Dear Sir. Concerning your issue about the method suitable for digesting plant roots for AAS analysis. Digestion of plant roots can be carried out by several method such as nitric-perchloric acid wet digestion in open vessel, or microwave open vessel, or microwave closed vessel and  you can analyze less 1g weight. For more details you can see following attached protocol which may help you in your analysis.

Thanks

dear Sir..

thank you for your response towards my question. I am really appreciate it..thank you again..

Dear Syuhada,

• Simply collect the root sample and wash it thoroughly with tap water to remove any soil particle and then finally with the help distilled water.
• Dry the sample in hot air oven at 80 oC up to constant weight (for 24 hr).
• Crush the sample thoroughly with the help of mortar and pestle.
• Wight 0.5 g and take it into 150 ml Erlenmeyer flask.
• Add 5 ml of HNO3. Brown fume will appear.
• Cover it with watch glass and left it for 24 hr.
• After 24 hour heat the flask on hot plate at 100 oC for one hr.
• After cooling add 5 ml of HClO4 and cover with watch glass.
• Heat at 80 oC on hot plate, until clear content. Cool.
• Filter through whatman paper and make the final volume up to 10 or 20 ml with double distilled water.
• Go through AAS.

Kind regards.

Hi,

apart from the different methods available as mentioned by Isam, we very often face the problem of little amounts of sample - fungal hyphae, fine roots, biofilms etc. It is important to remember that you always need to compromize between sacrificing sample or sacrificing accuracy. This, of course, also depends on the elements you want to analyze. Some may be problematic because they have both low sensitivity in AAS and low background in the environment (often Pb), or you need huge amounts of sample solution (like cold vapor technique for Hg). Others may be less problematic, like Cu or Zn.

So if you cannot collect enough sample as recommended in the standard literature, you have no other option than to find your own compromize. Definitely you will need to miniaturize your digestion, and the problem of high analytical background and handling of small amounts of samples will arise.

All I can recommend you is to consult the excellent book as recommended by Isam, choose the best digestion applicable in your lab, and downsize your digestion. Take care with the quality contol, I recommend the usage of CRM, the reviewers will acknowledge correct analysis.

Best regards

dear Sir Ovaid Akhtar,

thank you for your response towards my question. so, I still need to collect at least more than 0.5mg for my dried sample as for AAS analysis..

thank you again sir. I am really appreciate your response.

hi Dr Thomas Fischer,

thank you for you response and recommendation towards my question. so, I still need to sacrifice more than 0.5mg of Balsam roots for AAS analysis afterwards. even though it seems like a little bit heart-broken to see that amount of roots that I've need to sacrifice just for one week observation, never mind. anyway, thank you again Dr.

really appreciate you response for that.

Dear Rifhan,

We generally use wet digestion method for biomass samples. Its a mixture of nitric acid and percholoric acid mixture 7:3 (v:v) and it works fine during analysis in AAS.

Incase of your small sample amount, I can recommend try to use replicates of each treatment, then even the result comes little bit error, but you will have average and standard error. And also use certified reference material (CRM) to standardize your sample analysis.

Good Luck!!

Arifin

KTH, Sweden

Dear sir Arifin,

thank you for your response. I am really appreciate it. It helps me a lot. Thank you again, sir.

Dear Rifhan,

In this scientific article, we have described the wet digestion method for biomass samples; https://www.researchgate.net/publication/282856527_Influence_of_silicon_on_arsenic_uptake_and_toxicity_in_lettuce

If anything is not clear to you, then feel free to mail me.

Best

Arifin

Article Influence of silicon on arsenic uptake and toxicity in lettuce

check this our publication

http://www.sciencedirect.com/science/article/pii/S0304389415301886

dear Adewale Taiwo,

thank you for your kind response. I am really appreciate it. thank you again.

You have not mentioned the heavy metals you want to analyze. If you use GFAAS then you can reduce your sample weight. You can take 500 mg sample and dry it in vacuum oven. Take 50 mg dry sample and digest in suprapur nitric acid and digest in micro oven in teflon container. You can inject the sample in GFAAS for analysis of Heavy metals.

@ Prof. Badal. if you use less amount of dried biomass, then you have a chance to get more error in the heavy metal concentration data in biomass. Its always good to have (+-) 1gm of dried biomass to analysis of concentration of heavy metal. Too low amount of biomass can generate wrong concentration data.

and also using  HClO4  mixed with HNO3 can also produce better digested sample.

Regards

Sandhi

dear Prof Badal,

in the research, I am using lead, arsenic and manganese as heavy metal treatment for Balsam. and my supervisor asked me to use AAS as the equipment provided in the college. so, referring to my written proposal, I need to digest first the sample before undergoing the analysis using AAS.

anyway, thank you for you kind response towards my question. I am really appreciate it. thank you again, Prof.

Here is a useful publication.

Article Ultrasonic cleaning of plant roots in their preparation for ...