Molecular Rotor Measures Viscosity of Live Cells

Anant Babu Marahatta
Tohoku University, Japan (ananta037@gmail.com)

Introduction:Viscosity is one of the major parameters determining the diffusion rate of species in condensed media. In bio-systems, changes in viscosity have been linked to disease and malfunction at the cellular level. These perturbations are caused by changes in mobility of chemicals within the cell, influencing signaling and transport and the efficiency of bimolecular processes.

Observation:

Fluorescence measurements of 1 made in methanol/glycerol mixtures of different viscosities shows that the fluorescence quantum yield increases dramatically with increasing solvent viscosity.The observed increase in fluorescence intensity is consistent with the restricted rotation of the phenyl group in the medium of high viscosity. The rates of radiative and nonradiative decays have been calculated from the measured fluorescence lifetimes and quantum yields. From these results, it has been concluded that, for 1, the nonradiative decay rate increases with decreasing viscosity, and the radiative decay rate remains approximately constant. Thus 1 is truly a molecular rotor which displays both fluorescence intensity and lifetime sensitivity to viscosity of the environment.

For detail, readers are requested to go through J.AM.CHEM.SOC. 2008,130, 6672-6673 if interested.

Chemistry Jokes: Fun Chemistry

1. Why do chemists call He, Cm and Ba the medical elements? >>>>Because if you can’t helium or curium, you barium.
2. What do you do with a dead chemist? >>>>Barium.
3. Two atoms bump into each other.’I think I lost an electron.’ The other asks: ‘Are you sure?’ The first replies: ‘I’m positive.’
4. What did the chemist say when he found two isotopes of Helium? >>>>>>>‘HeHe’
5. Gold walks into a bar, barman shouts Au get out of here!
6. Why did the white bear dissolve in water? >>>>>>>>>Because it was polar
7. Last night a hypnotist convinced me I was a soft, malleable metal with an atomic number of 82. >>>>>I’m easily lead.
8. Are you familiar with Friedel-Crafts? Sure, it’s by the Hobby Lobby on Route 3.
9. What weapon can you make from the chemicals potassium, nickel and iron? >>>A: KNiFe
10. Billy was a chemists son but billy is no more. what billy thought was H₂O was H₂SO₄.
11. 2 men walk into a bar, the first orders some H₂O. The 2nd one says ’sounds good, i’ll have some H₂O too’. The 2nd man died.
12. Some guy tried to sell me sand for a thousand bucks yesterday. >>>>It was such a silicon.
13. What do chemists use to make guacamole? >>>>Avogadros.
14. I like making bad chemistryjokes because all the good ones Argon
15. How much is a glass of Adenosine TriPhospate? >>>80p.
16. What do you call a tooth suspended in 1 litre of water? >>>>A Molar solution.
17. A photon checks into a hotel and is asked if he needs any help with his luggage.>>>>”No, I’m travelling light.”
18. Chemical jokes are boron… however physics jokes have potential.

Laser Tweezers to Detect Single Nucleotide Polymorphism

Scientists in the Department of Chemistry, Kent State University have introduced a new novel method to detect Single Nucleotide Polymorphism (SNP) using laser tweezers in microfluidic platform. This work has been published in Journal of the American chemical society (JACS), a leading journal in Chemistry.

SNP is the most common variation in the genomic DNA sequence between members of the same species by one nucleotide. This is caused by various factors. Studies have revealed that they are distributed throughout the human genome by an estimated average of 1 per 1000 base pairs. SNPs are attributed to be closely linked with gene function, genetic variations between individuals, variety of diseases and susceptibilities of humans to the pathogens. Usually SNP is not associated with any disease but it might cause variation in response for the disease, toxins, bacteria, drugs etc. They may be used as bio-markers for disease genes. And, it definitely requires reliable method.

SNPs can be detected by several methods such as molecular beacons, gene sequenceing or some other analytical tools that can detect the difference in effect of a single nucleotide in base pairing with the complementary DNA. The novel idea in the above mentioned publication is the incorporation of the mechanical differentiation of the base pairing event with the microfluidics platform and is expected to be useful in the development of generic biosensors. Laser tweezer was used to monitor the binding of the target DNA sequences with the probe molecule, a DNA hairpin. Binding of the target with the hairpin DNA tied to the tweezers caused hairpin molecule in the unfolded (off) state instead of the stochastic hopping between folded(on ) and unfolded (off) states. Authors had claimed that this method has less background signal compared to fluorescence based technique and easier compared to the PCR based amplification and sequencing techniques. This method has been sensitive enough to detect 100 pM SNP associated with the coronary heart disease.

According to Deepak Koirala, chemistry graduate student and main author of the article who came from Nepal, this innovation is in the process of getting US patent.

International Collaboration in Science

Anant Marahatta, Doctoral Student (Chemistry)
Tohoku University, Japan
(ananta037@gmail.com)
(Relevant to my collaboration with Germany)
The general meaning of an “international collaboration in science” is explained by these advanced words: global science, global networks, global co-authorships, global interaction, global conference, global sharing, and spreading global hand for helping on different disciplines of science and technologies etc.

Though there is no political institution organizing the sciences on an international level, a self-organized, global network had formed in the late 20th century. It has been found that international collaborations are being doubled from 1990 to 2005. While collaborative authorships within nations have also risen.

This is the century of getting revolution in the world due to the different fields of sciences. If the researchers and scientists of any well developed countries have proudly announced that they are eligible enough to carry out any sorts of revolutionary changes in the field of science, they have initiated to deteriorate their countries themselves. So for getting several supports and ideas, all the countries if possible must be the member of the international collaboration. Any one can analyze that, international collaboration improves all the countries of the world by applying a range of tools including social network analysis and factor analysis, to expose the network.

There has been a rapidly growing literature discussing the increase in international linkages in science. Authors have been approaching the questions from three perspectives: 1) scientific analysis of the increase in the interconnectedness. 2) Social sciences analysis of collaboration in general and international linkages in particular and 3) policy analysis of the implications of linkages for funding and outcomes. The increase in investment in research and development from governments and non-governmental organizations (such as the World Bank) is for using science as a tool to aid development and for contributing to the diffusion of capacity into the collaborating countries. Scientific collaboration may lead to a range of outcomes such as publication of co-authored articles is one of these outputs.

Collaboration in the technology sector refers to a wide variety of tools that enable groups of people to work together. Collaboration encompasses both asynchronous and synchronous methods of communication and serves as an umbrella-term for a wide variety of software packages. Perhaps the most commonly associated form of synchronous collaboration is web conference using tools such as WebEX or Microsoft Live Meeting but the term can easily be applied to instant messaging as well.

According to the available information, at the global level, the network of interactions is shown to be very strong and highly interconnected. Above figure illustrates the association of all the countries of the world in 2000. The main point is that science is a highly interconnected network, with a dense core and a number of periphery countries.

Thus international collaboration seems one of the important tools for making revolutionary change in the world by developing and introducing the multidisciplinary fields.