LOGO2

Applications of the conductivity method

 

Can be applied to any chemical change where there is a change in ionic composition as a result of the reaction - this is explained in detail in the Introduction

 

 

BLOOD & URINE TESTS - which can be done using this method? - see list below

The method can be applied to most enzyme-catalysed reactions. The apparatus & methods presented on this site overcome the drawbacks that have prevented this method from being more widely used in the past.

 

Reactions that are easily measured are:

 

KINASES/ATP'ases

 

PHOSPHATASES

 

HYDROLASES [not amylase & friends]

 

PEPTIDASES/PROTEINASES

 

ESTERASES/LIPASES

 

MOST OXIDASES

 

More difficult would be DEHYDROGENASES, although there is no change in the number of ions there is a change in mobility of the ions, [e.g. from NADH to a proton], so this may well be measurable. Spectroscopy will remain the favourite method for these enzymes I think.

 

ISOMERASES look unsuitable for this method

 

The technique is easy to use and could be applied for clinical tests [with the exception of glucose, which has been 'solved with inexpensive miniaturised sensors aand readout systems - brilliant!!

 

The same technology could easily be applied to more generalised measurements of the enzymes described above. The main problem I forsee is the shrinking of the temperature control system which needs to be accurate for the measurement of rates of reaction. The enzyme can be added as a reaction component or, as in the glucose detectors, be attached to the electrode surface, so that only the substrate and buffer need to be added.

 

The apparatue as presented here is ideal for school/ college research projects & it could be commercialised using modern minitiaturisation methods for widespread use in CLINICAL TESTING, not only in a lab setting but most importantly in the FIELD, since it is easily transportable, e.g. on a bicycle.

 

HAVE A GO YOU WILL FIND IT FUN!

 

 

CLINICAL TESTS FOR BLOOD USING THE CONDUCTIVITY METHOD

 

 

Urea                                               XXX

Creatine kinase                              XX

Lactate Dehydrogenase                 X

Nucleotidase                                   X

Alkaline phosphatase                     XX

Angiotensin Conv. Enzyme            XX

 

Number of X's indicates sensitivity, assessment is based on ionic (& mobility) change upon reaction. Glucose is excluded as excellent inexpensive kit is available.