Bibiana Vallejo

Dr. Bibiana Vallejo


Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 May 2019 in Sensors
Verified
Journal Article
Open access
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AHAura Hernández
Aura Hernández
BVBibiana Vallejo
Bibiana Vallejo
TRTautgirdas Ruzgas
Tautgirdas Ruzgas
SBSebastian Björklund
Sebastian Björklund
Sunlight is vital for several biochemical processes of the skin organ. However, acute or chronic exposure to ultraviolet radiation (UVR) has several harmful effects on the skin structure and function, especially in the case of the failing function of antioxidative enzymes, which may lead to substantial tissue damage due to the increased presence of reactive oxygen species (ROS). The aim of this work was to investigate the combined effect of ultraviolet B (UVB) irradiation and oxidative stress on the skin barrier integrity. For this, we employed electrical impedance spectroscopy (EIS) to characterize changes of the electrical properties of excised pig skin membranes after various exposure conditions of UVB irradiation, oxidative stress, and the inhibition of antioxidative enzymatic processes. The oxidative stress was regulated by adding hydrogen peroxide (H2O2) as a source of ROS, while sodium azide (NaN3) was used as an inhibitor of the antioxidative enzyme catalase, which is naturally present throughout the epidermis. By screening for the combined effect of UVB and oxidative stress on the skin membrane electrical properties, we developed a new protocol for evaluating these parameters in a simple in vitro setup. Strikingly, the results show that exposure to extreme UVB irradiation does not affect the skin membrane resistance, implying that the skin barrier remains macroscopically intact. Likewise, exposure to only oxidative stress conditions, without UVB irradiation, does not affect the skin membrane resistance. In contrast to these observations, the combination of UVB irradiation and oxidative stress conditions results in a drastic decrease of the skin membrane resistance, indicating that the integrity of the skin barrier is compromised. Further, the skin membrane effective capacitance remained more or less unaffected by UVB exposure, irrespective of simultaneous exposure of oxidative stress. The EIS results were concluded to be associated with clear signs of macroscopic tissue damage of the epidermis as visualized with microscopy after exposure to UVB irradiation under oxidative stress conditions. Finally, the novel methodology was tested by performing an assessment of cosmetic sunscreen formulations with varying sun protection factor (SPF), with an overall successful outcome, showing good correlation between SPF value and protection capacity in terms of skin resistance change. The results from this study allow for the development of new skin sensors based on EIS for the detection of skin tissue damage from exposure to UVB irradiation and oxidative stress and provide a new, more comprehensive methodology, taking into account both the influence of UVB irradiation and oxidative stress, for in vitro determination of SPF in cosmetic formulations.

26 October 2016 in Pharmaceutical Research
Verified
Journal Article
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ARAnurag S. Rathore
Anurag S. Rathore
OGOscar Fabián Garcia-Aponte
Oscar Fabián Garcia-Aponte
AGAydin Golabgir
Aydin Golabgir
BVBibiana Vallejo
Bibiana Vallejo
Christoph HerwigChristoph Herwig
Christoph Herwig
Knowledge Management (KM) is a key enabler for achieving quality in a lifecycle approach for production of biopharmaceuticals. Due to the important role that it plays towards successful implementation of Quality by Design (QbD), an analysis of KM solutions is needed. This work provides a comprehensive review of the interface between KM and QbD-driven biopharmaceutical production systems as perceived by academic as well as industrial viewpoints. A comprehensive set of 356 publications addressing the applications of KM tools to QbD-related tasks were screened and a query to gather industrial inputs from 17 major biopharmaceutical organizations was performed. Three KM tool classes were identified as having high relevance for biopharmaceutical production systems and have been further explored: knowledge indicators, ontologies, and process modeling. A proposed categorization of 16 distinct KM tool classes allowed for the identification of holistic technologies supporting QbD. In addition, the classification allowed for addressing the disparity between industrial and academic expectations regarding the application of KM methodologies. This is a first of a kind attempt and thus we think that this paper would be of considerable interest to those in academia and industry that are engaged in accelerating development and commercialization of biopharmaceuticals.

27 November 2023 in Pharmaceutics
Verified
Journal Article
Open access
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LNLuis Eduardo Mosquera Narvaez
Luis Eduardo Mosquera Narvaez
MCMarcela Carrillo
Marcela Carrillo
JJJuliana Erika Cristina Cardona Jaramillo
Juliana Erika Cristina Cardona Jaramillo
BVBibiana Vallejo
Bibiana Vallejo
LFLindalva Maria de Meneses Costa Ferreira
Lindalva Maria de Meneses Costa Ferreira
RCRoseane Maria Ribeiro Costa
Roseane Maria Ribeiro Costa
Organogels have importance for topical applications because they can be used to deliver drugs in a controlled and prolonged fashion. These are materials consisting of a three-dimensional network of organic molecules dispersed in a solvent. Recent studies have demonstrated that the solvent could be replaced by oils from non-conventional biologic sources. There is a diversity of not-explored species in the Amazon that are promising sources of vegetable oils with a promising composition. This study developed an organogel with buriti (Mauritia flexuosa L.f) and cacay (Caryodendron orinocense Karst.) oils, using cetostearyl alcohol as an organogelator due to its compatibility, stability, security, affordability, and it is readily available. The oils were characterized, and the organogels were synthesized by studying their crystal evolution and oil-binding capacity. The microstructure was evaluated with polarized light microscopy, fractal dimension, FTIR spectroscopy, XRD, and thermal and rheological analyses. It was found that the critical gelation concentration was higher for cacay oil as it possessed a higher amount of polyunsaturated triacylglycerols. The crystals of the buriti organogel had a smaller lamellar shape, a greater surface area, and physical and thermal stability; although, it presented a slower crystal evolution due to the low number of minor compounds and a greater number of saturated triacylglycerols. The polar fraction of the organogelators as well as triacylglycerol and minor polar compounds are important in forming crystallization nuclei. The study showed that Amazonian oils in crystallization processes form microstructures with differentiating physicochemical properties.

1 July 2019 in Journal of Controlled Release
Verified
Journal Article
Closed access
AHAura Rocio Hernández
Aura Rocio Hernández
MBMarine Boutonnet
Marine Boutonnet
BSBirgitta Svensson
Birgitta Svensson
EBEile Butler
Eile Butler
RLRolf Lood
Rolf Lood
SBSebastian Björklund
Sebastian Björklund

25 February 2013 in Immunopharmacology and Immunotoxicology
Verified
Journal Article
Closed access
JGJennifer Gutiérrez
Jennifer Gutiérrez
BVBibiana Vallejo
Bibiana Vallejo
HBHelber Barbosa
Helber Barbosa
JPJohn Pinzón
John Pinzón
GDGabriela Delgado
Gabriela Delgado
Owing to its biocompatibility properties and its ability to promote the scar healing process, chitosan is employed in tissue engineering for the manufacture of formulations. To control the characteristic skin ulcers of cutaneous leishmaniasis (CL), the use of a biopolymeric system that favors the scar healing process and releases an active agent such as meglumine antimoniate may be a better option. For these reasons, here we analyzed the cytotoxic capabilities of excipients [medium molecular weight chitosan (MMWC), lactic acid (LA) and polyvinylpyrrolidone (PVP)], used for the formulation of a film-based therapeutic system that releases meglumine antimoniate and were evaluated on human macrophages [monocyte-derived macrophages (MDMs)], L929 fibroblasts and parasites (Leishmania major promastigotes and intracellular amastigotes). The ability of excipients to modulate the cytokines production involved in the scar healing process was compared with film-based therapeutic system. The efficiency of a film-based therapeutic system loaded with meglumine antimoniate was compared with conventional formulation (Albiventriz®). We found that MMWC was toxic for two parasite forms. In contrast, measurement of interleukin levels did not show any evidence of preferential secretion as a side effect of treating human macrophages with MMWC. Finally, the efficiency of a polymeric film-based therapeutic system that was loaded with meglumine antimoniate could not be determined due to the high degree of toxicity observed in infected MDMs; moreover, these compounds do not induce any apparent immunomodulatory effects. Our findings suggest that the final concentrations of each excipients (MMWC, LA and PVP) that were used in the polymeric film were suitable vehicles for active pharmaceutical compound delivery and did not selectively affect (enhancing or diminishing immune activity) macrophages.

1 January 2010 in Ingeniería e Investigación
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Journal Article
Open access
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JCJohn Jairo Gallo Castro
John Jairo Gallo Castro
BVBibiana Vallejo
Bibiana Vallejo
CBClara Eugenia Plazas Bonilla
Clara Eugenia Plazas Bonilla
The pharmaceutical industrial has five subsectors: medicines, cosmetics, phytotherapeutics, cleaning products and medical devices. The medicine subsector consists of organisations producing, importing and selling these products. Most studies about this industry have been guided by economic interests without assessing technological aspects of production. This article was aimed at proposing a methodology for assessing and describing the medicine sector according to its technological development by using the manufacturing capability concept. The main information was taken from the Colombian Medicaments and Food Surveillance Institutes (Instituto Nacional de Vigilancia de Medicamentos y Alimentos - INVIMA) databases related to pharmaceutical plant production in Bogotá, including material transformation facilities. This study led to three characteristics being identified for defining the pharmaceutical industrys manufacturing capability: that related to the pharmacological group to which active pharmaceutical ingredients belong, that linked to specifications regarding medicines sterility and that related to the technology required for manufacturing each pharmaceutical product. An analysis of these features has thus been presented and some technologies have been identified which have not been transferred or assimilated by the organisations being studied. It was found that manufacturing capability should be considered as being an indicator of the degree of technological development in these subsectors in Colombia.