Carbon sponges New carbon sponges created by UK scientists using a molecular moulding approach could be used to selectively absorb specific gases. The geometry of the pores of the new materials has been precisely controlled at the nanometer scale by Tim Mays of Bath, Nigel Seaton of Edinburgh and Geoff Moggridge of Cambridge Universities.
Alzheimer's clue Canadian researchers have excised another clue as to the cause of the debilitating brain disorder Alzheimer's disease. The discovery might one day lead to a new class of drug that blocks the build up the beta-amyloid-peptide in the brain that leads to progressive memory loss, speech problems, delusions and immobility.
Two-faced molecule offers NO explanation A Janus molecule isolated from a soil bacterium could help explain the regulation of blood clotting and the male erection, according to a team at the John Innes Centre in Norwich (JIC). The hemoprotein cytochrome c' (cyt c') from the denitrifying soil microbe Alcaligenes xylosoxidans has a strong affinity for the neurotransmitter nitric oxide (NO), which it binds in a novel and unexpected fashion.
Addiction and drugs Ondansetron a drug used to prevent nausea in cancer chemotherapy patients might, according to US researchers, lead to a new way to treat alcoholism.
||Reactive Science News
See the presentation
A Comprehensive Method Development and Management System Incorporating Chemical Structures by
Michael McBrien, Eduard Kolovanov, and Antony Williams (ACD/Labs).
See the presentation
A Molecular Structure Based System for LC Simulation by
Michael McBrien, Antony Williams and Eduard Kolovanov (ACD/Labs).
ACD/HPLC Simulator allows you to input one or more chemical structures and
then predict the relative retention times on a high performance liquid
chromatography column. If experimental data are known for some of the
structures, the accuracy of the predictions can be significantly improved
through system training. LogD, the octanol/water partition coefficient for
dissociative systems, is the crucial component in the prediction of the
retention times of different compounds in reversed phase HPLC and ion
exchange HPLC analyses. For large structures
containing more than 10 acidic protons the logP values (the octanol/water
partition coefficient for neutral forms) instead of logD values are used.
ACD/HPLC Simulator allows the user to input the experimental values of
retention time for any set of three or more structures and obtain the
prediction equation. Using this equation, the
program predicts the retention time for any new structure under the
experimental conditions. It also allows the user to calibrate a column using
the Conditional Charge coefficient without entering the experimental
retention times. Furthermore, the obtained calibration can be used for the
prediction of the elution order for any set of structures. Continue...
Harry G.Brittain, Ph.D. (Center for Pharmaceutical Physics, Milford, NJ, USA):
Use of the ACD/PhysChem during the
Preliminary-Preformulation Program of Drug Development
It is generally understood that the goal of a preformulation study is to obtain sufficient information on a proposed chemical entity that permits its formulation into a stable dosage form capable of delivering the substance for its intended use. Highly important at this stage is knowledge of the compound ionization constant(s), its solubility and partition characteristics, pH dependence of aqueous solubility, pH dependence of partition coefficients, and solubility in non-aqueous systems). In the usual practice, these are empirically determined once the Preformulation Group receives a sufficient quantity of the substance, and the information they obtain is used to deduce crystallization conditions for generation of the most stable solid form of the proposed chemical entity.
Snapshots of Celebrity Molecules
If you are working on a fascinating formulation or a marvellous material, or perhaps you think your compound is simply cool, then tell us about it and visit our Gallery of Celebrity Molecules.
ACD/Labs Scholar of the Year 2000 Award