Sunday, June 19, 2011

Click chemistry in RNA - marrying Uridine and Azidocoumarin

Marrying Uridine and Azidocoumarin provided a multifunctional sensing moiety in RNA which allows photoaffinity labeling and click chemistry. The key elements are summarized in the drawing below.
Mark Helm et al, Nucleic Acids Research, doi:10.1093/nar/gkr449 published June 6, 2011



Sunday, June 12, 2011

Click chemistry Now and Then

Click chemistry "now and then" by numbers

No intention to be exclusive or "scientific", this is to perform a simple "statistical" count on click chemistry application in different areas . A "historical" view is provided by comparing two periods, 1999-2007 for "then" and 2011 ( Jan 1 - June 12) for "now". The data for the first period was from Sharpless laboratory's compilation of click chemistry (937 articles). The data for the second period was from a Chemical Abstract search (525 articles). 

Published articles titles were searched by selected key words and the counts are recorded as a simplified reflection of research intensity or trend. The format is "key word / number from 1st period / number from 2nd period.   

click /415/308
click chemistry /262/178
poly- /389/371
polymer /173/253
dendrimer /37/15
material /17/52
dye /2/6
fluorescence & fluorescent / 12/14
cyclodextrin /4/12
drug /26/21
inhibitor /34/25
enzyme /16/6
screen /9/3
combinatorial /10/1
Sharpless /105/1
Huisgen /22/3
synthesis /315/150
cycloaddition /121/24
nano /51/71
epoxide /9/0
triazole /129/47
Diels-Alder /12/2
water /34/9
ligation /21/5
conjugate /49/46
bioconjugate /16/21
oligo /26/16
DNA /24/18
protein /48/29
peptide /51/32
glyco /64/53
sugar /7/7

The first period was roughly the rising and maturation of click chemistry over a few years (937) while the second is the application of click chemistry in many fields in merely half a year (525). Although to obvious dissatisfaction of statisticians it is safe to conclude that click chemistry is much more widely used now than then.  
                                                       

Sunday, June 5, 2011

Large Stokes Shift Dyes for Click Chemistry Applications

Large Stokes Shift Dyes feature a large separation between absorption and emission and allow unique advantages for  multiplexing, FRET and other applications. This is to summarize a few large Stokes shift dyes from recent literature and vendors, including several large Stokes shift dyes carried by Sigma-Aldrich for click chemistry applications. Synthetic or natural polymers and nano particles are not included.