GM7 Micro-Stat
A research analyser with a unique assay menu including:
Glucose, Lactate, Cholesterol, Alcohol, Acetoacetate, Urate, Urea, Pyruvate, Glutamine, Ammonia, Creatinine,
3-Hydroxybutyrate, Glycerol
and Triglycerides.

Download GM7 pdf Brochure 

Major Application Areas:

Diabetes Research Studies
All the important parameters i.e. glucose, 3-hydroxybutyrate, acetoacetate, and lactate can now be made on one desktop analyser. The small sample size and fast time to result make the analyser ideal for glucose research studies. Manual calibration ensures that the reagent is not wasted and avoids 'lock out' at critical moments which is characteristic of instruments with automatic calibration.

Clinical Research
The unique analysis menu in the GM7 enables researchers to undertake metabolite studies of analytes not normally available even on much larger multichannel instruments many times more expensive. Analytical parameters are controlled via the keyboard to optimise measurement conditions for special concentration ranges.

Biochemical Research
The analyser incorporates two user-definable assay options which can be used for studies on either novel oxidase or dehydrogenase enzyme systems. A reagent kit is also available to monitor NADH produced or consumed in cofactor linked reactions.
 

Analytical Principle:

In oxidase enzyme reactions, the analyser measures the rate of oxygen uptake and under appropriate controlled conditions, this is directly proportional to the concentration of the analyte.

Example: Lactate in whole blood or plasma:   
 

Substrates for dehydrogenase enzymes are measured using two stage reactions in which the oxidation of NADH (produced or consumed) is monitored.

Example: Ammonia in plasma - Ammonia is converted to L-glutamate with a-ketoglutarate in the presence of glutamate dehydrogenase (GLDH) and excess NADH in a brief pre-reaction:

Stage 1:

Under the conditions of the assay, the rate of oxidation of excess NADH by peroxidase (POD) is inversely proportional to ammonia concentration:

Stage 2:

Operation:

For many assays, injection of sample is all that is needed to obtain a result and prepare the analyser for the next analysis. Sample injection via an accurate positive displacement pipette triggers the complete analytical cycle and a hard-copy result is printed within 20 seconds. The analyser is first calibrated with a standard of the metabolite in question.
Samples can be whole blood (for key assays such as lactate, glucose, urea), plasma, serum or other biological fluids.
Analyses are menu-driven via the 32-character display which guides the operator through the complete procedure. Subsidiary menus are reached via the keypad which enable the user to change analysis type, optimise operational modes, utilise special functions and perform statistical data analysis. The display also provides self-test diagnostics in relation to electrode status and reagent activity.
Changeover between analytes is quickly and simply effected and all fluid pathways inside the analyser can be rapidly sterilised without compromising performance.

Analytical Performance

Glucose

Lactate

Alcohol

Precision
(within run)

Plasma; n=20, CV=1.4%
@ 10.0mmol/L
Whole blood; n=40, CV=0.85%
@ 12.0mmol/L

Plasma; n=30, CV=0.6%
@ 10.0mmol/L
Whole blood; n=22, CV=1.6%
@ 5.0mmol/L

Plasma; CV=1-2%
@ 100mg/dl
Whole blood; CV=2-3%
@ 85mg/dl

Accuracy - Recovery

Plasma; mean 100.9%
(99.2-106.7%)
range 1.5-30.0mmol/L
Whole blood; mean 96.7%
(89.1-100.2%)

Plasma; mean 99.2%
(96.0-104.0%)
range 2.5-10.0mmol/L
Whole blood; mean 96.7%
(88.0-104.0%)

Spiked serum;
y (Analox) = 0.973 (true)
+ 2.1mg/dl
r = 0.9929, n = 89

Accuracy - Method
Comparison,
y = GM7

Plasma vs Hexokinase
y = 0.96 (HK) - 2.5mg/dl
r = 0.999; n = 156

Plasma vs Boehringer UV,
n = 20; r = 0.997
y = 0.967(UV) + 0.003
Whole blood vs YSI 23L,
n = 56, r = 0.998
y = 1.017(YSI) - 0.087

Whole blood vs GC,
y (Analox) = 1.04(GC)
+ 1.3mg/dl
r = 0.9905, n  = 27

Linearity

0 - 30mmol/L (540mg/dl)
using 10µl sample
0 - 50mmol/L (900mg/dl)
using 5µl sample

0 - 10mmol/L (90mg/dl)
using 7µl sample
0 - 20mmol/L (180mg/dl)
using 3.5µl sample

0 - 200mg/dl (43mmol/L)
using 5µl sample
0 - 400mg/dl (86mmol/L)
using 2.5µl sample