Química
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Item Evaluación de Actividad Antidiabética in vitro del extracto peptídico obtenido a partir de la hidrólisis enzimática de la proteína quinua(Universidad Santiago de Cali, 2025-12-02) Taborda Trujillo, Juan Sebastián; Oñate Garzón, José Fernando (Director); Ciro Monsalve, Yhors Alexander (Director)Diabetes mellitus comprises two main forms: type 1 (DM1), of autoimmune origin with destruction of pancreatic βcells, and type 2 (DM2), associated with insulin resistance and chronic hyperglycemia, both representing a growing public health challenge due to their cardiovascular, renal, and neurological complications. Among nonpharmacological strategies, α-glucosidase inhibitors stand out for their ability to modulate intestinal carbohydrate absorption. Several studies have reported that protein hydrolysates from plant sources generate bioactive peptides capable of inhibiting this enzyme and contributing to the control of postprandial glycemia, supporting the interest in quinoa (Chenopodium quinoa Willd.), an Andean pseudocereal of high nutritional value. In this study, quinoa protein hydrolysates were obtained using actinidin, a cysteine protease extracted from kiwi (Actinidia deliciosa). The purified enzyme (~23 kDa) reached 3657 µg/mL, and hydrolysis produced an extract of 839 µg/mL with a degree of hydrolysis of 12.3%. The hydrolysate inhibited α-glucosidase by 29.4% at 122 µg/mL. Molecular docking identified the peptide DTVFADK (-8.921 kcal/mol) as the lowest binding energy among 10 candidate peptides (<10 AA), obtained through specific cleavage at the C-terminal of lysine residues from globulin 11S and albumin 2S, showing interactions comparable to acarbose. These findings support quinoa as a potential source of antidiabetic peptides for complementary diabetes management.Item Identificación de residuos de plaguicidas en frutas y verduras por cromatografía gaseosa y cromatografía líquida de alta resolución acoplada a espectrometría de masas: Revisión sistemática(Universidad Santiago de Cali, 2025-12-09) Mendoza Yarce, Mauricio; Mosquera González, Sergio David (Director)This study aimed to synthesize scientific evidence on the identification of pesticide residues in fruits and vegetables using advanced chromatographic techniques, specifically gas chromatography (GC) and high-performance liquid chromatography (HPLC) coupled with mass spectrometry. A systematic review was conducted across databases including Scopus, ScienceDirect, PubMed, and Taylor & Francis, considering publications in English and Spanish from 2005 to 2025. Approximately 236,488 records were retrieved from the databases consulted. After applying the PRISMA methodology, 200 potentially relevant studies were identified. Following the initial screening, 71 studies remained after excluding those that did not meet criteria related to title, abstract, chromatographic methodology, or extraction technique. During the eligibility stage, the set was reduced to 20 studies, selected after a full-text review to confirm inclusion of validation parameters. Finally, at the inclusion stage, 4 studies were selected. These studies featured complete validation, matrix effect control, and detection of multiple pesticide families, including organophosphates, organochlorines, carbamates, and benzimidazoles. The evidence indicated that sample preparation methods based on QuEChERS, combined with GC-MS/MS and LC-HRMS, were the most widely employed due to their high sensitivity, reproducibility, and ability to handle complex matrices. Differences were also observed in quantification limits and in international regulatory frameworks regarding maximum residue limits (MRLs). It was concluded that chromatographic techniques coupled with mass spectrometry constitute essential tools for monitoring pesticide residues in horticultural products. The findings underscore the need to harmonize regulatory frameworks and strengthen monitoring programs to ensure food safety and protect public health.Item Métodos cromatográficos aplicados al análisis de residuos de antibióticos en productos de origen animal: una revisión(2025-11-18) Gañan Sanchez, Elcy Johana; Castro Narváez, Sandra Patricia (Directora)The presence of different antibiotic residues in foods of animal origin represents a growing problem, affecting food safety and significantly contributing to the development of antimicrobial resistance. In this systematic review, several chromatographic methods applied to the detection and quantification of antibiotic residues in animalderived matrices were analyzed. For this purpose, published studies were compiled and examined, including various families of antibiotics and several types of matrices, such as milk, meat, liver, eggs, and aquatic products, with the aim of identifying methodological trends, strengths, and limitations of the techniques employed. The analyses of these studies showed that the most frequently investigated antibiotics were β-lactams, tetracyclines, aminoglycosides, macrolides, sulfonamides, and quinolones, whose physicochemical properties influenced sample preparation and detection efficiency. It was found that, although HPLC remains the most widely used technique due to its low cost, it has limited sensitivity when applied to complex matrices. In contrast, UHPLCMS/MS and LC-MS/MS allowed the detection of smaller amounts of residues, in the µg/kg range, with recoveries between 80 and 110%. Studies that reported validations demonstrated general compliance with international regulations, although gaps were identified in the evaluation of stability and matrix effects. Chromatographic methods are essential to ensure food safety and to control antimicrobial resistance; however, more harmonized protocols and new methodologies that are rapid, sustainable, and cost-effective are still needed.Item Obtención de biopelículas de almidón de yuca mejoradas con óxido de titanio e indicadores naturales(Universidad Santiago de Cali, 2025-12-03) Camacho Piedrahita, Alexis; Vivas Arango, Nicolas; Castro Narváez, Sandra Patricia (Directora)The increase in petroleum-based plastic waste is causing an environmental pollution crisis that affects aquatic and terrestrial ecosystems, making it necessary to search for new economical, safe, and sustainable alternatives for bag-type packaging applications that reduce the carbon footprint. This work presents the development of cassava starch bioplastics reinforced with titanium dioxide, cellulosic polymers, and plasticizers, incorporating anthocyanins and curcumin as pH indicators. They were produced by casting and characterized by mechanical testing, FTIR with KBr and HATR, and thermal analysis (DSC/TGA). The results showed an increase in tensile strength from 7.0N/cm² (PC3) to 17.0 N/cm² (2A), a value close to that of high-density polyethylene (20–30 N/cm²). Water absorption varied between 7.52% and 24.8%, compared to <0.01% for HDPE, confirming the hydrophilic nature of starch. The FTIR spectra showed polysaccharide bands (O–H 3400 cm⁻¹, C–O–C 1020 cm⁻¹) and Ti–O signals (500–700cm⁻¹), confirming the incorporation of TiO₂.Thermal analyses showed stability up to 200 °C and degradation between 201–334 °C. Finally, the films showed color changes from pH 1 to 13, validating their application in smart active packaging.Item Review: Evaluación de NIRS como método de identificación eficiente de microplásticos(Universidad Santiago de Cali, 2025-11-18) Quintero Zorrilla, Valentina; Ríos Acevedo, Jhon Jairo (Director)Growing concern about microplastic contamination has driven the search for reliable analytical methods capable of identifying and quantifying these particles in environmental and biological matrices. Faced with this challenge, near-infrared spectroscopy (NIRS) and its hyperspectral modality (NIR-HSI) have emerged as emerging rapid, nondestructive, and relatively low-cost screening techniques, giving them operational advantages over established methodologies such as FTIR, Raman, and Py-GC/MS. This research, developed using a qualitative approach and following the PRISMA systematic review guidelines, critically analyzed the efficiency, limitations, and projections of NIRS in the identification of microplastics. The review covered scientific literature published between 2010 and 2025, with an emphasis on validated experimental studies in environmental matrices (water, soil, air, sediments, and biota), as well as in industrial and recycling applications. The findings indicate that NIRS achieves identification rates above 90% for common polymers such as PE, PP, PET, PS, and PVC, especially for particles larger than 100 µm, highlighting its potential for mass monitoring and in situ applications. However, the technique has significant limitations: lower sensitivity for small particles or nanoplastics, interferences generated by water, biofilms, and mineral fillers, and the lack of standardized protocols and representative spectral libraries of degraded polymers. These restrictions limit its adoption as a single reference method but reinforce its value as a complementary tool within integrated workflows.Item Detección de benzodiacepinas y sus metabolitos en muestras biológicas: una perspectiva desde la toxicología forense. Revisión sistemática(Universidad Santiago de Cali, 2025-12-13) Chiran Chuquizan, Alexis Adelmo; Ocampo Chaguendo, Dennis Mauricio (Director)The identification of benzodiazepines and their metabolites in forensic toxicology requires the use of highly sensitive and specific instrumental techniques. In that order, the objective of this work was to comparatively analyze the main methodologies used for the detection and identification of benzodiazepines in biological samples, evaluating their efficiency, applicability in forensic contexts and differences according to the type of matrix. This was done from a documentary review of recent scientific sources, which focused on techniques such as immunoassays, gas chromatography (GC-MS) and liquid chromatography coupled to mass spectrometry (LCMS/MS and LC-HRMS). In addition, different biological matrices (blood, urine, oral fluid, hair, tissues) were compared and the strengths and limitations of each method in the forensic field were analyzed. It can be stated that instrumental techniques using LC-MS/MS are the most effective for the detection of benzodiazepines in the context of forensic toxicology, given their high sensitivity and the fact that they allow the detection of multiple compounds. The standard matrix remains blood, although matrices such as bile, vitreous humor, hair, and dried samples become quite important in postmortem cases. The methodological choice will involve adaptation to the case, based on sample availability, the detection window, and the forensic context itself.Item Composición volátil de la pulpa de zapote en diferentes estados de maduración(Universidad Santiago de Cali, 2025-12-10) Calderón Herrera, Santiago; Castro Narváez, Sandra Patricia (Directora); Suarez Osorio, Liseth (Directora)This study evaluated the physicochemical and chromatographic changes associated with the ripening process of Matisia cordata (zapote) fruit. Five maturity stages were analyzed through the determination of drying loss, soluble solids, titratable acidity, pH, organoleptic profile, and volatile composition by GC-MS (HS-SPME). The results showed a progressive increase in °Brix and pH, accompanied by a decrease in acidity, reflecting the conversion of starches into sugars and the degradation of organic acids. Chromatographic analysis revealed volatile compounds characteristic of each stage, with a predominance of aldehydes in green fruits and esters and acids in ripe ones. It is concluded that the mature stage represents the optimal point of sensory quality and metabolic balance of the fruit. These findings contribute to the biochemical understanding of zapote and its potential for industrial utilization.Item Tendencias de la espectroscopia infrarrojo cercano (NIRS) en el estudio de hidrocarburos aromáticos policíclicos (HAPs) en diferentes matrices(Universidad Santiago de Cali, 2025-11-24) Cuellar Ramirez, Juan Felipe; Castro Narváez, Sandra Patricia (Directora)Growing concern about environmental and food contamination by polycyclic aromatic hydrocarbons (PAHs), highly carcinogenic compounds that are currently detected using costly and time-consuming chromatography, calls for the development of faster and more sustainable analytical methods. This article presents a systematic review that evaluated and consolidated the applications of near-infrared spectroscopy (NIRS) and chemometrics for the rapid, non-destructive, and accurate detection, quantification, and characterization of PAHs. The review focused on 38 scientific articles published between 2018 and 2025 and indexed in key databases (Elsevier, Cell Press, ScienceDirect, Scopus) and search engines such as Google Scholar and Scielo. The findings confirm the versatility of NIRS with applications ranging from monitoring soils and waters contaminated by oil extraction and the development of photocatalysts to studying the presence of PAHs in astronomical objects such as the galaxy NGC 2782. Ultimately, the review validates the potential of NIRS for the development of low-cost portable sensors, representing a crucial advance for efficient environmental monitoring and food safety.Item Espectroscopia en el infrarrojo cercano: un review de las aplicaciones en el control de la calidad en el proceso industrial de la caña de azúcar(Universidad Santiago de Cali, 2025-12-05) Davalos Sierra, Joan Sebastian; Orduña Ortega, Julieth (Directora); Mora Vargas, Jorge Andrés (Director)The sugar industry, a key economic pillar in many tropical countries such as Colombia, requires the adoption of rapid, sustainable, and efficient analytical methods for quality control of sugarcane from cultivation to processing in biorefineries. Conventional methods, although effective, are often slow, costly, and environmentally unfavorable. In this context, near-infrared spectroscopy (NIRS) emerges as a promising alternative, capable of accurately quantifying key parameters such as °Brix and fiber content, achieving coefficients of determination (R²) above 0.97, while also enabling the characterization of cane and bagasse composition. Its effectiveness lies in correlating spectral data with chemical properties through calibrated chemometric models, making NIRS a versatile, reliable, and essential tool for enhancing the optimization and sustainability of the sugar agroindustry.Item Identificación de las líneas rotacionales de los isómeros del glicolaldehído en el objeto protoestelar IRAS 4A, en la nube molecular de Perseo(Universidad Santiago de Cali, 2025-12-11) Rivera Luna, Carlos Andrés ; Quitian Lara, Heidy Mayerly (Director); Pelegrín Ramírez, Jonathan (Director)The observation and identification of molecules in interstellar systems has applications in understanding interstellar chemical evolution, demonstrating that these systems are not only composed of dust and gases, but also contain a variety of chemical compounds, both complex and simple. In this research, the rotational lines of glycolaldehyde and its isomers, methyl formate and acetic acid, were identified and analyzed in the solar type protostellar object IRAS4A, located in the Perseus molecular cloud. Using Cassis software, the 1-, 2-, and 3-mm spectral bands were processed under local thermal equilibrium (LTE) conditions. The rotational diagrams allowed temperatures of 27.7 K for acetic acid, 55.5 K for glycolaldehyde, and two components (43.2 K and 86.6 K) for methyl formate to be obtained, evidencing the coexistence of different thermal regions in the system. The relative abundances indicate that methyl formate is the most abundant species.Item Eliminación de trihalometanos en aguas potables por medio de procesos de oxidación avanzada. Revisión sistemática(Universidad Santiago de Cali, 2025-12-02) Biojó Carvajal, Evelyn Omara; Ríos Acevedo, John Jairo (Director)The presence of disinfection by-products such as trihalomethanes (THMs) in drinking water poses a public health risk due to their toxicity. Therefore, disinfection methods are of vital importance in water treatment. However, it has been demonstrated that conventional techniques are not fully effective in reducing emerging contaminants such asTHMs. This has driven the scientific community to develop and innovate alternative approaches, such as advanced oxidation processes (AOPs), which are characterized by their high oxidative power and ability to degrade persistent organic contaminants through the generation of hydroxyl radicals. In this systematic review, studies published between 2019 and 2025 in indexed databases on the removal of THMs and their precursors were compiled and analyzed, considering inclusion and exclusion criteria that helped reduce bias in the literature search. The results show that, although processes such as Fenton and photocatalysis represent promising alternatives for precursor and THM degradation, their efficiency strongly depends on water composition, the characteristics of the precursors present, and the doses applied.Item Revisión sistemática sobre estrategias de mejora en la gestión documental en laboratorios de análisis fisicoquímico de aguas crudas en PYMEs bajo los lineamientos de las normas ISO 9001:2015 e ISO/IEC 17025:2017(Universidad Santiago de Cali, 2025-10-28) Galviz Velarde, Laura Manuela; Mosquera González, Sergio David (Director)Document management in laboratories dedicated to the physicochemical analysis of raw water was a fundamental component for ensuring the traceability, reliability, and availability of technical information. However, small and medium-sized enterprises (SMEs) commonly exhibited deficiencies related to the lack of standardization, inadequate version control, incomplete records, and limited use of digital tools, which affected compliance with the requirements of ISO 9001:2015 and ISO/IEC 17025:2017. The present study aimed to design a document management system tailored to the operational, organizational, and regulatory needs of an SME dedicated to raw water physicochemical analysis. A structured documentary review inspired by PRISMA guidelines was carried out, allowing the diagnosis of the current document management system, the identification of gaps in relation to international standards, and the analysis of technical best practices applicable to testing laboratories. Based on these findings, an integrated model was developed that incorporated a hierarchical structure of documents, a procedure for document control and updating, a RACI responsibility matrix, performance indicators, a training plan, and a gradual implementation strategy. The proposed system demonstrated high technical and operational viability and medium-high economic feasibility, supporting its relevance and applicability for strengthening document standardization, traceability, and efficiency. Overall, the model contributed to improving internal quality, reducing document-related nonconformities, and enhancing the laboratory’s readiness for future accreditation processes.Item Aplicación de la espectroscopia infrarroja cercana (NIR) en la industria papelera(2025-11-18) Gómez Liévano, José Eduardo; Castro Narváez, Sandra Patricia (Directora)An approach to the application of near infrared spectroscopy (NIRS) in the paper industry was made, highlighting its potential in the application for process optimization while improving product quality. The NIRS technique is presented as an effective alternative to traditional conventional methods. The methodology used included literature review through searches in scientific databases where the most relevant applications and recent studies were identified; a detailed analysis of the quality parameters that can be evaluated throughout the process, from wood characterization, pulp analysis and black liquor. Highlighting the ability of the technique to evaluate density, moisture, lignin content, cellulose, hemicellulose, fiber morphology, among others, showing its ability to provide fast and non-destructive results. The comparison of the NIRS technique with respect to traditional methods reveals that NIRS provides significant advantages by offering greater speed, minimizing the use of chemical reagents and a greater number of analyses, obtaining reliable results, allowing them to optimize the processes of the paper industries. Recommendations include further development of the technique and careful calibration to ensure statistical analysis guarantees accuracy and reliability.Item Revisión sistemática sobre el uso de NIRS como herramienta para la detección de cianuro y carotenoides en la yuca (Manihot Esculenta) identificando limitaciones y oportunidades para la seguridad alimentaria(Universidad Santiago de Cali, 2025-11-18) Ruiz Quelal, Diana Marcela; Chamorro Rengifo, Andrés Felipe (Director)Cassava (Manihot esculenta Crantz) is a staple crop in tropical and subtropical regions, providing food for over 800 million people due to its adaptability to poor soils and high starch and carotenoid content. However, its consumption carries risks due to cyanogenic glycosides, which release cyanide. To address this issue, near-infrared spectroscopy (NIRS) has emerged as a non-destructive, rapid, and accurate technique for detecting carotenoids and cyanide. This study aimed to evaluate and classify detection methods for these compounds in cassava, focusing on the efficacy and applicability of NIRS. Through a systematic analytical-descriptive review (2014–2024) of databases such as Science Direct and Web of Science, selected articles were analyzed based on the criteria of the RAI methodology. Results demonstrated that NIRS is highly effective, with models exceeding 99 % accuracy in classifying varieties based on cyanide content and showing strong correlations with reference techniques like HPLC. NIR spectroscopy emerges as an efficient and scalable tool, outperforming traditional methods in terms of speed and safety. However, its implementation requires standardized protocols to ensure consistent results. Its integration into routine monitoring systems is recommended, complemented by multivariate analysis, to optimize its application in the food and agricultural industries.Item Uso del alcohol fusel como aditivo en mezclas de combustibles: review(Universidad Santiago de Cali, 2025-12-01) Zúñiga Pino, Karen Nathalia; Orduña Ortega, Julieth (Directora); Mora Vargas, Jorge Andrés (Director)Fusel alcohol, also known as fusel oil, is a by-product composed mainly of isoamyl alcohol, obtained during the industrial processing of sugarcane for ethanol production. In recent years, its use as an additive in fuel blends has attracted growing scientific and technological interest. This review analyzed the potential of fusel alcohol as an additive in fuel mixtures, aiming to assess its technical and environmental feasibility for improving the combustion properties of gasoline. To this end, recent research was collected and discussed, complemented by relevant conventional studies. The study first addressed the production and purification processes of fusel alcohol within the ethanol manufacturing chain, highlighting the stages of fermentation, distillation, and dehydration, as well as complementary techniques such as extractive distillation and liquid–liquid extraction. Subsequently, its physicochemical properties were systematized, including composition, density, viscosity, calorific value, and octane number—parameters that determine its performance as an additive. The results of the review showed that gasoline–fusel alcohol blends (F10 and F20) increase the octane number and improve thermal efficiency, although they exhibit a reduction in calorific value and effects associated with water content. In the case of diesel blends, a significant reduction in NOx emissions was observed, accompanied, however, by increases in CO and CO₂ under certain operating conditions. Overall, the findings indicate that fusel alcohol has considerable potential as an oxygenated additive, with the capacity to be valorized as an agro-industrial by-product and to contribute to energy sustainability. Nevertheless, its large-scale utilization depends on overcoming technical limitations and advancing experimental validation at the pilot scale.Item Efecto de iones carbonato, sulfato y fosfato en la fotooxidación (UV/H2O2) de Losartán(Universidad Santiago de Cali, 2025-12-07) Cordoba Gurrute, Huber; Santiago Lerma, Isabel Cristina; Castro Narváez, Sandra Patricia (Directora)Losartan (LOS) is a widely consumed drug for the treatment of arterial hypertension and diabetic nephropathy; it is a pseudopersistent drug capable of altering the aquatic environment. This study addresses the degradation of LOS by Fenton, Photofenton and homogeneous photocatalysis systems with Fe2+, Al3+ and Cu2+ metal ions, under UV irradiation with LED lamp (280-300nm). The monitoring of LOS degradation was performed by UV spectroscopy at 253 nm. The results were analyzed in terms of percentage of contaminant degradation. The best performing pHs were: pH 8.0 for UV/LOS-H2O2-Fe2+ (88.9%) and pH 6.4 for LOS-H2O2-Cu2+ (67.0%) and LOS-H2O2-Al3+ (89.8%) systems with LOS/Mn+ molar ratios of 357:1, 357:1 and 238:1, respectively. The degradation kinetics were fitted in pseudo first order with rate constants in the Photofenton > Fenton> Photocatalysis processes; with half-life times less than 20.5 min. The addition of CO₃2- ions presented negative synergy in all treatments. However, PO₄3- ions improved the processes with Al3+ as catalyst (99.8% photofenton and 100% removal for fenton) and SO42- ions registered the highest efficiencies in the systems with Fe2+ (100% for photofenton and 70.7 for fenton). The photodegradations with Cu2+ photodegradations were generally superior without addition of anions.. The oxidation techniques performed are based on low-cost systems that can be easily implemented in water treatment systems.Item Desarrollo de materiales basados en Carboximetilalmidón/Quitosano aplicados a la remoción de colorantes en aguas(Universidad Santiago de Cali, 2025-12-11) Rivera Pillimue, Merly Alexandra; Chamorro Rengifo, Andrés Felipe (Director); Cardona Cardona, Yudy Vanesa (Directora)Water contamination due to the presence of dyes and other pollutants, such as heavy metals and pharmaceutical residues, has generated serious risks to human and animal health. Several research studies have developed strategies to remove dyes from water sources, but industries continue to generate wastewater containing dyes, which represents important environmental and ecological challenges. An effective methodology for dye removal is the use of adsorption processes with agricultural organic materials and low-cost ecological adsorbents, such as cellulose, chitosan and starch. In this sense, a hydrogel based on Carboxymethyl starch (CMA)/chitosan was developed with the objective of removing anionic dyes from aqueous sources. This was done in three stages: i) starch modification, ii) formation and characterization of the hydrogel by ionic crosslinking between CMA and chitosan, and iii) evaluation of the removal capacity of the evaluated dyes: Acid Red (AR), Acid Blue (AC), and Brilliant Blue (AB). The hydrogel formed was characterized by Fourier transform infrared spectroscopy (FTIR) to identify functional groups, confirming the modification of starch and the presence of chitosan. In addition, it was determined that the material presented retention capacities of the dyes above 70 %. Thus, this material showed high affinity for anionic dyes, presenting a high potential to be used as a dye retention agent.Item Determinación de nitrosaminas en cervezas por cromatografía de gases acoplada a espectrometría de masas y microextracción en fase sólida(Universidad Santiago de Cali, 2025-12-04) López Londoño, Sara; Estupiñán Alomia, Hilari Andrea; Ríos Acevedo, Jhon Jairo (Director)N-nitrosamines are organic compounds with carcinogenic potential and other adverse effects that pose a public health concern due to their presence in food and beverages. During the malting and fermentation process of beer, precursors such as barley or water can promote the formation of these substances. In this study, a methodology was developed for the quantification of four N-nitrosamines in craft and industrial beers using headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). This technique is characterized by being low in contamination, economical, and accurate for the determination of volatile nitrosamines. The N + (N + 1) simplex experimental method was applied for SPME extraction optimization, evaluating different parameters in order to improve peak separation and the sensitivity of the method. A better response was obtained using a PDMS fiber, an extraction time of 60 min, a sample volume of 20 ml, a temperature of 50°C, and a stirring speed of 150 RPM. On the other hand, no significant improvements in extraction efficiency were observed when modifying its ionic strength. The method was validated by determining its linearity, limit of detection (LOD), and limit of quantification (LOQ), concluding that none of the nitrosamines analyzed were present in the craft and industrial beer samples evaluated.Item Estudio computacional de tintes orgánicos basados en trifenilamina para celdas solares sensibilizadas por colorantes(Universidad Santiago de Cali, 2025-12-05) Cabrales Carvajal, Jorge Andrés; Tostado Robledo, Sergio Lennin (Director)Consistent with the objectives outlined in the United Nations Sustainable Development Goals, this theoretical study explores a number of organic compounds based on triphenylamine for potential application in dye-sensitized solar cells (DSSCs). Ground-state geometries were confirmed to be true minima by frequency analysis after optimization using DFT B3LYP/6-31G(d,p) with Gaussian09W. Electron injection into the TiO₂ semiconductor and dye regeneration via the I⁻/I₃⁻ redox pair were assessed using the resulting electronic properties, HOMO/LUMO orbitals and bandgap energies. Based on their conjugated bridges and structural variations, the dyes were categorized into two main groups, A and B. The majority of dyes demonstrated favorable energetic alignment, with spontaneous electron injection indicated by highly negative ΔGinject values (approximately –2.0 eV). Strong absorption in the visible region (400–700 nm) and high light-harvesting efficiencies (LHE between 0.93 and 1), according to UV–Vis absorption spectra computed via TD-DFT CAM-B3LYP/6-31G(d,p) for the first three electronic transitions.Item Diseño, síntesis y estudio de las propiedades optoelectrónicas de un material transportador de huecos basado en fenotiazina y difenilamina para celdas fotovoltaicas de Perovskita(Universidad Santiago de Cali, 2025-12-12) Oliveros Garavito, David; Illicachi Romero, Luis Alberto (Director); Insuasty Chamorro, Braulio Alberto (Director)The rapid growth of the world's population poses a challenge for energy production, which is still dependent on non-renewable sources such as natural gas and coal, the main contributors to the increase in greenhouse gases and other environmental impacts. In this context, renewable sources, particularly solar energy, are presented as a sustainable alternative due to their low cost, stability, and high efficiency, with perovskite solar cells standing out with efficiencies close to 25%. In this work, a new hole transport material derived from phenothiazine and diphenylamine was designed using Buchwald-Hartwig coupling, with yields exceeding 40%. The compounds obtained were characterized by ¹H NMR, mass spectrometry, and X-ray diffraction. The material showed maximum absorption at 300 nm and emission at 453 nm in THF, as well as a forbidden optical band of 2.943 eV, indicating a possible application in perovskite solar cells.