Why could be there a redshift of emission peak of a dried fluorescent dye as compared to the solution?

05 May 2018 1 7K Report

A fluorescent dye has emission peak at 575 in aquous solution but is shifted to 615 upon drying. what could be possible reasons?

Tuhin Khan

Are you talking of emission spectra of dried solid sample? In a concentrated phase aggregation could take place which could be responsible for red shift (J-aggregates).

https://www.researchgate.net/post/What_are_the_characteristics_of_J-aggregate_in_fluorescence

More than that in concentrated phase inner filter effect (reabsoprtion of emitted light) could take place which would result in "red shift" in peak. Please read Lakowicz's book on secondary inner filter effect (Principles of Fluorescence Spectroscopy). In a recent paper we have also shown how in solid phase secondary inner filter effect may result in "red shift" and how to minimize it.

http://www.currentscience.ac.in/php/forthcoming/27086.pdf

Badges
Science topic

More Rashmi Shrivastava's questions See All

The transfected cells are showing very weak mcherry fluorescence. How to detect mcherry expression?

The animal cells are transfected with a vector having mcherry reporter gene. The transfected cells show very weak fluorescence. How to get a good quality fluorescener image showing mcherry...

07 August 2018 7,498 3 View

Which cloning cylinders are best for isolating cell colonies? Glass or pyrex?

For isolating cell colonies cloning cylinders made of glass or pyrex are most easy to handle and preferred?

31 December 2017 4,934 6 View

Which is the most efficient method of transfection of Min6 cell lines with circular plasmid? Calcium phosphate/lipofectamine/electroporation or other?

I want to stably transfect Min6 cell lines with ciruclar plasmid . Kindly suggest which method is the most efficient.

31 December 2017 9,333 2 View

How to preserve stably transfected animal cell lines?

Can stably transfected cell lines be cryo preserved using general preservation protocol?

31 December 2017 6,560 5 View

Which laser suitable for activation of ChR2 protein in mammalian cells?

Which laser is most suitable for optogenetic activation of ChR2 in non-neuronal mammalian cells. What power range is required?

31 December 2016 8,618 4 View

Sources for Optogenetic ChR2 mammalian expression vectors?

I am interested to get ChR2 mammalian expression vectors. Please tell what are the sources I can get hese from. One I know is Addgene. Kindly inform if there are any other too...

11 December 2016 962 1 View

What precautions and safety guidelines to be followed for staining samples with Uranyl acetate for TEM?

What precautins to be taken and how to discard the material stained with uranyl acetate safely?

10 November 2016 9,634 7 View

How can cell lines be ordered from SIGMA?

I want some cell lines from SIGMA, but their online lists just shows about the DNA , cDNA or RNA of the respective cell line. How can I order the cells in culture?

10 November 2016 5,882 2 View

Can optogenetic vectors be shuttled between bacteria and mammalian cells ?

09 October 2016 3,267 1 View

Please provide a reference for thermal conductivity of polystyrene sulfonate?

I need to know the thermal conductivity of polystyrene sulfonate.

03 April 2016 4,546 1 View

New Journal, "Integrative Psychological and Behavioral Science" -- do you not know, and have you not seen, this done before?

Question to you and THEM, the New Journal, "Integrative Psychological and Behavioral Science" -- do you not know, and have you not seen, this done before? There appears to be a core problem for...

02 March 2021 3,024 2 View

Does any one can help me choose a reasonable basis set for intermediate metal ions interactions with guanine (i.e Fe2+, Mn2+, Cu2+ and exc.)?

Hello every body Does any one has any idea to help me choose a reasonable basis set for intermediate metal ions (i.e Fe2+, Mn2+, Cu2+ and exc.) interactions with guanine or other DNA organic...

01 March 2021 6,187 2 View

What could be some reasons why unstimulated monocytes are getting activated?

Im doing PBMC isolation -> CD14+ enrichment using magnetic beads -> stimulation setup. My negative control is just cells in cRPMI but they seem to get activated over and over again.

28 February 2021 7,883 3 View

Why does intensity drops as concentration increases?

Is there any reason for decrease in fluorescence emission intensity of HSA,BSA when increase the concentration ?

28 February 2021 3,653 4 View

POlymer+DMSO solution and moisture??

What could be the reason of moisture at the sides of Vial when I am preparing my polmyer+DMSO solution for membrane fabrication? What etiquettes I am possibly missing here?

28 February 2021 6,516 5 View

Should we reduce the standard unit of length to 0.31951540592 meter ?

The reasoning behind this question is to align the ratios of the proton potential in energy per charge to the speed of light in distance per time. As these two dimensions appear to be related,...

27 February 2021 947 7 View

What could be reason for getting such type of graph for complex impedance in case of polymer blend films?

Its effect appears in real part of ac conductivity also. Can anyone suggest any reason behind it?

26 February 2021 3,487 3 View

Is IMPACT FACTOR justified in case of Taxonomy?

There is huge pressure of getting good impact factor on scholars now a days. On the other hand Taxonomy is a very dry subject and the concerned papers can only get citation in same group of organism.

26 February 2021 5,851 1 View

Uncertianiny in using dry or wet basis in mixing a sediment with fuel oil?

Hello I'm currently working on a topic related to studying the anaerobic biodegradation of TPH in marine sediments. In this work, sediment should be mixed with fuel oil to a concentration of 20 g...

24 February 2021 9,839 3 View

Standard curve shifting over time. How do I stabilise the ELISA?

24 February 2021 1,365 3 View