After a novel composition
is synthesized, the next steps are evaluation of its performance and analytical characterization. On the
one hand, we need to know if the material is useful (performance), and the on the other, what it is (characterization).
At Aquero, the compositions are analyzed using a set of standard measures, a few of which are described below.
In addition, for some specialized assessments, we either send out samples or obtain a particular instrument
for a set time on a rental or lease basis.
Typical assays using this instrument are phosphate analysis, free-amine content (ninhydrin reaction), characteristic
spectral signature (specific peaks corresponding to specific groups), dispersion assays, and others.
|Fourier transform infrared spectrometer
transform infrared spectrometer)
Infrared spectra are measured with this instrument. The presence
or absence of particular groups and compounds can be shown this way. Polyamino acids, polysaccharides, proteins, their
combinations, and an array of other compositions can be detected, at least qualitatively, via their IR signals.
|High performance liquid chromatography system
HPLC (High performance liquid chromatography)
The LC is a workhorse that is used for several purposes. For example, molecular size of novel compositions can
be assigned based on comparisons of their elution profiles to those of standard molecules when run through
gel permeation columns. Consumption (disappearance of certain peaks) of reactants and formation of desired products
(appearance of certain peaks) can be followed. Concentrations of compounds by peak height or area are frequently
assessed. Presence (peak position) and concentrations (peak magnitude) of ionic solutes can
be measured via conductivity detector and ion-exchange columns.
In some cases, molecules can be
detected via their natural fluorescence in solution or in an extract, for example, of soil or oily solids.
We also have developed specific fluorescent markers for following the deployment of our treatment chemicals in agricultural
and oil-recovery applications. Such fluorescent markers can be arranged to be very sensitive, allowing measurments of
extremely low levels of target molecules. This enables us to track them at great dilutions or distances from
the point of their introduction into an irrigation stream or an industrial process stream.
There almost always is a viscometer somewhere in a laboratory where polymers are studied. One of the main reasons
for this is that molecular weight of very large molecules (Mw's well into the millions and tens of millions and higher)
is hard to know. Historically, the only decent approach to estimating Mw of very large polymers was based on their viscosity
in solution, larger molecules tending to generate higher viscosities in solution. This is still a standard approach,
among a variety of other approaches, to assignment of molecular size of polymers. Viscosity measurements are also useful
to know in designing reaction processes for larger scale synthesis and manufacturing of some compositions.