Alexander Greer

Professor, Department of Chemistry
The City University of New York, Brooklyn College

Past-President: American Society for Photobiology

Co-chair: Committee of Concerned Scientists

Associate Editor: Photochemistry and Photobiology

Board of Editors: Structural Chemistry

Co-editor: The Chemistry of Peroxides, Volume 3 (John Wiley & Sons), 2014.

Department of Chemistry
Graduate Center and CUNY
Brooklyn College
Brooklyn, New York 11210

Phone: 718-951-5000 ext. 2830
Fax: 718-951-4607


Alexander Greer is a professor of organic chemistry at Brooklyn College of the City University of New York (CUNY). With experience in photochemistry, singlet oxygen reactions, peroxy intermediates, and photodynamic therapy, our group sees these fields as flourishing with many developments on the horizon. Basic photochemistry that leads to latent dark effects in phototherapy presents a major challenge in research. A better understanding of complex photochemical processes is therefore urgently needed. Our group is excited to help provide mechanistic insights to sort out the reactive oxygen intermediates in photooxidation reactions. A crucial step is to solve sequential light and post-illumination processes, which are often mechanistically inaccessible. The group utilizes both experimental and theoretical methods to research fundamental aspects in the photosciences, including a focus on controlling and amplifying the production of reactive oxygen intermediates. Our research provides synthetic and mechanistic studies that facilitate the deconvolution of photochemical processes, a vital component to the improvement of fundamental and medical understanding. Broader implications include latent effects in the phototherapy of ovarian cancer and toxicity of free radical particulates. Our work is currently funded by the National Science Foundation.



Techniques to be learned upon doing lab rotations may include: Methods in Photochemistry and Photosensitization, Organic Synthesis, and Drug Design; Nanotechnology; NMR and LCMS Techniques, Laser Spectroscopy and Biomedical Engineering, Cell Culturing, Sustainable Engineering and Green Chemistry, and Computational Methods.

Goutam Ghosh (postdoctoral fellow); Serah Essang, Akshaya Iyer, Lloyd Lapoot, Kamrun Nahar, and Oliver Turque (Ph.D. students); Rekha Bhusal (Master's student); Johirul Bipu, Yolette Bukai, Devorah Scheinfeld; Ikhil Yevdayev, and Sharon Yunayev (undergraduate students); Begimai Djumagluova and Mason Yeung (high school students)


PUBLICATIONS 2020 - present

[(a) Ph.D. student; (b) MS student; (c) Undergraduate student; (d) Research assistant at Brooklyn College]

  1. L. Lapoot(a); S. Jabeen(a); A. M. Durantini; Greer, A. “Role of Curvature in Acridone for 1O2 Oxidation of a Natural Product Homoallylic Alcohol: A Novel Iso-hydroperoxide Intermediate” Photochem. Photobiol. 2024, 100, 455-464. 
  2. S. Venkataramani and A. Greer, “Special Issue devoted to Photosciences in India” Photochem. Photobiol. (forthcoming).
  3. The Chemistry of Nitrogen-rich Functional Groups, Vol. 2, J. F. Liebman and A. Greer (eds.), John Wiley & Sons, Chichester, UK, 2024.
  4. H. B. Ihalagedara, Q.-F. Xu, A. Greer and A. M. Lyons “Singlet Oxygen Generation on a Superhydrophobic Surface: Effect of Photosensitizer Coating and Incident Wavelength on 1O2 Yields. Photochem. Photobiol2024, in press.
  5. L. Lapoot; C. Wang; S. Matikonda; M. J. Schnermann; A. Greer “Bluer Phototruncation: Retro-Diels-Alder of Heptamethine Cyanine to Trimethine Cyanine through an Allene Hydroperoxide IntermediateJ. Org. Chem., 88, 17430-17437.
  6. J. Otero-González; W. Querini-Sanguillén; D. Torres-Mendoza; I. Yevdayev; S. Yunayev; K. Nahar; B. Yoo; A. Greer; D. Fuentealba; J. Robinson-Duggon “On the Mechanism of Visible-Light Sensitized Photosulfoxidation of Toluidine Blue O” Photochem. Photobiol. DOI: 10.1111/php.13882.
  7. C. C. Tonon; A. Nara de Sousa Rastelli; C. Bodahandi; G. Ghosh; T. Hasan; Q. Xu; A. Greer; A. M. Lyons “Superhydrophobic Tipped Antimicrobial Photodynamic Therapy Device for the in-vivo Treatment of Periodontitis using a Wistar Rat Model ACS Appl. Mater. Interfaces 2023,15, 50083-50094.
  8. S. Essang(a); A. Greer “Shades of Phototoxicity of Fluorescent Imaging Agents (That are Not Supposed to be Phototoxic)” Photochem. Photobiol. 2023, DOI: 10.1111/php.13856
  9. A. M. Durantini;  L. Lapoot(a); S. Jabeen(a); G. Ghosh; J. Bipu(c); S. Essang(a); B. C. Singh(a); A. Greer "Tuning the 1O2 Oxidation of a Phenol at the Air/Solid Interface of a Nanoparticle: Hydrophobic Surface Increases Oxophilicity" Langmuir 202339, 11134-11144.
  10. A. Greer and J. Cadet “Preface: 50th American Society for Photobiology Anniversary IssuePhotochem. Photobiol. 202399, 197-198. (See: table of contents)
  11. M. S. Baptista; J. Cadet; A. Greer; A. H. Thomas “Practical Aspects in the Study of Biological Photosensitization Including Reaction Mechanisms and Product Analyses: A Do’s and Don’ts Guide” Photochem. Photobiol. 2023, 99, 313-334.
  12. O. Turque(a); R. M. O’Connor(c); A. Greer "Singlet Oxygen’s Potential Role as a Nonoxidative Facilitator of Disulfide S–S Bond Rotation" Photochem. Photobiol. 2023, 99, 652-660.

  13. S. Jabeen(a); G. Ghosh; L. Lapoot(a)A. M. Durantini; A. GreerSensitized Photooxidation of ortho-Prenyl Phenol: Biomimetic Dihydrobenzofuran Synthesis and Total 1O2 Quenching”  Photochem. Photobiol. 2023, 99, 637-641. 
  14. J. L. F. Castro; M. J. Sosa; G. Petroselli; R. Erra-Balsells; M. I. Quindt; S. M. Bonesi; A. Greer; E. M. Greer; A. H. Thomas; M. Vignoni “Synthesis, Characterization, and Photocleavage of Bis-decyl Pteroic Acid: A Folate Derivative with Affinity to Biomembranes Photochem. Photobiol. 2023, 99, 593-604.
  15. M. S. Oliveira; K. F. D. N. Santos; R. M. de Paula; L. C. Vitorino; L. A. Bessa; A. Greer; P. Di Mascio; J. C. P. De Souza; C. C. G. Martin-Didonet “Nitric Oxide Detection by a Chemical Trap Method for Applications in Bacterial SystemsMicroorganisms 2023, 11, 2210.
  16. B. Malek(b); W. Lu;  P. P. Mohapatra; N. Walalawela(a); S. Jabeen(a); J. Liu; A. Greer “Probing the Transition State-to-Intermediate Continuum: Mechanistic Distinction Between a Dry vs Wet Perepoxide in the Singlet Oxygen ‘Ene’ Reaction at the Air-Water Interface” Langmuir 202238, 6036-6048.
  17. E. M. Greer; V. Siev; A. Segal; A. Greer; C. Doubleday “Computational Evidence for Tunneling and a Hidden Intermediate in the Biosynthesis of Tetrahydrocannabinol” J. Am. Chem. Soc2022, 144, 7646-7656.
  18. A. Greer, “Violet-blue Light Induces ‘Natural’ Photodynamic Plasma Disinfection with Endogenous Sensitizers” Photochem. Photobiol. 202298, 513-515.
  19. C. C. Tonon; Xu, Q.; Ghosh, G.; S Ashraf; A. Nara de Sousa Rastelli; T. HasanA. Greer; A. L. Lyons “Evaluation of Photosensitizer-Containing Superhydrophobic Surfaces for the Antibacterial Treatment of Periodontal Biofilms” J. Photochem. Photobiol. B 2022233, 112458.
  20.  M. Rashid(c); D. D. Baker(c); A. Greer “Two-Step Two-Intermediate Photorelease Bolm-McCulla Reaction: Dual Release of Nitrene and Atomic Oxygen Reactive Intermediates” Photochem. Photobiol. 202197, 1453-1455.
  21. A. Greer, “Preface: Edward L. Clennan Retirement Special Issue of Photochemistry & PhotobiologyPhotochem. Photobiol. 2021, 97, 1166-1167.
  22. M. S. Baptista; J. Cadet; A. Greer; A. H. Thomas “Photosensitization Reactions of Biomolecules: Definition, Targets, and Mechanisms” Photochem. Photobiol. 2021, 7, 1456-1483.
  23. C. C. Tonon; S. Ashraf; J. Q. Alburquerque; A. Nara de Sousa Rastelli; T. HasanA. M. Lyons; A. Greer “Antimicrobial Photodynamic Inactivation Using Topical and Superhydrophobic Sensitizer Techniques: A Perspective from Diffusion in Biofilms” Photochem. Photobiol. 2021, 97, 1266-1277.
  24. S. S. Matikonda; D. A. Helmerich; M. Meub.; G. Beliu.; P. Kollmannsberger; A. Greer; M. Sauer; M.J. SchnermannDefining the Basis of Cyanine Phototruncation Enables a New Approach to Single Molecule Localization Microscopy ACS Cent. Sci. 2021, 7, 1144-1155. Highlighted in C&E News.
  25. S. J. Belh(a); G. Ghosh; A. Greer “Surface-radical Mobility Test by a Self-sorting Mechanism: Symmetrical Product upon Recombination (SPR)” J. Phys. Chem. B 2021125, 4212-4220.
  26. A. M. Durantini; A. Greer “Interparticle Delivery and Detection of Volatile Singlet Oxygen at Air/solid Interfaces” Environ. Sci. Technol. 2021553559-3567.
  27. R. M. O’Connor(c); A. Greer “How Tryptophan Oxidation Arises by ‘Dark’ Photoreactions from Chemiexcited Triplet Acetone” Photochem. Photobiol. 202197, 456-459.

  28. A. M. Durantini; P. P. Mohapatra; M. Ashaque(c); M. E. Zatoulovski(c); M. M. Kim; K. A. Cengel; T. M. Busch; T. C. Zhu; A. Greer “Photooxidative Vulnerability to Intralipid in Photodynamic Therapy” In Periodical Reports in Photochemistry of the Royal Society of Chemistry; Protti, S.; Raviola, C. Eds.; Cambridge, UK (2021), Vol. 48, 411-422.

  29. J. Robinson-Duggon; N. Pizarro; G. Gunther; D. Zúñiga-Núñez; A. M. Edwards; A. Greer; D. Fuentealba “Fatty Acid Conjugates of Toluidine Blue O as Amphiphilic Photosensitizers: Synthesis, Solubility, Photophysics, and Photochemical Properties” Photochem. Photobiol. 2021,97, 71-79.
  30. M. J. Sosa; M. N. Urrutia; P. L. Schilardi; M. I. Quindt; S. Bonesi; D. Denburg; M. Vignoni; A. Greer; E. M. Greer; A. H. Thomas “Mono- and Bis-Alkylated Lumazine Sensitizers: Synthetic, Molecular Orbital Theory, Nucleophilic Index, and Photochemical StudiesPhotochem. Photobiol. 202197, 80-90.

  31. O. Turque(a); A. Greer; O. R. Wauchope “Synthetic Feasibility of Oxygen-driven Photoisomerizations of Alkenes and Polyenes” Org. Biomol. Chem. 2020, 18, 9181-9190.

  32. S. Jabeen(a); M. Farag(c); B. Malek(b); R. Choudhury; A. Greer "A Singlet Oxygen Priming Mechanism: Disentangling of Photooxidative and Downstream Dark EffectsJ. Org. Chem. 2020, 85, 12505-12513.
  33. M. S. Oliveira; G. Chorociejus; J. P. F. Angeli; G. M. V. V. Safadi; G. L. B. Aquino; G. E. Ronstein; L. F. Barbosa; M. C. Oliveira; M. H. G. Medeiros; A. Greer; P. Di Mascio “Heck Reaction Synthesis of Anthracene and Naphthalene Derivatives as Traps and Clean Chemical Sources of Singlet Molecular Oxygen in Biological SystemsPhotochem. Photobiol. Sci. 202019, 1590-1602.

  34. G. Ghosh; A. Greer “A Fluorinated Phosphite Traps Alkoxy Radicals Photogenerated at the Air/solid Interface of a Nanoparticle” J. Phys. Org. Chem. 2020, e4115.

  35. D. Aebisher; D. Bartusik-Aebisher; S. J. Belh(a); G. Ghosh; A. M. Durantini; Y. Liu; A. M. Lyons; A. Greer “Superhydrophobic Surfaces as a Source of Airborne Singlet Oxygen Through Free Space for Photodynamic TherapyACS Appl. Bio Mater. 2020, 3, 2370-2377.

  36. T. Hasan; D. Kessel; A. Greer “Thomas Dougherty Memorial Issue of Photochemistry & Photobiology: PrefacePhotochem. Photobiol. 2020, 96, 453.

  37. B. Ortel; S. Jabeen(a); A. Greer "Adjuvants that Empower the Action of Photodynamic TherapyPhotochem. Photobiol. 2020, 96, 725-727.

  38. S. Jabeen(a); A. Greer; K. F. Edwards; J. F. Liebman “Why are the Elemental Nonmetals (F2, Cl2, Br2, I2, S8, P4) of so Many Hues or of Any Hues and Where is the Chromophore? Insight into Intera‐X–X Bonds" Photochem. Photobiol. 2020, 96, 1140-1143.
  39. A. Greer “In Vivo Tissue Evaluation Reveals Improvements in Explicit PDT Dosimetry Photochem. Photobiol. 2020, 96, 437-439.

  40. G. Ghosh; H. Yin; S. M. A. Monro; T. Sainuddin; A. Greer; S. A. McFarland “Synthesis and Characterization of Ru(II) Complexes with π-Expansive Imidazophen Ligands for the Photokilling of Human Melanoma Cells Photochem. Photobiol. 2020, 96, 349-357 (Jarod Finlay memorial issue).


Accompanying website


Assistant Professor (1999-2003), Associate Professor (2004-2007), Professor (2008-present) at the Graduate Center and CUNY Brooklyn College.