections, poor biocompatibility, high levels of cytotoxicity, and significant mechanical differences between implants and host organs that promote stress shielding effects. These problems indicate that the materials used to make implants must meet essential requirements and high standards for implantations to be successful. In this work, we present the synthesis, characterization and evaluation of the antibiofilm, mechanical, and thermal properties, and cytotoxic effect of a nanocomposite-based scaffold on polyurethane (PU) and gold nanoparticles (AuNPs) for soft tissue applications. The effect of the quantity of AuNPs on the antibacterial activity of nanocomposite scaffolds was evaluated against Staphylococcus epidermidis and Klebsiella spp., with a resulting 99.99% inhibition of both bacteria using a small quantity of nanoparticles. Cytotoxicity was evaluated with the T10 1/2 test against fibroblast cells. The results demonstrated that porous nanogold/PU scaffolds have no toxic effects on fibroblast cells to the 5 day exposition. With respect to mechanical properties, stress-strain curves showed that the compressive modulus and yield strength of PU scaffolds were significantly enhanced by AuNPs (by at least 10 times). This is due to changes in the arrangement of hard segments of PU, which increase the stiffness of the polymer. Thermogravimetric analysis showed that the degradation onset temperature rises with an increase in the quantity of AuNPs. These properties and characteristics demonstrate that porous nanogold/PU scaffolds are suitable material for use in soft tissue implants.
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Affiliation(s)
- L Tamayo
- Facultad de Ingeniería, Instituto de Ciencias Químicas Aplicadas, Polymers and Macromolecules Center , Universidad Autónoma de Chile , El Llano Subercaseaux 2801 , San Miguel, Santiago 8910060 , Chile
- Departamento de Química, Facultad de Ciencias , Universidad de Chile , Las Palmeras 3425, Casilla 653 , Santiago 8320000 , Chile
| | - D Acuña
- Departamento de Física , Universidad de Santiago , Av. Ecuador 3493 , Santiago 8320000 , Chile
| | - A L Riveros
- Facultad de Ciencias Químicas y Farmacéuticas, Advanced Center for Chronic Diseases (ACCDiS) , Universidad de Chile , Santos Dumont 964, Casilla 233 , Santiago 8320000 , Chile
| | - M J Kogan
- Facultad de Ciencias Químicas y Farmacéuticas, Advanced Center for Chronic Diseases (ACCDiS) , Universidad de Chile , Santos Dumont 964, Casilla 233 , Santiago 8320000 , Chile
| | - M I Azócar
- Departamento de Química de los Materiales, Facultad de Química y Biología , Universidad de Santiago de Chile , Av. L. B. O'Higgins 3363, Casilla 40, Correo 33 , Santiago 8320000 , Chile
| | - M Páez
- Departamento de Química de los Materiales, Facultad de Química y Biología , Universidad de Santiago de Chile , Av. L. B. O'Higgins 3363, Casilla 40, Correo 33 , Santiago 8320000 , Chile
| | - M Leal
- Departamento de Química, Facultad de Ciencias , Universidad de Chile , Las Palmeras 3425, Casilla 653 , Santiago 8320000 , Chile
| | - M Urzúa
- Departamento de Química, Facultad de Ciencias , Universidad de Chile , Las Palmeras 3425, Casilla 653 , Santiago 8320000 , Chile
| | - E Cerda
- Departamento de Física , Universidad de Santiago , Av. Ecuador 3493 , Santiago 8320000 , Chile
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Leiva A, Fuentes I, Bossel E, Urzúa M, Méndez M, Pino M, Radić D, Márquez V, González-Nilo FD. Block copolymers in the synthesis of gold nanoparticles. Two new approaches: Copolymer aggregates as reductants and stabilizers and simultaneous formation of copolymer aggregates and gold nanoparticles. ACTA ACUST UNITED AC 2014. [DOI: 10.1002/pola.27354] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Angel Leiva
- Pontificia Universidad Católica de Chile, Facultad de Química, Departamento de Química Física; Santiago 7820436 Chile
| | - Irma Fuentes
- Pontificia Universidad Católica de Chile, Facultad de Química, Departamento de Química Física; Santiago 7820436 Chile
| | - Esteban Bossel
- Pontificia Universidad Católica de Chile, Facultad de Química, Departamento de Química Física; Santiago 7820436 Chile
| | - Marcela Urzúa
- Universidad de Chile, Facultad de Ciencias; Departamento de Química; Santiago 7800024 Chile
| | - Maximiliano Méndez
- Pontificia Universidad Católica de Chile, Facultad de Química, Departamento de Química Física; Santiago 7820436 Chile
| | - Maximiliano Pino
- Pontificia Universidad Católica de Chile, Facultad de Química, Departamento de Química Física; Santiago 7820436 Chile
| | - Deodato Radić
- Pontificia Universidad Católica de Chile, Facultad de Química, Departamento de Química Física; Santiago 7820436 Chile
| | - Valeria Márquez
- Universidad Andrés Bello, Facultad de Ciencias Biológicas, Centro de Bioinformática y Biología Integrativa; Santiago 8370146 Chile
| | - Fernando. D. González-Nilo
- Universidad Andrés Bello, Facultad de Ciencias Biológicas, Centro de Bioinformática y Biología Integrativa; Santiago 8370146 Chile
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Urzúa M, Leiva A, Espinoza-Beltrán FJ, Briones X, Saldías C, Pino M. Spontaneous adsorption of gold nanoparticles by polyelectrolyte thin films. J Nanosci Nanotechnol 2012; 12:8382-8390. [PMID: 23421219 DOI: 10.1166/jnn.2012.6669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Nanocomposed films constituted by gold nanoparticles immobilized onto polyelectrolytes were obtained and studied. To obtain the films, amino terminated silicon wafer surfaces were put in contact with aqueous solution of polyelectrolytes derived from Poly(maleic anhydride-alt-styrene) containing aryl and amine-alkyl groups in the side chains, in this condition the adsorption of macromolecules was achieved. The effects of the chemical nature of the side chains and ionic strength on the amounts of adsorbed polyelectrolytes were studied by ellipsometry. The adsorption of polyelectrolytes increases with increasing ionic strength in agreement with the screening-enhanced adsorption regime; the results are discussed considering the steric hindrance of the side chains and flexibility of the polymers. A spontaneous adsorption process of nanoparticles onto polyelectrolyte films took place when these last were immersed in a gold nanoparticles suspension. The adsorption amounts were qualitatively evaluated by SEM and AFM and these showed to be dependent on chemical structure of polyelectrolytes.
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Affiliation(s)
- Marcela Urzúa
- Facultad de Ciencias, Departamento de Química, Universidad de Chile, Casilla 653, Correo Central, Santiago, Chile
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Basha KA, Balakrishnan T, Urzúa M, Leiva A, Alegría L, Gargallo L, Radić D. Copolymers of Phenoxyethyl Methacrylate with Butyl Methacrylate: Synthesis, Characterization and Reactivity Ratios. INT J POLYM MATER PO 2009. [DOI: 10.1080/00914030802583759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Basha KA, Balakrishnan T, Urzúa M, Leiva A, Alegría L, Gargallo L, Radic D. Copolymers of Phenoxyethyl Methacrylate with Glycidyl Methacrylate: Synthesis, Characterization and Reactivity Ratios. INT J POLYM MATER PO 2008. [DOI: 10.1080/00914030701413306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Urzúa M, Gatica N, Gargallo L, Radić D. N-1-ALKYLITACONAMIC ACIDS-CO-STYRENE COPOLYMERS. 1. SYNTHESIS, CHARACTERIZATION AND MONOMER REACTIVITY RATIOS. Journal of Macromolecular Science, Part A 2007. [DOI: 10.1081/ma-100101079] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Basha KA, Balakrishnan T, Urzúa M, Leiva A, Gargallo L, Radic D. Copolymers of Phenoxyethyl Methacrylate with N‐Vinyl‐2‐pyrrolidone: Synthesis, Characterization and Reactivity Ratios. Journal of Macromolecular Science, Part A 2007. [DOI: 10.1080/10601320601044641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Leiva A, Urzúa M, Gargallo L, Radić D. Poly(ethylene oxide)s hydrophobically modified. Adsorption and spreading at the air–water interface. J Colloid Interface Sci 2006; 299:70-5. [PMID: 16527292 DOI: 10.1016/j.jcis.2006.01.063] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2005] [Revised: 01/16/2006] [Accepted: 01/29/2006] [Indexed: 10/24/2022]
Abstract
A comparative study of spread and adsorbed monolayer of poly(ethylene oxide)s of different molecular weight hydrophobically modified with alkyl isocyanates of different length chain is reported. The modification of the polymer was carried out according to reported procedures. The polymers obtained were studied at the air-water interface by Langmuir isotherms for spread monolayers and by Gibbs isotherms for the adsorption process. Isotherms obtained are interpreted in terms of the hydrophobic and hydrophilic balance of the polymers. Limiting area per repeating unit (A(0)) and collapse pressure (pi(c)) from spread monolayers were obtained. Spread monolayers of the hydrophobically modified polymers show larger collapse pressure values than unmodified polymer monolayers. In the adsorption process the excess surface concentration Gamma(infinity), area per repeat unit sigma, and efficiency of the adsorption were determined. The values of the area occupied per repeat unit in adsorbed monolayer (sigma) were larger than those of the spread monolayer. The efficiency of the adsorption of poly(ethylene oxide)s increases with the hydrophobic modification and with the alkyl chain length.
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Affiliation(s)
- Angel Leiva
- Departamento de Química Física, Facultad de Química, Pontificia Universidad, Católica de Chile, Casilla 302, Correo 22, Santiago, Chile.
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Urzúa M, Sandoval C, González-Nilo F, Leiva A, Gargallo L, Radić D. Blends containing amphiphilic polymers. V. Compatibilization ofN-alkylitaconamic acid-co-styrene copolymers with interacting polymers. J Appl Polym Sci 2006. [DOI: 10.1002/app.24652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Gargallo L, Leiva A, Urzúa M, Alegría L, Miranda B, Radić D. Modification of the air–water interface by a chitosan adsorption process. Effect on an amphiphilic polymer monolayer. POLYM INT 2004. [DOI: 10.1002/pi.1474] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
The effect of phenols containing different electron-withdrawing substituents on the potentiometric responses of several liquid PVC membranes containing the complex trioctylmethylammonium-nitrate, TOMA(+)NO(3)(-), is analyzed. The results make it possible to separate these phenols into two groups; those phenols containing electron-releasing groups, which produce almost Nernstian slopes, and those containing electron-withdrawing substituents, which generate sub-Nernstian slopes. The highly negative standard free energy of transfer of the aryl phenolic group from water to a cationic polar head suggests that these phenols are mainly located in the membrane phase associated with TOMA(+) via a cation-pi interaction. It seems that the strength of this interaction, and hence of the nitrate dissociation, is affected by the presence of phenols in an extension which correlates well with the kind of phenol present in these membranes and, consequently, with the type of their potentiometric responses.
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Affiliation(s)
- Walton J Cabrera
- Departamento de Química, Universidad Arturo Prat, Casilla 121, Iquique, Chile
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Miranda B, Gargallo L, Urzúa M, Leiva A, González-Nilo F, Radić D. N-1-alkylitaconamic acids-co-styrene copolymers. Surface characterization. POLYMER 2003. [DOI: 10.1016/s0032-3861(03)00319-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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