@article{ding_szymczyk_mehraban_lim_parrillo-chapman_el-shafei_freeman_2022, title={Molecular and excited state properties of photostable anthraquinone red and violet dyes for hydrophobic fibers}, volume={1248}, ISSN={["1872-8014"]}, DOI={10.1016/j.molstruc.2021.131349}, abstractNote={The molecular, spectroscopic, and excited state properties of synthetic dyes for fiber-based outdoor materials continue to be of commercial interest. Early developments in this area were reported in the 1980s, when the need for dyes for polyester (PET)-based automobile interiors gave rise to commercially viable nitrodiphenylamine yellow, anthraquinone red and blue, and azo red dyes. To augment that initial knowledge base, the present study involved the use of experimental and theoretical methods to help establish the molecular structures and excited state properties of some more recent dyes for producing photostable colors on PET fibers. Having completed the characterization of present-day scarlet, blue, and yellow disperse dyes for PET-based fibers used outdoors, our attention turned to commercially available red and violet dyes. In this regard, HPLC analysis showed that the red product was a mixture containing four components, while the violet product contained only one component. Results from 1H NMR, HRMS, and single crystal X-ray diffraction analyses indicated that the principal components were dyes having a 1-amino-4-hydroxyanthraquinone base structure. The presence of an –OH group alpha to an anthraquinone C=O moiety provides for intramolecular H-bonding and a subsequent opportunity for intramolecular proton transfer in the excited state – as a photostabilizing mechanism. Further, for both dyes, results from the analysis of Frontier HOMO and LUMO isosurfaces indicated strong HOMO-LUMO overlap without molecular gaps and were consistent with strong excited state energy dissipation in a non-destructive way.}, journal={JOURNAL OF MOLECULAR STRUCTURE}, author={Ding, Yi and Szymczyk, Malgorzata and Mehraban, Nahid and Lim, Jihye and Parrillo-Chapman, Lisa and El-Shafei, Ahmed and Freeman, Harold S.}, year={2022}, month={Jan} }
 @article{ding_szymczyk_mehraban_lim_parrillo-chapman_el-shafei_freeman_2020, title={Molecular and excited state properties of photostable yellow disperse dyes}, volume={1207}, ISSN={["1872-8014"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85078970244&partnerID=MN8TOARS}, DOI={10.1016/j.molstruc.2020.127815}, abstractNote={Textile dyes with high resistance to UV light induced fading on poly (ethylene terephthalate) (PET) fibers are important for textile substrates used in applications such as automobile interiors and outdoor furniture. Dye photostability influenced the development of dye structures for automobile fabrics dating back to the 1980s but the nature of currently used disperse dyes is less widely known. As part of a study designed to provide updates on this subject, the current investigation employed experimental and theoretical methods to determine the nature and properties of commercial dyes used to produce lightfast colors on PET fibers. Having completed the characterization of scarlet and blue disperse dyes for PET-based fabrics used outdoors, our attention turned to the characterization of commercially available lightfast yellow dyes. HPLC analysis showed that a pair of yellow products were mixtures containing three or four dyes, and the use of 1NMR, HRMS and single crystal X-ray diffraction analyses indicated that they were homologous azo–anthraquinone based dyes with or without a 1,8-bis(phenylthio)anthraquinone dye. Results from calculating Frontier HOMO and LUMO isosurfaces indicated strong HOMO/LUMO overlap, and the E0-0 for the homologous anthraquinone-based azo dyes was exactly the same (2.37 eV) which contributes to their photostability.}, journal={JOURNAL OF MOLECULAR STRUCTURE}, author={Ding, Yi and Szymczyk, Malgorzata and Mehraban, Nahid and Lim, Jihye and Parrillo-Chapman, Lisa and El-Shafei, Ahmed and Freeman, Harold S.}, year={2020}, month={May} }
 @article{ding_mehraban_szymczyk_parrillo-chapman_el-shafei_freeman_2019, title={Molecular and excited state properties of photostable anthraquinone blue dyes for hydrophobic fibers}, volume={1181}, ISSN={0022-2860}, url={http://dx.doi.org/10.1016/J.MOLSTRUC.2018.12.070}, DOI={10.1016/j.molstruc.2018.12.070}, abstractNote={Abstract Synthetic dyes having high photostability on hydrophobic fibers such as poly(ethylene terephthalate) (PET) are of interest for use on textile substrates for outdoor applications. While much is known about photostable dyes developed for PET in the 1980s, owing to their viability for use in automobile interiors, little has been published on currently viable photostable disperse dyes. As part of an effort to help fill this void and to facilitate future photostable disperse dye design, the present study involved the use of experimental measurements and modelling studies to help characterize the molecular structures of commercially viable dyes for producing photostable colors on PET fibers, beginning with a pair of blue dyes. With the aid of HR-MS, 500 MHz 1H NMR, and X-ray crystallography, it was established that the two dyes are structural isomers having 1,5-(OH)2-anthraquinone (AQ) and 1,8-(OH)2-AQ base structures. It is proposed that the photostability of these dyes arises from the presence of multiple OH/NH groups ortho to the AQ C O groups which enables them to dissipate excited state energy through intramolecular proton transfer. Further, using DFT-based molecular modelling studies, it was shown that the dye having the 1,5-(OH)2-AQ base structure has a lower ESOP than the isomeric dye having the 1,8-(OH)2-AQ base structure. Similarly, results from calculating Frontier HOMO and LUMO isosurfaces indicated that the LUMO lobes of the latter dye are larger, suggesting that this dye undergoes excitation faster than the 1,5-(OH)2-AQ isomer.}, journal={Journal of Molecular Structure}, publisher={Elsevier BV}, author={Ding, Yi and Mehraban, Nahid and Szymczyk, Malgorzata and Parrillo-Chapman, Lisa and El-Shafei, Ahmed and Freeman, Harold S.}, year={2019}, month={Apr}, pages={109–117} }
 @article{mehraban_musich_freeman_2019, title={Synthesis and Encapsulation of a New Zinc Phthalocyanine Photosensitizer into Polymeric Nanoparticles to Enhance Cell Uptake and Phototoxicity}, volume={9}, ISSN={["2076-3417"]}, DOI={10.3390/app9030401}, abstractNote={Efforts to enhance the utility of photodynamic therapy as a non-invasive method for treating certain cancers have often involved the design of dye sensitizers with increased singlet oxygen efficiency. More recently, however, sensitizers with greater selectivity for tumor cells than surrounding tissue have been targeted. The present study provides an approach to the modification of the known photosensitizer zinc phthalocyanine (ZnPc), to enhance its solubility and delivery to cancer cells. Targeting a photosensitizer to the site of action improves the efficacy of the sensitizer in photodynamic therapy. In this work we used PLGA-b-PEG to encapsulate a new zinc phthalocyanine derivative, 2(3), 9(10), 16(17), 23(24)-tetrakis-(4’-methyl-benzyloxy) phthalocyanine zinc(II) (ZnPcBCH3), to enhance uptake into A549 cells, a human lung cancer cell line. ZnPcBCH3 exhibited the same photochemical properties as the parent compound ZnPc but gave increased solubility in organic solvents, which allowed for efficient encapsulation. In addition, the encapsulated dye showed a near 500-fold increase in phototoxicity for A549 cancer cells compared to free dye.}, number={3}, journal={APPLIED SCIENCES-BASEL}, author={Mehraban, Nahid and Musich, Phillip R. and Freeman, Harold S.}, year={2019}, month={Feb} }
 @article{lim_szymczyk_mehraban_ding_parrillo-chapman_el-shafei_freeman_2018, title={Data from X-ray crystallographic analysis and DFT calculations on isomeric azo disperse dyes}, volume={21}, ISSN={["2352-3409"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85055317185&partnerID=MN8TOARS}, DOI={10.1016/j.dib.2018.10.010}, abstractNote={X-ray crystallography and DFT calculations were used to characterize the molecular nature and excited state properties of isomeric photostable azo dyes for textile fibers undergoing extensive sunlight exposure. Structural data in CIF files arising from X-ray analysis are reported and the complete files are deposited with the Cambridge Crystallographic Data Centre as CCDC 1548989 (https://www.ccdc.cam.ac.uk/structures/Search?Ccdcid=1548989) and CCDC 1548990 (https://www.ccdc.cam.ac.uk/structures/Search?Ccdcid=1548990). Data from calculating the vertical electronic excitation of 20 excited states for each dye and from calculating excited state oxidation potential (ESOP) and Frontier HOMO/LUMO isosurfaces are also presented. This data is related to the article “Molecular and excited state properties of isomeric scarlet disperse dyes” (Lim et al., 2018) [1].}, journal={DATA IN BRIEF}, author={Lim, Jihye and Szymczyk, Malgorzata and Mehraban, Nahid and Ding, Yi and Parrillo-Chapman, Lisa and El-Shafei, Ahmed and Freeman, Harold S.}, year={2018}, month={Dec}, pages={675–683} }
 @article{narayanan_chung_aguda_boy_hartman_mehraban_gupta_tonelli_2016, title={Correlation of the stoichiometries of poly-(epsilon-caprolactone) and alpha-cyclodextrin pseudorotaxanes with their solution rheology and the molecular orientation, crystallite size, and thermomechanical properties of their nanofibers}, volume={6}, ISSN={["2046-2069"]}, DOI={10.1039/c6ra23536k}, abstractNote={Pseudorotaxane nanofibers based on biomedical polymers, such as poly(ε-caprolactone) (PCL), and α-cyclodextrins (α-CD) open new horizons for a variety of biomedical applications.}, number={112}, journal={RSC ADVANCES}, publisher={Royal Society of Chemistry (RSC)}, author={Narayanan, Ganesh and Chung, Ching-Chang and Aguda, Remil and Boy, Ramiz and Hartman, Matthew and Mehraban, Nahid and Gupta, Bhupender S. and Tonelli, Alan E.}, year={2016}, pages={111326–111336} }
 @misc{mehraban_freeman_2015, title={Developments in PDT Sensitizers for Increased Selectivity and Singlet Oxygen Production}, volume={8}, ISSN={["1996-1944"]}, DOI={10.3390/ma8074421}, abstractNote={Photodynamic therapy (PDT) is a minimally-invasive procedure that has been clinically approved for treating certain types of cancers. This procedure takes advantage of the cytotoxic activity of singlet oxygen (1O2) and other reactive oxygen species (ROS) produced by visible and NIR light irradiation of dye sensitizers following their accumulation in malignant cells. The main two concerns associated with certain clinically-used PDT sensitizers that have been influencing research in this arena are low selectivity toward malignant cells and low levels of 1O2 production in aqueous media. Solving the selectivity issue would compensate for photosensitizer concerns such as dark toxicity and aggregation in aqueous media. One main approach to enhancing dye selectivity involves taking advantage of key methods used in pharmaceutical drug delivery. This approach lies at the heart of the recent developments in PDT research and is a point of emphasis in the present review. Of particular interest has been the development of polymeric micelles as nanoparticles for delivering hydrophobic (lipophilic) and amphiphilic photosensitizers to the target cells. This review also covers methods employed to increase 1O2 production efficiency, including the design of two-photon absorbing sensitizers and triplet forming cyclometalated Ir(III) complexes.}, number={7}, journal={MATERIALS}, author={Mehraban, Nahid and Freeman, Harold S.}, year={2015}, month={Jul}, pages={4421–4456} }