My suggestion i to use a Blood glucose meter developed for diabetes (FreeStyle, mini (Abbott) )

We use the Trinder glucose assay kit (Sigma) and a 96 well microplate reader to quantify [glucose] in crayfish. Lee et al. (2000) have published papers with this protocol: http://www.ncbi.nlm.nih.gov/pubmed/10766968

Not for all of sugar matrix can be test, blood glucose in haemolymp is possible to measured and it could be indicated for stress and metabolism responses.

We use a RANDOX kit to measure glucose from shrimp plasma with good results!

The anthrone reaction measures all the sugars but not accurately unless there is only one sugar and you have used that sugar as the standard. It gives similar but not identical molar color responses for each sugar which are not stoichiometric and thus the standard curve is essential. Crustaceans have both glucose and trehalose as major serum sugars. An example of a workaround ... if only the two sugars are in the mixture then one can apply both an anthrone and an enzymatic glucose assay and then estimate trehalose by subtraction of glucose.

If you are planning to measure glucose (exclusively, not other sugars in plasma) I recommend you to use the Randox glucose assay kit (GL3981) which is based on the enzymatic oxidation of glucose by the enzyme glucose oxidase. The hydrogen peroxide produced, reacts with phenol and 4-aminophenazone to form a red - violet quinoneimine dye. The intensity of the final color is directly proportional to the glucose concentration and is measured at 505 nm. You can find the methodology that we used in: Sánchez-Paz, A., García-Carreño, F., Hernández-López, J., Muhlia-Almazán, A., and Yepiz-Plascencia, G. M. 2007. Effect of short-term starvation on hepatopancreas and plasma energy reserves of the Pacific white shrimp (Litopenaeus vannamei). Journal of experimental Marine Biology and Ecology, 340(2):184-193. We measure glucose with small amounts of sample in microplate

I suggest to use a glucose oxidase method which we used to measure glucose levels in the hemolymph in response to hormone treatment (Mosco, A, Zlatev, V, Guarnaccia, C, Pongor, S, Campanella, A, Zahariev, S and Giulianini, PG. 2012. Novel Protocol for the Chemical Synthesis of Crustacean Hyperglycemic Hormone Analogues — An Efficient Experimental Tool for Studying Their Functions. PLoS ONE 7:1, e30052). Choose one method, and stick to it (brand included) throughout your experiment, because glucose values can change depending on the method used.

Hi,

Colleagues have already offered several good options. So, just for you to have a few more and therefore evaluate your option money-wise (check how many samples you can perform with each kit), check the following papers for accuracy and methods.

1- Effect of dissolved oxygen level on respiratory metabolism, nutritional physiology, and immune condition of southern king crab Lithodes santolla (Molina, 1782) (Decapoda, Lithodidae). Kurt Paschke, Juan Pablo Cumillaf, Sergio Loyola, Paulina Gebauer, Mauricio Urbina, María Eugenia Chimal, Cristina Pascual, Carlos Rosas

Marine Biology. 04/2012; 157(1):7-18.

They use a God-Pad, Merck 740393 kit.

2- Should I stay or should I go?: Physiological, metabolic and biochemical consequences of voluntary emersion upon aquatic hypoxia in the scaleless fish Galaxias maculatus. Mauricio A Urbina, Chris N Glover. Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology. 05/2012.

They use a Gluco-quant, Roche diagnostic, Germany.

Just as a general advice, keep on eye in proteins as interfere in some methods. I am assuming that are also planning to measure glycogen in several tissues. the papers suggested also described methods for glycogen.

All the best!

Dear all of you

Thank you so much!!! All suggestions are very helpful for me. Now I've listed all of them for discussing with my mentor to see which one is the most appropriate for us.

Best regards!

Yes, anthrone reaction is a reliable method for carbohydrates in crustaceans. There are other methods as well - such as phenol-sulphuric acid method (Dubois et al., 1956). Anilkumar Gopinathan

After precipitating protein in the sample using TCA, the supernatant is used for the estimation of total free sugar using Anthrone method suggested by Roe et. al. I used this method for crab, prawn as well as lobster. However, if u wanted to estimate glycogen, u need to precipitate it in the supernaantt by adding 95% alcohol overnight at 4 degree C, dissolve the precipitated glycogen in distilled water and quantify using anthrone method

Yes , use the sugar test kit and correct protocol and carry on to get good results. Best wishes