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Project Theme 14: Femtosecond Near-Field Optical Microscopy of Photoexcitable Biointerfaces
Many organisms utilize photoactive proteins in photoreceptors or photosynthetic light harvesting complexes to convert light to chemical energy. Such proteins could be functionalized on substrates to serve as biomimetic implants (e.g., for the retina), optical biosensors, memory elements for optical computers, or as models for renewable energy biotechnologies. This study is designed to elucidate the photoexcitation and energy transfer mechanisms of model photoactive proteins, such as bacteriorhodopsin. The chromophore of bacteriorhodopsin consists of the conjugated molecule retinal, which is covalently bound to the backbone of the photoactive protein through a protonated Schiff-base linkage. An essential aspect of the light harvesting process is a series of electronic and conformational changes that can be tracked spectroscopically (57, 58). However, the electronic and geometrical structures of the spectroscopically distinct intermediate species are only now beginning to emerge, and their functional role in the proton pumping process is completely understood.
We will use a novel microscope currently under development at Rutgers to study the photoexcitation and energy transfer dynamics of the individual bacteriorhodopsin molecules, as well as its isolated retinylidine chromophore, anchored to a suitable substrate (e.g. SiO2 or hydrogen terminated Si(111)). The instrument is based on an apertureless scanning near-field optical microscope (ASNOM), in which light scattering from a sharp metal tip scanned across the substrate provides images with nanometer spatial resolution. Femtosecond laser pulses will initiate the photochemical reaction cycle, and resulting electronic and conformational changes will be optically imaged with time-delayed probe pulses. With this optical pump-probe method we will obtain images for given values of the delay time between pump and probe pulses. Images of increasing delay time can then be assembled as actual movies of the dynamical process with femtosecond time resolution.
The ASNOM being developed in our lab will have the capability to detect and image major photoinduced conformational changes, as well as to follow the electronic excitation and energy transfer dynamics on a femtosecond time scale. Structural characterization of photoexcitable biointerfaces will be performed by infrared spectroscopy, and photo-induced dynamics will be evaluated using femtosecond fluorescence, absorption, and Raman spectroscopies.
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11:45 am - 1 pm, Room CCR-201 (Note: change of location!) awarded 2-year pre-doctoral fellowship from New Jersey Commission on Cancer Research for his research "Immune Targeting using an Engineered Vaccine Delivery System", advised by Professors Martin Yarmush and Edmund Lattime winners of the Best Poster Awards at the Biointerfacial IGERT Symposium on April 11th Congratulations to: Professor Charlie Roth, selected to receive a Warren L. Susman Award for Excellence in Teaching "for his outdstanding service in stimulating and guiding the intellectual development" of Rutgers students; and to Prof. Noshir Langrana, recipient of a Faculty- Scholar Teacher Award, which honors faculty members whose research "informs and adds excitement to their teaching and ...stimulates and informs students' scholarship." 11:45am-1 pm, Room 122, BME Bldg. Friday April 11, 2008; 8:00 am - 1:30 pm; Busch Dining Hall, Rooms A&B. Research Talks & Posters by IGERT Trainees; Plenary Talk by Prof. Scott Diamond, U. Penn; [Agenda and Roster of Talks and Posters] 11:45 am-1 pm, Room 122, BME Bldg. 11:45 am-1:00 pm, Room 122, BME Bldg. Topic: Novel Anionic Block Copolymers for Oligonucleotide Delivery Presenter: Lavanya Peddada, IGERT Trainee Panelists Tim Maguire (Merck & Co.), Eric Novik (Hurel Corp.), and Bala Subramanian (Goldman Sachs) will discuss early career opportunities for graduate students and postdocs in math, science, and engineering. Monday Nov 26; 5:00 - 6:30 pm; Center Hall, Busch Campus Ctr; sign-up required; call Career Services at (732) 445-6127, ext. 0 Topic: The Effects of Substrate Rigidity on Synaptogenesis and Dendrite Branching Speaker: Michelle Previtera, IGERT Trainee Topic: IGERT on Biointerfaces: Milestones Crossed and New Challenges Ahead Presenter: Professor Prabhas Moghe, IGERT Program Director Topic: Relationship of Chemotherapeutic Dose-Response Curves to Cell Cycle Effects Presenter: Salaheldin Hamed, IGERT Graduate Training Fellow All IGERT Trainees are actively working toward publications. Jose Fernandez and Matthew Treiser, Cohort II/III trainees leading with the most crossdisciplinary publications, will receive the 2007 IGERT Scholarly Excellence Awards. Charles Florek and Nicole Plourde deserve honorary mention. Congratulations to IGERT Graduate Trainee Mike Wininger, selected for the NSF's 2007 East Asian Pacific Summer Institute and awarded an internship for stem cell research at the National Taiwan University. was held on October 20, 2006, featuring presentations by all Trainees and Plenary Lecture by Christopher Chen, MD,PhD; U. Penn. [agenda, talks/posters ] Congratulations to our newest Graduate Training Fellows: Lavanya Peddada, Kevin Nikitczuk, Michelle Previtera and Jocie Harris.
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| Rutgers IGERT on Biointerfaces holds Inaugural Celebration and Research Seminars on January 30, 2004 The Fall 2004 class of IGERT Graduate fellows has been announced. To view information about the new fellows, please click here. Rutgers has been awarded the first NIH postdoctoral program in Tissue Engineering. Rutgers to house the first NIH-resource center for polymeric biomaterials. New Undergraduate Research Frontiers Program, ISURF launched June 2004 Rutgers has been awarded its first and New Jersey\'s second IGERT Grant.(Rutgers Media Relations) (Targum Coverage) |