Molecular Photonics Chemical Physics Lab, chrupn@lsu.edu Department of Chemistry Louisiana State University, Baton Rouge LA 70803
Name:
Dr Kresimir Rupnik, Ph.D.
Citizen: USA
Office:
Department of Chemistry,
Phone:
(225) 205-1353 (work cell phone, 24/7)
(225) 578-2945 (Chemistry, LSU)
E-mail/web:
chrupn@lsu.edu
or
rupnik@intelliom.com
http://www.intelliome.com
Field of specialization: Chemical/Molecular Physics-photonics, Physical- Analytical- Chemistr
Using OM PPS methods we can highly selectively identify many key details of electron-spin structures and processes in all molecular systems and in various different spectral regions from X-ray to IR and beyond. Key decision making steps in these processes are characterized by ultrafast (femto and sub-femto) time scales and therefore require highly selective spatially-temporally and objects resolved methods � such as those that we now develop in the unique environment of cells 1-3-5 at the NHMF laboratory. With well-defined precise PPS Spatio-Temporal Electro-Magnetic Processes/structures (STEMP) based on 25T field and < 15 fs laser pulses we can identify signatures of molecular processes better than 10-9 in comparison to similar non-PPS methods. Using <20fs and 25T Split-helix magnet at NHMF lab we have developed and tested OM PPS configurations (July 2014, cell 5) that can monitor previously unseen electron-spin couplings and correlations, even in soft matter systems of our interest. Earlier, we have successfully used <100fs sub-K (3He) - high magnetic flux (~10 T, cell 1) PPS instrumentation setup at the NHMF Laboratory. Indeed, OM PPS studies can significantly improve our understanding of electronic processes and structures even in the most complex processes of paramount interest in medicine: our recent discoveries at LSU and NHMF opened a completely new insight into the various different forms of Fe-S clusters in some key enzymes. Clear PPS signatures of electron (de)localization in active units are for the first time detected. Such active centers are known to be involved in the reduction-oxidation, ET, catalysis, biosynthesis and photosynthesis, as well as controlled synthesis. NHMFL and LSU work at higher magnetic fields resulted in new findings about the fundamental electron spin related properties which challenge earlier model predictions. For example, our recent studies of the magnetic PPS VT-MCD signatures of the key steps in the reduction processes of some nitrogenase related Fe-S clusters and the ongoing TO studies have been accepted in the scientific community with great interest. They not only challenge previous predictions and interpretations, but also provide a solid base for novel STEMP-based electron interaction models development.
Recent projects:
Probing Unusual Hidden Electron Dynamics in Molecules of Biomedical Interest Using Soft PPS Radiation Signatures (RS) in the Framework of Attomechanics Models
Summary
Unbiased RS models were originally introduced to study ultrafast, relatively
higher energy events in systems of biomedical interest [1]. That work continued
with the study of causal relations between electron attodynamics and the
interacting (driving) radiation by measuring characteristic electron RS, that is
the observed signatures of such interactions. During the last decade our
Polarization Phase Selective (PPS) High Magnetic Field (HMF) instrumentation and
methods developed in the framework of new integrative attomechanics modeling
significantly improved [2-3]. That allowed inclusion of soft HMF PPS RS for
studies in the energy region of chemical reactions in large, complex and
unstable bio-molecules, �far from equilibrium�. Our main challenges are highly
selective RS extractions from large sets of interfering components.
Scientifically important question we address here is: can these methods probe
electrons during protein synthesis and activity, or during interactions with
other molecules, like radical SAM. Contrary to what has been suggested in
literature, our magnetooptic studies already provide conclusive evidence about
electron locations and actions in some studied enzyme reactions. However, some
of our most important findings are related to the previously unseen electron
dynamics and new protein configurations. Indeed, we can separate signatures from
previously indistinguishable proteins that show small structural but paramount
activity differences, and we can separate (symmetrical) signatures from recently
discovered unusual and previously unseen electron spin-flips [4]. Such events
can be hidden or �dark� due to the overlappings and interferences. We estimate
that controlling window for such events starts at tens of femtoseconds or in
some cases even shorter time.
Biomedicine
Present published models describing electron dynamics and structure are known to be incomplete and both theoretical and experimental methods are inadequate for the broader goals of our funding agencies and the emerging needs of society in areas such as materials, environment, energy , medicine, etc. . Given those challenges and (too) many failures of methods used today to address them, new science and many existing open questions desperately require fundamentally new and alternative methods. Our integrative theoretical and experimental projects are aimed at advancing research in the areas of paramount interest to both understanding electronic structure at its own spatio-temporal level as well as applications in the areas of paramount interest to biomedicine at the protein/enzyme functions level. So far the results show significant advancement in better understanding electrons attomechanics as well as in introducing new biomedical science and discoveries. In many aspects, the last decade of PPS RS HMF brought a very different view and much better understanding of electrons dynamics in a broader range of investigations: from Rydberg, valence and inner electrons to the details of electrons-electromagnetic forces couplings. Among other successes in applications, newly found science presented in this work has also potentially high impact in advancing individual medicine.
Previous
results and ongoing work
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(A) Reversible redox titration of
ΔnifB
NifEN, where a Nernst curve is represented by
the solid line. Blue and red points represent
samples used to collect the MCD spectra in panel
B. (B) MCD spectra of
ΔnifB
NifEN
|
HMF-PPS
measurements can improve our understanding of
electronic processes in enzymes even in the most
complex environments of paramount interest to
biophysics and medicine, Our OMPPS high field
measurements |
and
findings about FeS based electronic
processes challenge earlier model predictions
(Rupnik at all JACS, 2011-12,
Biophysics 2014). Of interest is ongoing
12fs PPS OM study that could provide inside in
selective correlated electronic events. |
. (A) MCD spectra of IDS-oxidized
ΔnifB
NifEN (red) and
ΔnifH
MoFe protein (green, scaled by a factor of 0.5).
(B) First derivative MCD spectra of oxidized
ΔnifB
NifEN (red) and
ΔnifH
MoFe protein (green, scaled by a factor of 0.5),
showing nearly identical transitions in both
cases. (C) MCD spectra of reduced
ΔnifB
NifEN (red) and
ΔnifH
MoFe protein |
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MCD magnetization
of L127DFe-MoFe
Av 1
protein, at ~500mK @ 410nm, a multi-component
spin system
At NHMF
lab, we canobtained much higher selectivity
which resulted in new information about
enzymatic structures and synthesis patterns.
|
MCD magnetization of
Av1
DnihB MoFe:
blue,
at
1.63K
@ 520nm (LSU), red at 1.577K @410nm
(NHMF, this work covers 10T).
Pulses~100fs, 70MHz
|
FSHM
measurements- magnetizations of porphyrin FeCl(TPP)
shown from
-24.5 to 24.5 T |
Typical UF OM
PPS- differential PPS magnetization curve
- ~15fs
, 800nm centered pulse directed into
electronic transitions area.
MCD curve
is shown below. Events are driven in
broadband region, 80
MHz |
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FSHM
measurements- MCD of porphyrin FeCl(TPP)
shown from
-24.5 to 24.5 T measurements. A larger
set of porphyrins is investigated for new
unexpected electronic structures
|
OM PPS spectra of
a Fe4S4- protein.
Temperature with sapphire windows ~10K. A shift
of the peak at 520->580nm is observed at VT.
Results are different from low field: different
view of correlated coupled electrons |
Typical UF OM
PPS- differential PPS structure - ~15fs
, 800nm centered pulse directed into
electronic transitions area.
Magnetization curve
is shown above from 0 to 25T. Events are
driven in broadband region |
High OM PPS can
significantly modulate temporal phase and also
help
selectively resolve diferent spatio-temporal
contributions. We investigate now presence of
oscillatory structures below 100fs. Here some
models predict new important couplings |
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OUR OM HF UF PPS
~ 15fs measurements
in various different spectral regions is
based on several new PPS technological solutions |
Sample
preparation and presentation
technology
presents one of the most
significant
challenges and one of the great successes of the
previous OM PPS
work at NHMFL. |
At sub 15fs ,
STEMPS measurements and characterizations
require new instrumental configurations for
photonic auto- and cross-correlations |
Femtosecond scale signal from a PPS.PPS method
provide multidimensional data: spatial, temporal
frequency, and phase information-higher
selectivity and better STEMP resolution.
Polarization
selection is achieved with two polarizers. |
Professional:
1986-present
Faculty-Research Scientist, Department of
Chemistry,
1984-85
Postdoctoral Researcher in Physical Chemistry,
Department of
Chemistry, University of North Carolina, Chapel Hill, NC
(NSF)
Awarded Projects/Grants:
Research in the last 20 years included projects supported by NSF, USDoA, NIH,
DOD, DOE and other funding agencies.
-NSF(Collaborative Investigator) � (September2012-5 years) : �Development of
Ultrafast Spectroscopy System for Chemistry , Materials Science and Biophysics
Research and Education in the 25-T Split-Coil Helix�
- (PI) NHMF -## (new 2014-2016), �Ultrafast
STEMP Polarization Phase Selective Studies�-
- (PI) NHMF -## (20012-2014), �Ultrafast Polarization Phase Selective Studies�-
- (PI) NHMF -## (2007-2012), �Polarization Phase Selective Studies�-
-Collaborative projects Dr. Brian Hales LSU (2000-2014) and Dr Markus Ribbe
UC Irvine, (NIH GM67626
and NSF funds, BoR, EPSCOR funds) ,
-(DOE, NIH) Collaborative projects at Argonne National Laboratory, Advanced
Photon Source, 2002-present.
- DOE (Co-PI), "A Physico-Chemical Study of Some Areas of Fundamental
Significance to Biophysics" (project
from 1986)
-LEQSF (PI), �Radiation Signatures� (1996)
-Collaboration on science education projects: NSF �Scientific Visualization�
2007-present, NSF �Student retention project�, 2007-present.
Selected
Publications:
1a.
K. Rupnk�, C. C. Lee, Y. Hu, M. W. Ribbe and B. J. Hales, �A VTVH MCD
and EPR Spectroscopic Study of the Biosynthesis of the �Second� Nitrogenase
P-Cluster�, submitted Inorganic Chemistry �, Inorganic Chemistry, 57, 4719
(2018);
1. K Rupnik, C. Lee, J. A. Wiig, Y. Hu, M. W. Ribbe, and B. J. Hales , �Non-Enzymatic Synthesis of the P-Cluster in the Nitrogenase MoFe Protein: Evidence for the Involvement of All Ferrous Intermediates�, Biochemistry, 55 ( 2014) 1108
2. J. Dumke, A. Qureshi, S. Hadman, S. Das, K. Rupnik, B
El-Zahab, D. J. Hayes, I. M. Warner, �Tumor-Targeting Hyperthermal near Infrared
Nano GUMBOS�, Photochem. Photobiol. Sci. (submitted 2014).
3. K. Rupnik PI, �NHMFL
4. K. Rupnik, Y. Hu, C. C. Lee, J. A. Wiig, M. W. Ribbe and
B.J. Hales, �P+ State of Nitrogenase P-Cluster exhibits Electronic Structure of
a [Fe4S4]+ Cluster�, J. Am. Chem. Soc. 134 (
2012) 13749
5. K. Rupnik, C. C. Lee, Y. Hu, M. W. Ribbe, B. J. Hales,
�[4Fe4S]2+ Clusters Exhibit Ground-State Paramagnetism�, J. Am. Chem.
Soc. 133 (2011) 6871.
6. K. Rupnik, Yilin Hu, Aaron W. Fray, Markus Ribbe, and
Brian J. Hales, �VTVH-MCD Spectroscopic Study of
NifEN-Bound precursor�, J. Biol. Inorg. Chem., 16
(2011) 325.
7. T. Brown, Z.
LeJeune, K. Liu, S. Hardin, J-R Li, K. Rupnik, and J. C. Garno, �Automated
scanning probe lithography with n-alkanethiol self assembled monolayers on
Au(111): Application for teaching undergraduate laboratories� , JALA,16 (2)
(2011) 112.
8. D. Shafir, Y. Mairesse, H. J. Worner, K. Rupnik, D.M.
Villeneuve, P. B. Corkum and N. Dudovich, �Probing the symmetry of atomic
wavefunction from the point of view of strong field driven electrons� , New
Journal of Physics 12, 073032 (2010)
9. Marcia S. Cotton, Kresimir Rupnik, Robyn B. Broach,
Yilin Hu, Aaron W. Fay, Markus W. Ribbe and Brian J. Hales VTVH-
10. K. Rupnik PI, �NHMFL
11. R. Broach,
K. Rupnik, M. Ribbe, B, J, Hales, �
12. Uwe Bergmann,
Wolfgang Sturhahn,
Donald E. Linn, Jr.,Francis E. Jenney, Jr., Michael W. W. Adams,
Kresimir Rupnik, Brian J. Hales, Ercan E. Alp, Aaron Mayse, and Stephen P.
Cramer, �Observation of Fe-H/D Modes by Nuclear Resonant Vibrational
Spectroscopy�,J. Am. Chem.
Soc. 125, 4016 (2003)
13. S. P. McGlynn,
P. Brint, J. D. Scott, and K. Rupnik, in "Understanding Chemical Reactivity: The
Role of Rydberg States in Spectroscopy and Photochemistry", edited by C.
Sandorfy, (Kluwier Academic, Norwell, MA, 1999), p. 121.
14. A. Vrancic, K.
Rupnik, L. Klasinc, and S. P. McGlynn, "Time-Resolved Profiles in Modulated
Polarization Spectroscopy", J. Chem. Info. Comput. Sci.
39, 68 (1999).
15. A. Vrancic, K.
Rupnik, and S. P. McGlynn, �A Selective Digital Integrator for
Modulated-Polarization Spectroscopy: An Evaluation using (+)-3
Methylcyclopentanone,� Rev. Sci. Instrum.
69,40(1998).
16. K. Rupnik and
S. P. McGlynn, "The Simulation of an Unusual Magnetic Circular Dichroism
Spectrum: The 5p�
6s Transition of HI", J. Chem. Phys. 103,
7661 (1995).
17. K. Rupnik, U.
Asaf, and S. P. McGlynn, in "Gaseous Dielectrics
18. K. Rupnik, L.
Klasinc, M. Varma, J. Battista, and S. P. McGlynn, "Lesion Spectra: Radiation
Signatures and Biological Gateways", J. Chem. Info. Comput. Sci.
34, 1054 (1994).
19. U. Asaf, K.
Rupnik, G. Reisfeld, and S. P. McGlynn, "Pressure Shifts and Electron Scattering
Lengths in Atomic and Molecular Gases", J. Chem. Phys.
99, 2560 (1993).
20. M. Eckert-Maksic,
Z. B. Maksic, M. Hodoscek, and K. Rupnik, "Inter and Extramolecular
Electrostatic Potentials in Vitamin C", J. Mol. Struct. THEOCHEM, 256, 271
(1992).
21. W. S. Felps,
K. Rupnik, and S. P. McGlynn, "Electronic Spectroscopy of Cyanogen Halides", J.
Phys. Chem. 95, 639 (1991).
22. K. Rupnik, U.
Asaf, and S. P. McGlynn, "Electron Scattering in Dense Atomic and Molecular
gases: An Empirical Correlation of Polarizability and Electron Scattering
Length", J. Chem. Phys. 92, 2303 (1990).
23. K. Rupnik,
"VUV and Laser Raman Study of the Atomic and Molecular Polarizabilities", in
Lasers98, edited by D. G. Harris, (
24. R. G. Parr, K.
Rupnik and S. Gosh, "Phase-Space Approach to the Density Functional Calculation
of