GM-100: Portable Glucose Meter for Bioprocessing

The GM-100 is a hand-held, economical glucose meter designed for measuring glucose content in either cell or microbial culture media (final application to be specified before purchase). It is simple to use, quick reading, and requires a very small sample size. This device has been validated and adopted for use in several cGMP facilities.

The principle technology behind the GM-100 Glucose Meter is a merging of glucose biosensor science with microprocessor-based instrumentation. The associated single-use test strip requires a sample volume of less than 2.5 uL and has a response time of 10 seconds. The meter has a large, easy-to-read display, and can store up to 70 test results with corresponding times and dates. With its disposable test strips and compact size the GM-100 Glucose Meter is ideal for use in a biosafety cabinet, eliminating risk of contamination from biohazardous samples.

In general the best measurement range is 50-250 mg/dl.  We therefore suggest you to dilute any sample with PBS or the sugar free medium to within the desirable range for the best result.

The GM-100 can also be customized to fit your process, be it cell or microbial culture. This is critical because most glucose measurement systems utilize a similar enzymatic reaction whose reaction rate is affected by temperature, pH, ionic strength, and other components in the sample which may interfere with said enzymatic reaction. It is therefore, in reality, difficult to make one system to fit all applications. Our GM-100 is available with three most popular calibration code keys for general use with microbial and cell culture uses. In order to provide users with an even more accurate meter however, we offer free of charge a custom-made code key to fit your specific application once we are provided with few simple data from the meter and your specific process (please inquire for more details). This equates to the most ideal and economical solution for measuring glucose in bioprocessing applications.

HOW TO USE THE GM-100 GLUCOSE METER

1) Preparation of sample: take a sample and dilute it with PBS (phosphate buffer) as needed in an Eppendorf tube to the estimated glucose concentration below 300 mg/dl based on the initial known glucose concentration of your culture process. For instance, the standard glucose concentration of DMEM is 500 mg/ml. If you use this common medium for your process, all your subsequent samples should be diluted by 2 until the reading becomes <50. The optimal reading of this meter is 50-250.

Depending on the available amount of the sample, you can leave the small sample in the Eppendorf tube or take a couple drops of sample on a plate.

2) Preparation of meter: To check initially if the battery and meter are in order, plug the white check key to see if it shows ABC. Only do this later when the meter is not functioning properly such as a weak battery. Then take a pink key provided (best suitable for your culture medium as instructed. See our site for more detailed information about this) to plug in. The key number will show on the meter. For instance, use key 349 for DMEM. The meter will read 349. If you will use this same medium in your future samples, you do not need to plug this key again until the medium is changed.

3) Measurement: Then open the strip bottle and take out the number of strips you need. Plug the strip with the metal electrode end into the slot firmly until the meter reading of the lot number of the specific strip appears. If not, pull out the strip and try again. Now it is ready to dip the other end of the strip into the sample for measurement as described in 1). Stay in the sample until hearing the beep sound and then remove the tip of the strip away from the sample after counting 1 and 2 (for consistent purpose). Then wait 10 seconds for the meter reading the result. Record the reading and discard the spent strip. If a minute sample (<5 uL) is taken with a micropipette, you can feed the sample directly on the tip of the strip and wait for the beep sound as above.

Features

• Suitable for both serum and serum-free cell culture medium, and complex microbial culture medium.

• Portable, calibration-free, ready-to-use

• Direct measurement without needing to separate cells from culture medium

• User-programmable units of measurement for mg/dL or mmol/L

• Zero risk of contamination of bio-hazardous samples to device or to the environment    

Specifications

• Dimensions: 96mm x 60mm x 18.5mm

• Power Source: two AAA batteries

• Battery Life: approximately 1000 tests

• Display: large LCD

• Automation: auto-electrode insert detection, auto-sample loading detection, auto-reaction time countdown, auto-turn off

• Memory: stores up to 70 test results

• Environment: 10-40 degree C

• Required Sample Size: 2.5 uL

• Best Measurement Range: 50-300 mg/dL  

• Testing time: 10 secs.

Data

Ordering Information

For customers with an existing Thermo Fisher Science account or agreement, you may also purchase the GM-100 meter and its associated GMTS-50 test strips from the Thermo Fisher Scientific online catalog via the below links:

• GM-100 (Fisher Scientific Catalog No. NC0919378)

• GMTS-50 (Fisher Scientific Catalog No. NC0919404)