Generally, you can search for "Dry Ashing" or "Wet Digestion", here is my suggestion

Jones, J. B. 2001. Laboratory guide for conducting soil tests and plant analysis. Boca Raton, Fl. CRC Press.

Dear, try this-

Digest the dried tissues with HNO3 until the solution turned clear and measure heavy metal contents using atomic absorption spectrometer. 

Dear

Kindly see this paper. "Monitoring of Selected Heavy Metals Uptake

by Plants and Soils in the Area of Toruń, Poland"

Wet digestion with 6 ml H2SO4 for 0,5 g grounded sample, on a hot electric stove. You have to add 1ml or 2 ml HNO3, so that you obtain a clear solution. Bring the solution to a 100 ml volumetric flask and fill to the mark with distilled water (without filtration). The concentrations of heavy metals: atomic absobtion spectrophotometry ICP.

Good luck!

You can use this method :

Plant samples digested with a solution of HNO3/HClO4 (3:1,v/v) at 145 °C for 2 h. Metal ion concentrations were determined by using inductively coupled plasma–atomic emission spectrometry (Liu et al. 2015).

Liu Z-f, Ge H-g, Li C, Zhao Z-p, Song F-m, Hu Si-b (2015). Enhanced Phytoextraction of Heavy Metals from Contaminated Soil by Plant Co-cropping Associated with PGPR. Water Air Soil Pollut 226:29.

It may be helpful

Enhanced removal of Zn2+ or Cd2+ by the flocculating Chlorella vulgaris JSC-7

We use HNO3 and H2O2 as 'wet digestion' for organic tissues and then ICP-MS to determine heavy metals' concentrations.

thank you everyone it really helpful, but actually i wanted to utilizing or purifying (recycle) the heavy metals (ie. Cd, Cr, Pb) from hyper accumulative plats/ phytoremediation plants. i wonder how to recycle or purified this elements, and is it possible to purified the heavy metals?

im so sorry if my question is hard to undertood 

Hi,

may this could be helpful: Barbaroux et al. 2011 "A new method for obtaining nickel metal from the hyperaccumulator plant Alyssum murale"

hi rene.

thank you rene, it really help me

Regards,

You can try wet digestion method.

Wet digestion method in HNO3 in closed teflon vessels had worked fine for me when I was working with plant tissues. Of course you should adjust the time, volume of reagent and final dilution according to the LOD of your determination method. If you want to determine volatile metals too (like Hg) you should be very careful to not open the difestion vessels before they go totally cold. The determination of metals depents on the final concentration... AAS, ICPMS or ICPOES can all do the job but if your concentration level is high enough, and you are interested in metals that can be determined with AAS, go for it... it's simpler and subjected to much less interferences. ICPMS and ICPOES need an experienced analyst to give you reliable results.

As for the "recycling" question of yours... If you search in literature you will find many resins that selectively retain metals... I would advice you to search towards that direction.

Wet Digestion Method.......

Dear 

when i was working with plant tissue i used Tri-Acid digestion method i.e. HNO3, H2SO4 and HClO4 in 10:1:4 ratio

would you want to utilize the plant material that has been used in the remediation or let it rot . Are interested in the metal or the plant material for next line of experimental results. This will probably will help to decide what to do...

If the metal is not so volatile you can also use dry ashing method for pre--concentration and then acid-digestion 

To determine the amount of heavy metals (Cu, Ni, Zn, Pb, Zn, Cd) and other elements (Ca, Na, Mg, K, P) in the compost samples, a screened, fresh compost sample is dried at 105 °C and ground until reaching a grain size of 0.25 mm. Then, a compost sample weighing 1-2 g is placed in an Erlenmeyer flask and 10 mL 1:1 (volume/volume) water and nitric acid is added to perform the decomposition process. Following completion of the decomposition process, the sample is cooled; 5 mL hydrogen peroxide, 5 mL concentrated hydrochloric acid and 5 mL water is added; and the sample is re-heated. After cooling, the sample is diluted with distilled water and filtered using a 0.45 μπι membrane filter. The resulting solution is analyzed to determine the presence and concentration of various elements, (Methodenbuch zur Analyse von Kompost, 1994; AWWA, 1995). Samples are then analyzed using at the Advanced Analysis Laboratory (IAL) of Istanbul University using an ICP-MS (Inductively Coupled Plasma-Mass Spectrometer, Thermo-Elemental ICP-MS-X Series).

acid digestion.

its depend on what would like to extracted? because if it only for total metal concentration then you can try both acid based wet digestion or microwave digestion. They are varied by duration and also using different kind of chemicals. But to maintain the quality of the data, you should also use the reference plant material.

On the other hand, if you want to extract the metalloid species ( ex, arsenic) then you have to follow different techniques

Dear Eleni

Please follow the page : 

https://www.researchgate.net/profile/Parisa_Ziarati/publications

As I have done this method many times.

Best Regards

Dear Rizal,

Please see the below given link.

http://www.academicjournals.org/article/article1379770637_Jadia%20and%20Fulekar.pdf

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.466.8038&rep=rep1&type=pdf#page=57

Best Regards

Krishna

Acid digestion.

boil in HCl for 15 min and than add Nitric acid. let it cool, filter and make up the volume with water. ICP-MS is better option to quantify. otherwise, if you want to recover heavy metal from the solution, use some appropriate separation technique. selective precipitation may be use depending upon the identity of heavy metal u want to isolate.

Boil 0.5 g of powder with 6 ml concentrated H2SO4 and 2.5 ml concentrated HNO3. If the color persists, add one more ml of HNO3 and boil for total discoloration. Then transfer the solution to a 100 ml flask and fill to the mark with ultrapure water. I determined the heavy metal concentrations using a Perkin Elmer AAS 700. You also have to consider the sample (powder) moisture, determined at 105 degree Celcius, and to correct the results.

If you have the possibility, it's better to use a microwave oven for the wet digestion of samples.

Please contact me if you need more information.

Acid digestion in a microwave oven  with 6 ml HNO3 + 1 ml H2O2 using extraction method EPA 3051. 

Microwave digestion method is the best method for extracting heavy metals from plant.

Plant samples you have to rinse with deionized water and dried. 0.5 g DM plant samples have to digest using 8 mL of 69% HNO3 + 2 mL H2O2 in a microwave digestion system. The digests will be filtered and make up to 25 mL with 0.1 M HNO3.

Please also have a look at this useful ResearchGate link

https://www.researchgate.net/post/Can_anybody_suggest_a_standard_method_for_the_heavy_metal_digestion_of_plants

Wet digestion method in HNO3 in closed teflon vessels had worked fine

Dear friend, For the release of heavy metal from plant tissues, dry-ashing and wet oxidation are the two widely adopted methods.

For more details, have a look at page no. 157 to 163 of this important practical manual.

Good luck!

Wet digestion and analyze with any ICP...

acid digestion.

The person has asked this question 3 years ago and I believe already got the answer.

“The analysis of metal will be same as like as other samples, ie sediment. I also did the same thing. First of all, I separated the leaves, bark, roots, stems for each and individual plants. Then, put it freeze dryer for 72 hours and crushed it in a ceramic bowl (you can use also ceramic blander but don't use normal blander, otherwise samples can be contaminated). Then sieved it and made it powder. Then you can go through chemistry part with standard procedure which is available in your lab.”

After freeze-drying with a e.g. CHRIST GAMMA 1-20 lyophilisator, about 1 g of dried tissue is digested with 10 ml of HNO3 in a microwave-device (e.g. CEM MDS 2100). The dry weight is a small portion of the (e.g. 22–25% dependent on the composιtion of the tissue) of the fresh weight. After digestion, the sample is diluted with distilled water to 20 ml. A Varian Spectr AA 20 Plus flame Atomic Absorption Spectrophotometer can be used for the determination of Cu, Cr, Ni, Zn, Fe, Mn concentrations.

Phytoextraction method is good option.

It could be acid microwave digestion and ICP- MS for analysis.

You must use Atomic Absorption it is the most suitable chemical method for determining heavy metals in all compartments (soil, water and plant), but you must first have the plants dry at 40 ° C, grinding and chemical pretreatment.

AAS / ICP -- You can see this attachment