Docente
UFABC
Maurício D. C. Neto
Publicações
2026
Santin, Luiza R. R.; Cabello, Calvin Q.; Santos, Sandra C.; Bianchini, Daniela; Moreira, Leonardo M.; Pellosi, Diogo Silva; Machado, Antonio E. H.; Araújo, Diesley M. S.; Romani, Ana Paula; Bettanin, Fernanda; Neto, Maurício D. Coutinho; Homem-de-Mello, Paula; Oliveira, Hueder P. M.
Theoretical and experimental photophysics of the dye 1,9- dimethyl methylene blue: Effect of aggregation in complex solvent mixtures Journal Article
Em: Journal of Molecular Structure, vol. 1366, 2026, ISSN: 0022-2860.
@article{Santin2026,
title = {Theoretical and experimental photophysics of the dye 1,9- dimethyl methylene blue: Effect of aggregation in complex solvent mixtures},
author = {Luiza R. R. Santin and Calvin Q. Cabello and Sandra C. Santos and Daniela Bianchini and Leonardo M. Moreira and Diogo Silva Pellosi and Antonio E. H. Machado and Diesley M. S. Araújo and Ana Paula Romani and Fernanda Bettanin and Maurício D. Coutinho Neto and Paula Homem-de-Mello and Hueder P. M. Oliveira},
doi = {10.1016/j.molstruc.2026.146041},
issn = {0022-2860},
year = {2026},
date = {2026-08-05},
journal = {Journal of Molecular Structure},
volume = {1366},
publisher = {Elsevier BV},
abstract = {The present work is focused on physicochemical evaluations involving a phenothiazinium compound, a class of molecules widely investigated as prototypes of photosensitizers (PS) for use in Photodynamic Therapy (PDT). We have employed UV–Vis absorption, steady-state and time-resolved fluorescence spectroscopies, combined with DFT and TD-DFT simulations to understand the photophysical properties of dimethylmethylene blue (DMMB) under distinct environmental conditions. Several binary mixtures of solvents were evaluated (water-organic solvents). The results show that DMMB aggregation is strongly modulated by solvent polarity and hydrogen-bonding ability. Water-rich media favor the formation of face-to-face H-aggregates, leading to hypsochromic shifts in the absorption spectra, fluorescence quenching, and shorter excited-state lifetimes. Increasing the organic solvent fraction shifts the monomer–dimer equilibrium toward monomeric species, enhancing fluorescence quantum yields and radiative decay rates. In low-polarity solvents, higher-order aggregates are formed, giving rise to an additional blue-shifted absorption band around 500 nm. Theoretical results support a solvent-mediated aggregation mechanism and reveal the role of intramolecular charge-transfer character in the excited state. These findings provide molecular-level insight into the structure–property relationships governing the photophysics of phenothiazinium derivatives.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The present work is focused on physicochemical evaluations involving a phenothiazinium compound, a class of molecules widely investigated as prototypes of photosensitizers (PS) for use in Photodynamic Therapy (PDT). We have employed UV–Vis absorption, steady-state and time-resolved fluorescence spectroscopies, combined with DFT and TD-DFT simulations to understand the photophysical properties of dimethylmethylene blue (DMMB) under distinct environmental conditions. Several binary mixtures of solvents were evaluated (water-organic solvents). The results show that DMMB aggregation is strongly modulated by solvent polarity and hydrogen-bonding ability. Water-rich media favor the formation of face-to-face H-aggregates, leading to hypsochromic shifts in the absorption spectra, fluorescence quenching, and shorter excited-state lifetimes. Increasing the organic solvent fraction shifts the monomer–dimer equilibrium toward monomeric species, enhancing fluorescence quantum yields and radiative decay rates. In low-polarity solvents, higher-order aggregates are formed, giving rise to an additional blue-shifted absorption band around 500 nm. Theoretical results support a solvent-mediated aggregation mechanism and reveal the role of intramolecular charge-transfer character in the excited state. These findings provide molecular-level insight into the structure–property relationships governing the photophysics of phenothiazinium derivatives.
2025
Melo, Diego Ulysses; Carneiro, Leonardo Martins; Coutinho-Neto, Mauricio Domingues; Homem-de-Mello, Paula; Bartoloni, Fernando Heering
Developing a Machine Learning Model for Hydrogen Bond Acceptance Based on Natural Bond Orbital Descriptors Journal Article
Em: J. Org. Chem., 2025, ISSN: 1520-6904.
@article{Melo2025,
title = {Developing a Machine Learning Model for Hydrogen Bond Acceptance Based on Natural Bond Orbital Descriptors},
author = {Diego Ulysses Melo and Leonardo Martins Carneiro and Mauricio Domingues Coutinho-Neto and Paula Homem-de-Mello and Fernando Heering Bartoloni},
doi = {10.1021/acs.joc.5c00724},
issn = {1520-6904},
year = {2025},
date = {2025-07-06},
urldate = {2025-07-06},
journal = {J. Org. Chem.},
publisher = {American Chemical Society (ACS)},
abstract = {This study employs machine learning (ML) to assess the predictive power of electronic descriptors derived from natural bond orbital (NBO) analysis for hydrogen bond acceptance. Using a data set of 979 hydrogen bond complexes, each formed by a hydrogen bond acceptor and 4-fluorophenol as the donor, we optimized geometries via GFN2-xTB, followed by DFT single-point calculations. From these, NBO analysis was used to extract intramolecular donor–acceptor interactions, particularly the orbital stabilization energies (E(2)), which reflect electron delocalization and relate to canonical resonance structures. The E(2) values served as features to train seven ML models, based on different techniques: KNN, Decision Tree, SVM, RF, MLP, XGBoost, and CatBoost. To our knowledge, this is the first work that uses E(2) as a standalone ML descriptor for hydrogen bond acceptance. Even with a small set of descriptors, we achieved high predictive performance, with errors below 0.4 kcal mol–1, surpassing previous studies that used heterogeneous descriptors, including quantum-chemical data. Our results highlight the utility of NBO-based features in building accurate, physically meaningful, and generalizable ML models for pKBHX prediction.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This study employs machine learning (ML) to assess the predictive power of electronic descriptors derived from natural bond orbital (NBO) analysis for hydrogen bond acceptance. Using a data set of 979 hydrogen bond complexes, each formed by a hydrogen bond acceptor and 4-fluorophenol as the donor, we optimized geometries via GFN2-xTB, followed by DFT single-point calculations. From these, NBO analysis was used to extract intramolecular donor–acceptor interactions, particularly the orbital stabilization energies (E(2)), which reflect electron delocalization and relate to canonical resonance structures. The E(2) values served as features to train seven ML models, based on different techniques: KNN, Decision Tree, SVM, RF, MLP, XGBoost, and CatBoost. To our knowledge, this is the first work that uses E(2) as a standalone ML descriptor for hydrogen bond acceptance. Even with a small set of descriptors, we achieved high predictive performance, with errors below 0.4 kcal mol–1, surpassing previous studies that used heterogeneous descriptors, including quantum-chemical data. Our results highlight the utility of NBO-based features in building accurate, physically meaningful, and generalizable ML models for pKBHX prediction.
2024
Homem-de-Mello, Paula; Souza, Ana Clara Gonzalez; Melo, Diêgo U.; Mol, Gabriel S.; Souza, Jhonathan R. De; Carneiro, Leonardo M.; Nobrega, Maíra G.; Zanotto, Mateus; Corrêa, Raissa Lohanna G. Q.; Oliveira, Hueder P. M.; Bartoloni, Fernando H.; Aoto, Yuri A.; Coutinho-Neto, Maurício Domingues; Orestes, Ednilsom
DESIGN BIOINSPIRADO DE CORANTES Journal Article
Em: Quim. Nova, 2024, ISSN: 1678-7064.
@article{Homem-de-Mello2025,
title = {DESIGN BIOINSPIRADO DE CORANTES},
author = {Paula Homem-de-Mello and Ana Clara Gonzalez Souza and Diêgo U. Melo and Gabriel S. Mol and Jhonathan R. De Souza and Leonardo M. Carneiro and Maíra G. Nobrega and Mateus Zanotto and Raissa Lohanna G. Q. Corrêa and Hueder P. M. Oliveira and Fernando H. Bartoloni and Yuri A. Aoto and Maurício Domingues Coutinho-Neto and Ednilsom Orestes},
url = {https://www.scielo.br/j/qn/a/RCr5ZtRt4bVGwZhp5nxGSjP/},
doi = {10.21577/0100-4042.20250047},
issn = {1678-7064},
year = {2024},
date = {2024-09-09},
journal = {Quim. Nova},
publisher = {Sociedade Brasileira de Quimica (SBQ)},
abstract = {The history of the discovery, use, and development of dyes is closely linked to the history of humanity itself. Among the first records of human civilization are cave paintings made from, e.g., fruits, plants, minerals, and insects. Over the centuries, using different techniques, colors have been given to all types of materials and products, from clothing to food. The chemicals responsible for colors are dyes - a vast collection of molecules of the most varied compositions, but which have in common the absorption of light within the visible window of the electromagnetic spectrum. This article aims not only to review the properties of some classes of natural dyes, their origins, and their applications but also to describe the various computational chemistry methods involved in designing new bio-inspired molecules.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The history of the discovery, use, and development of dyes is closely linked to the history of humanity itself. Among the first records of human civilization are cave paintings made from, e.g., fruits, plants, minerals, and insects. Over the centuries, using different techniques, colors have been given to all types of materials and products, from clothing to food. The chemicals responsible for colors are dyes - a vast collection of molecules of the most varied compositions, but which have in common the absorption of light within the visible window of the electromagnetic spectrum. This article aims not only to review the properties of some classes of natural dyes, their origins, and their applications but also to describe the various computational chemistry methods involved in designing new bio-inspired molecules.
Sodré, Pedro Tendrih; Aguilar, Andrea Maria; Alves, Wendel Andrade; Coutinho-Neto, Maurício Domingues
Intrinsic and environmental modulation of stereoselective aldol organocatalyzed reactions by proline-containing lipopeptides Journal Article
Em: RSC Adv., vol. 14, iss. 29, pp. 21035-21046, 2024.
@article{D4RA03222E,
title = {Intrinsic and environmental modulation of stereoselective aldol organocatalyzed reactions by proline-containing lipopeptides},
author = {Pedro Tendrih Sodré and Andrea Maria Aguilar and Wendel Andrade Alves and Maurício Domingues Coutinho-Neto},
url = {http://dx.doi.org/10.1039/D4RA03222E},
doi = {10.1039/D4RA03222E},
year = {2024},
date = {2024-07-03},
urldate = {2024-01-01},
journal = {RSC Adv.},
volume = {14},
issue = {29},
pages = {21035-21046},
publisher = {The Royal Society of Chemistry},
abstract = {Proline, along with its derivatives, has been employed as an efficient organocatalyst for aldol reactions, with the ability to promote the creation of stereoselective C–C bonds. Even though the Houk–List transition state model is able to explain the stereoselectivity observed when proline is used as a catalyst, few studies investigate the role of microheterogeneous media in modulating the reaction outcome. In this work, molecular dynamics and electronic structure calculations were used to investigate the aldol reaction in the condensed phase. Our research focused on a lipopeptide compound incorporating the proline residue within the sequence PRWG-(C18H37), where P represents l-proline, R stands for l-arginine, W for l-tryptophan, and G for l-glycine. This sequence is covalently bonded to a hydrophobic segment formed by a long aliphatic chain, acting as an organocatalyst in an aqueous solution. This catalytic phase utilizes the complex chemical environment of the solution to achieve high selectivity. Our findings indicate a Houk–List-like mechanism, in which the amide acts as an H-bond donor, complemented by a mechanism in which the counter ion, trifluoracetic acid (TFA), acts as a proton shuttle. Both mechanisms demonstrated low energy barriers—12.23 and 1.42 kcal mol−1 for the (S,R) stereoisomer formation, computed using DLPNO-CCSD with def2-TZVPP basis set. Further, to explore the catalytic effect of the PRWG-(C18H37) lipopeptide in water, molecular dynamics simulations were conducted. It was observed that the micellar phase significantly enhances stereospecific encounters, favouring the experimentally observed ratio of (SR/SS) isomers, in contrast to reactions in a pure cyclohexanone medium. By quantifying the effects enabled by the supramolecular assembly, we were able to shed light on the factors that modify and enhance the stereoslectivity of the reaction.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Proline, along with its derivatives, has been employed as an efficient organocatalyst for aldol reactions, with the ability to promote the creation of stereoselective C–C bonds. Even though the Houk–List transition state model is able to explain the stereoselectivity observed when proline is used as a catalyst, few studies investigate the role of microheterogeneous media in modulating the reaction outcome. In this work, molecular dynamics and electronic structure calculations were used to investigate the aldol reaction in the condensed phase. Our research focused on a lipopeptide compound incorporating the proline residue within the sequence PRWG-(C18H37), where P represents l-proline, R stands for l-arginine, W for l-tryptophan, and G for l-glycine. This sequence is covalently bonded to a hydrophobic segment formed by a long aliphatic chain, acting as an organocatalyst in an aqueous solution. This catalytic phase utilizes the complex chemical environment of the solution to achieve high selectivity. Our findings indicate a Houk–List-like mechanism, in which the amide acts as an H-bond donor, complemented by a mechanism in which the counter ion, trifluoracetic acid (TFA), acts as a proton shuttle. Both mechanisms demonstrated low energy barriers—12.23 and 1.42 kcal mol−1 for the (S,R) stereoisomer formation, computed using DLPNO-CCSD with def2-TZVPP basis set. Further, to explore the catalytic effect of the PRWG-(C18H37) lipopeptide in water, molecular dynamics simulations were conducted. It was observed that the micellar phase significantly enhances stereospecific encounters, favouring the experimentally observed ratio of (SR/SS) isomers, in contrast to reactions in a pure cyclohexanone medium. By quantifying the effects enabled by the supramolecular assembly, we were able to shed light on the factors that modify and enhance the stereoslectivity of the reaction.
2023
Almeida, James M.; Ferreira, Conny Cerai; Bandeira, Lucas; Cunha, Renato D.; Coutinho-Neto, Maurício Domingues; Homem-de-Mello, Paula; Orestes, Ednilsom; Nascimento, Regina Sandra Veiga
Em: The Journal of Physical Chemistry B, vol. 0, não 0, pp. null, 2023, (PMID: 37871185).
@article{doi:10.1021/acs.jpcb.3c01707,
title = {Synergistic Interaction of Hyperbranched Polyglycerols and Cetyltrimethylammonium Bromide for Oil/Water Interfacial Tension Reduction: A Molecular Dynamics Study},
author = {James M. Almeida and Conny Cerai Ferreira and Lucas Bandeira and Renato D. Cunha and Maurício Domingues Coutinho-Neto and Paula Homem-de-Mello and Ednilsom Orestes and Regina Sandra Veiga Nascimento},
url = {https://doi.org/10.1021/acs.jpcb.3c01707},
doi = {10.1021/acs.jpcb.3c01707},
year = {2023},
date = {2023-10-23},
journal = {The Journal of Physical Chemistry B},
volume = {0},
number = {0},
pages = {null},
abstract = {Applying surfactants to reduce the interfacial tension (IFT) on water/oil interfaces is a proven technique. The search for new surfactants and delivery strategies is an ongoing research area with applications in many fields such as drug delivery through nanoemulsions and enhanced oil recovery. Experimentally, the combination of hyperbranched polyglycerol (HPG) with cetyltrimethylammonium bromide (CTAB) substantially reduced the observed IFT of oil/water interface, 0.9 mN/m, while HPG alone was 5.80 mN/m and CTAB alone IFT was 8.08 mN/m. Previous simulations in an aqueous solution showed that HPG is a surfactant carrier. Complementarily, in this work, we performed classical molecular dynamics simulations on combinations of CTAB and HPG with one aliphatic chain to investigate further the interaction of this pair in oil interfaces and propose the mechanism of IFT decrease. Basically, from our results, one can observe that the IFT reduction comes from a combination of effects that have not been observed for other dual systems: (i) Due to the CTAB-HPG strong interaction, a weakening of their specific and isolated interactions with the water and oil phases occurs. (ii) Aggregates enlarge the interfacial area, turning it into a less ordered interface. (iii) The spread of individual molecules charge profiles leads to the much lower interfacial tension observed with the CTAB+HPG systems.},
note = {PMID: 37871185},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Applying surfactants to reduce the interfacial tension (IFT) on water/oil interfaces is a proven technique. The search for new surfactants and delivery strategies is an ongoing research area with applications in many fields such as drug delivery through nanoemulsions and enhanced oil recovery. Experimentally, the combination of hyperbranched polyglycerol (HPG) with cetyltrimethylammonium bromide (CTAB) substantially reduced the observed IFT of oil/water interface, 0.9 mN/m, while HPG alone was 5.80 mN/m and CTAB alone IFT was 8.08 mN/m. Previous simulations in an aqueous solution showed that HPG is a surfactant carrier. Complementarily, in this work, we performed classical molecular dynamics simulations on combinations of CTAB and HPG with one aliphatic chain to investigate further the interaction of this pair in oil interfaces and propose the mechanism of IFT decrease. Basically, from our results, one can observe that the IFT reduction comes from a combination of effects that have not been observed for other dual systems: (i) Due to the CTAB-HPG strong interaction, a weakening of their specific and isolated interactions with the water and oil phases occurs. (ii) Aggregates enlarge the interfacial area, turning it into a less ordered interface. (iii) The spread of individual molecules charge profiles leads to the much lower interfacial tension observed with the CTAB+HPG systems.
Corrêa, Raissa Lohanna Gomes Quintino; Moraes, Matheus Morato Ferreira; Oliveira, Kléber Thiago; Aoto, Yuri Alexandre; Coutinho-Neto, Maurício Domingues; Homem-de-Mello, Paula
Diving into the optoelectronic properties of Cu(II) and Zn(II) curcumin complexes: a DFT and wavefunction benchmark Journal Article
Em: J Mol Model, vol. 29, não 5, 2023, ISSN: 0948-5023.
@article{Corrêa2023,
title = {Diving into the optoelectronic properties of Cu(II) and Zn(II) curcumin complexes: a DFT and wavefunction benchmark},
author = {Raissa Lohanna Gomes Quintino Corrêa and Matheus Morato Ferreira Moraes and Kléber Thiago Oliveira and Yuri Alexandre Aoto and Maurício Domingues Coutinho-Neto and Paula Homem-de-Mello},
doi = {10.1007/s00894-023-05560-1},
issn = {0948-5023},
year = {2023},
date = {2023-05-01},
journal = {J Mol Model},
volume = {29},
number = {5},
publisher = {Springer Science and Business Media LLC},
keywords = {},
pubstate = {published},
tppubtype = {article}
}