500: $11/hour including cryoprobe
The 500 is driven by an automatic sample
changer. Seven standard experiments make up the great majority of
what it does. The default parameters for those experiments and
corresponding costs are (daytime rates with cryoprobe):
Experiment # scans time cost @$11/hr
Proton 16 1:05 $0.20
Carbon 1024 22:25 $4.10
DEPT-135 256 13:40 $2.50
COSY 1x256 5:45 $1.05
HSQC 2x256 18:40 $3.42
HMBC 8x128 23:04 $4.23
NOESY 2x256 21:20 $3.91
The number of scans on the
1D's can be increased or decreased to any value; the 2D's typically
cannot advantageously be
made shorter (i.e. it either won't work at all, or the level of
artifacts is likely to be higher). What constitutes enough scans for a
particular sample depends on the amount of compound, the amount of
solvent (an excess will dilute the sample and make the results worse),
and what level of signal to noise you think is appropriate.
I think it is a very good idea to get a proton spectrum of everything submitted on the 500 because it is very indicative of the integrity and concentration of the sample, if nothing else. If you are concerned about the 20 cents, we can shorten another experiment by 16 scans.
The most important thing
you can do to get the highest quality results in the shortest time
and at the lowest cost is to restrict the amount of solvent used to
0.5-0.6 ml. Less than that may hurt resolution. Increasing the
number of scans on a run is a very cost-inefficient way of making up
for an excessively diluted sample, because the signal to noise will
only increase with the square root of the number of scans. If you
want to double the S/N, you must make the acquisition 4 times longer
(and 4 times as expensive).
You can have an email notification of
your sample being run on the 500, with a PDF file of the plot as an
attachment. Let us know if you prefer this. It is also
possible to have the raw data emailed to you, although these
attachments are larger than the PDF plot files.
The Avance 400 is the most restricted instrument. Prime time runs from 8:30 am to 8 pm weekdays, and signup is not permitted until 4 pm the previous day. From 9:30 am-3pm, no user can reserve, or use (no matter who reserved the time) more than 30 minutes, either in one block or multiple blocks. From 8:30-9:30 am and from 3-8 pm, the maximum is one hour. Users may have both a one hour block and a half hour block in the same day, for a total of 90 minutes maximum. On Saturday and Sunday, the maximum length is 1 hour between 9 am and 5 pm. In the evening (after 8 on weekdays and after 5 on weekends) there are no restrictions on the length of an experiment and users can sign up as many as seven days in advance.
On the Higuchi and LSRL 400, the weekday limit is 6 hours
per person per day between 8 am and 5 pm. Other times are
unrestricted. Since the LSRL instrument is owned by the CMLD, they have
priority when they need it.
The Avance 500 runs by automation, so there is no signup per
off your sample and it's first come, first served.
Hands-on use of the Inova 600 and Avance
800 are restricted to those users approved by the NMR
Lab staff. Anyone can get data from these instruments on a service
basis on request. Long experiments have priority over short ones at all
times. The instrument calendar is kept online at http://kunmr7.chem.ku.edu/cgi-bin/nmr-schedule.cgi.