Date of Award
M.S. in Pharmaceutical Science
Dr. Seongbong Jo
Dr. Michael Repka
Dr. Eman Ashour
University of Mississippi
Since its discovery, the fluorescent dye known as methylene blue has been employed in a variety of scientific disciplines. Methylene blue (MB) for intraoperative fluorescence imaging has only lately been employed. 10-N-carbamoyl linkage modification of Methylene blue helps us in developing compounds with off-to-on fluorescence switch in the presence of near infrared (NIR). Due to its naturally induced photodamage to normal tissues and deeper penetration of lesion regions when compared to UV and visible light, near infrared (NIR) light is considered favorable among the broad radiation range. The previously synthesized derivatives are not completely soluble in water, they require other co-solvents, acetone etc. So in this study branched polyethyleneimine which is a water soluble polymer is used to conjugate with methylene blue to effect the 10-N-Carbamoyl linkage. The branched structure of polyethyleneimine has several primary amines, so the amount of methylene blue that can be conjugated can also be varied. The carbamoyl linkage with methylene blue is also sensitive to hydroxyl radical. Using this hypothesis the activity was verified using hemoproteins such as hemoglobin. Subsequently this property can be used in the lysis of the malaria parasite.
MB and PEI conjugate was synthesized and tested in vitro for the cleavage of the 10-N-Carbamoyl linkage. As the result, PEI-conjugated MB successfully demonstrated the cleavage and also sensitivity to ROS-induce cleavage to release intact MB.
Alluri, Rohit, "Synthesis and Charecterisation of Methylene Blue Derivatives" (2022). Electronic Theses and Dissertations. 2418.