A New Interpretation of the Absorption and the Dual Fluorescence of Prodan in Solution

Prodan is a fluorescent probe used to monitor biological systems such as lipid membrane,<br>proteins and DNA. Remarkable interest is associated to the interpretation of its fluorescent spectrum.<br>In this paper the sequential hybrid Quantum Mechanics/Molecular Mechanics (S-QM/MM) method was used to establish that the fluorescent emission occurs from two different excited states, resulting in a broad asymmetric emission spectrum with two transitions. The absorption spectra in several solvents were measured and calculated using different theoretical models and they all agree that the first observed band is composed of three electronic excitation very close energetically to each other.

A New Interpretation of the Absorption and the Dual Fluorescence of Prodan in Solution

Prodan is a fluorescent probe used to monitor biological systems such as lipid membrane,<br>proteins and DNA. Remarkable interest is associated to the interpretation of its fluorescent spectrum.<br>In this paper the sequential hybrid Quantum Mechanics/Molecular Mechanics (S-QM/MM) method was used to establish that the fluorescent emission occurs from two different excited states, resulting in a broad asymmetric emission spectrum with two transitions. The absorption spectra in several solvents were measured and calculated using different theoretical models and they all agree that the first observed band is composed of three electronic excitation very close energetically to each other.

A New Interpretation of the Absorption and the Dual Fluorescence of Prodan in Solution

Prodan is a fluorescent probe used to monitor biological systems such as lipid membrane,<br>proteins and DNA. Remarkable interest is associated to the interpretation of its fluorescent spectrum.<br>In this paper the sequential hybrid Quantum Mechanics/Molecular Mechanics (S-QM/MM) method was used to establish that the fluorescent emission occurs from two different excited states, resulting in a broad asymmetric emission spectrum with two transitions. The absorption spectra in several solvents were measured and calculated using different theoretical models and they all agree that the first observed band is composed of three electronic excitation very close energetically to each other.

Time Machine: Can a Dye from 1928 be Re-Purposed for Modern, Fluorescence-Based Detection of Amyloid-Like Fibrils?

This manuscript describes the chemical synthesis of a compound similar to fluorene and Congo red, including characterization of its spectral properties. It was shown that the dye, during interaction with amyloid-like fibrils of several proteins (lysozyme, insulin, and beta-2-microglobulin), has the ability to change fluorescent spectrum. In contrast, monomeric forms of these proteins did not induce significant spectral changes.

Synthesis of Furan-Substituted N-Heteroacene-Based Liquid Material and Its Acid-Recognizing Behavior

In this study, we synthesized a novel N-heteroacene-based liquid material 6,7-bis(3,7,11-trimethyl-1-dodecyloxy)-2,3-difurylquinoxaline (RPNL 1), containing two furan rings. We revealed that RPNL 1 adopted a disordered liquid at 25 ∘ C, determined by polarized optical microscopic observation, differential scanning calorimetry, and X-ray diffraction measurements. The fluorescent spectrum measurement revealed that RPNL 1 showed a blue emission at 25 ∘ C. Dissolving benzene sulfonic acid (BSA) in RPNL 1 brought about dramatic changes in its physical properties, such as emission colors, as well as sample states. Upon recognizing BSA, photoluminescent color was changed into orange, as well as phase transition occurred from liquid to a liquid-crystalline phase. RPNL 1 can function as an acid-recognizing material, accompanied with the color changes in emission.

Optical Properties of Laser Lines and Fluorescent Spectrum in Cholesteric Liquid Crystal Laser

We experimentally studied the comprehensive optical properties of the laser lines and fluorescent spectrum generated by a continuous tunable cholesteric liquid crystal (CLC) laser array. We found that the laser lines generated from a CLC with a right-handed circular helix were right-handed circular polarized and laser lines generated from a CLC with a left-handed circular helix were left-handed circular polarized. Inside the photonic band gap, the CLC structure with right-(left-) handed helicity suppressed the fluorescence generated with right (left) circular polarized light, and instead the suppressed right (left) circular polarized light energy moved to the outside of the photonic band gap, so we can say that the fluorescence intensity outside of the photonic band gap is enhanced with right (left) handed circular polarized light. Depending on the position of the photonic band gap, the fluorescence quantum yield value increased by up to ∼15%. These enhanced fluorescence intensities at the PBG edge will evolve into lasing at the upper lasing threshold. It is particularly interesting to see that the fluorescence intensity and shape could be controlled by adjusting the external geometrical factor of the photonic band gaps. The lasing threshold of the CLC lasers was in the range of 1.5–5.3 μJ/pulse. For CLC laser device applications, it is necessary and essential to know the optical properties of the generated laser lines and of the fluorescence spectrum.

Transient spectrum of sin2-pulsed driven harmonic oscillator

Exact analytical results are derived for the coupled system of nondissipative single mode quantized harmonic oscillator (HO) and arbitrary pulse shape. Specifically, for a sin2-pulse shape, the transient fluorescent spectrum is obtained in the general case of initial coherent state |α〉 of the HO. The dominant central Lorentzian is surrounded by weak oscillations due to the larger number of sequential pulses which get amplified asymmetrically in the nonresonant case as a result of balancing and interference processes between the initial excitation (|α2|) and the strength of the exciting pulse. Further pronounced oscillations is noticed with "hole burning" structure in the central peak due to nonzero phase of the initial amplitude (α).

Design of X-Ray Fluorescence Spectrum Software Based on Linux

According to the research on analysis software of X fluorescent spectrum under the Linux system, a new algorithm of X fluorescence analyzer has been brought up: use the method of energy dispersive X fluorescence analysis, based on the software that can analyze the material composition under the control of ARM - Linux touch screen. This paper fixes on developing software of X fluorescence analyzer; realize the collection and analysis of multi-channel spectrum data, data storage, sample analysis, qualitative and quantitative analysis of the on-site samples, and the research and implementation of corresponding algorithm.