Q-Dots or other high yield fluorophore that exite at ~254nm and emit at ~300nm?

More Yoram Gerchman's questions See All

Separation of Cholesteryl esters from alkanes/alkenes?

Greetings We are trying to study Cholesteryl esters. We start with MeOH/Chloroform extraction and then remove most of the noise by silica column, but the Cholesteryl esters come out with...

02 June 2024 5,545 0 View

EcoRV resistance E. coli?

Greetings I am working with a plasmid encoding the restriction enzyme EcoRV. Do you know of E. coli strain resistance to EcoRV restriction?

06 January 2024 8,223 4 View

"Tryptone" peptide ans casamino acids - are they phosphorylated?

Greetings all. As you probably know the "Tryptone" used as component of LB media and alike are the product of digestion of casein. Similarly Cas-Amino acids are the product of acidic hydrolysis of...

09 January 2022 2,002 1 View

Help in using MG-RAST database ?

Greetings all I am looking for a way to search for specific gene(s) expression levels in an environmental transcriptome data posted on MG-RAST. If anyone has expertise in doing such it would be...

09 May 2020 2,581 0 View

Comercial "stratum corneum substitute" lipid mixture?

Greetings We want to look at the effect of Stratum Corneum composition on bacterial attachment. Does anyone know a commercially available "stratum corneum substitute" lipid mixture? Or is willing...

17 November 2019 1,539 2 View

Extraction of Heme A, Heme B and Heme O?

Greetings I am looking for a trusted protocol for extraction of Heme A, Heme B and Heme O, to be used as standards in HPLC analysis. Alternatively if you know of a commercial source also...

27 May 2019 5,398 2 View

Origin of 220nm absorbance peak of free amino acids?

Greetings I am trying to find out what is the origin of the 220nm absorbance peak of free amino acids? It is usually attributed to peptide bond but I find it also in single aa... Yoram

17 June 2018 5,773 3 View

Fluorophore with excitation at the UVC range and emission in the visible range?

Greetings all I am looking for a fluorophore with excitation at the UVC range (250~260nm) and emission in the UVA/visible range. Ideally one that will not bleach easily. Many thanks Yoram

05 March 2018 1,528 0 View

Energetic cost of biomass pretreatment (especialy steam explosion)?

Greetings I’m looking for numbers (rather then general statments) on the energetic cost of different biomass pretreatments before enzyme digestion for sugar release. I am especialy intrested in...

28 January 2018 5,810 5 View

Can I connect HP1047A RI detector to Agilent 1200 HPLC system?

Greetings We need to buy an RI detector for our Agilent 1200 HPLC system (connected to a computer running ChemStation). Given the high price of new detector I thought about buying a used one....

19 October 2017 6,463 9 View

Hello researchers Is this a random laser or just fluorescence?

I am using Rhodamine6G as gain medium and silver nanoparticles as scatterers on a microscope slide and laser input 532 nm comes from above.

09 August 2024 9,894 2 View

Weak DAPI staining after immunohistochemistry - how to improve?

After immunohistochemistry of previously fixed in PFA and EtOH and then frozen 20 μm sections of zebrafish brain, DAPI staining is very weak (right) compared to the same sections stained without...

05 August 2024 9,637 2 View

If we are using snowball sampling technique, how do we justify the true representativeness of the sample statistically? is there any statistical test?

Are there any statistical methods to justify your sampling technique using SPSS or AMOS?

05 August 2024 9,153 4 View

Are there any commercially available Donkey anti-Alpaca secondary antibodies?

Are there any fluorescently labeled anti-Alpaca secondary antibodies raised in Donkey? So far I have only been able to find anti-Alpaca secondaries raised in Goat. Or is this not possible due to...

04 August 2024 4,255 1 View

What are possible strategies can be used to analyze data under sequential explanatory mixed method approach?

Better ways to analyze the qualitative and quantitative data in a sequential explanatory mixed method approaches

04 August 2024 2,703 6 View

Why results of ROS flurescence are negative as there was no bacteria within?

Hello. I am working on ROS production of two systems: system A is cerium oxide and hydrogen peroxide, system B is cerium oxide nanoparticle, hydrogen peroxide and potassium bromide. I did some...

04 August 2024 5,974 3 View

How to calculate the molar proportions of the oxides from the XRF analyses?

02 August 2024 2,565 2 View

Why 3 replicates for most biological assays? Is it enough to examine the data fits normal distribution?

Just bounced on me. Before statistically analysing significant difference, shouldn't we see if data fits normal distribution first? Is 3 replicates enough to testify the hypothesis of normal...

31 July 2024 8,141 13 View

Request for Advice: Starch Metabolism Research Project?

I am currently considering a research project focusing on a comparative analysis of starch metabolism in orchids and roses. I am particularly interested in identifying the types and quantities of...

30 July 2024 4,267 2 View

Can the limit of quantification (LOQ) of an analytical method fall outside its linear dynamic range, or must it always be within it?

Can an analytical method's limit of quantification (LOQ) be outside its linear dynamic range, or is it always required to be within it? Please provide a thorough explanation supported by verified...

29 July 2024 7,198 9 View

Ofir Tal

Sounds like Tyrosines abs and emission. Although I'm not sure regarding the q.y..

Fabrizio Messina

Tyrosine QY is very low. PTP is indeed a good suggestion (you can solve it in methanol or ethanol in reasonable concentration). If 350 nm emission still works, another alternative is 2,5-Diphenyloxazole..