1 gram of fish sample was add into 25ml nitric acid and heat until left 5ml of nitric acid and diluted with deionized water to 100ml. and i determine with ppm using AAS. lets say i determined 7.3922ppm for Calcium concentration. May I konw how to determine in ug/g? thanks for help.
Hi Eva,
ppm means parts per million. It can be expressed as mg/L or mg/1000 ml or mg/kg. For an example, if a sample has sodium 50 ppm means, 50 mg/kg or 50mg/1000 ml (if you take 1 kg or 1000 ml of sample, it has 50 mg of sodium). In your case, the concentration of calcium is 7.39 ppm. It means 7.39 mg/1000 ml. So, now you can easily convert this into micro grams/g. if your sample volume is 1000 ml, amount of calcium is 7.39 mg. But you have the sample volume 100 ml. So, you have 0.739 mg calcium. This 0.739 mg calcium came from 1 g of fish. So, the concentration of calcium in fish is 0.739 mg/1 g of fish. Since you need micro grams/g,
0.739 mg/1 g = 0.739*1000 micro grams/1 g = 739 micro grams/1 g = ~ 740 micro grams/1 g
Hope, this will help you.
You can use Atomic Absorption Spectrometer : In the method: 2.0 g sample is weighed and ashed in the furnace at 550 oC for 90
mins.The ash will be as dissolved in 5 mL of concentrated nitric acid and made up to 25 mL volume.
Dear Eva Yeo,
Please find the details for determining metals in fish and fish products, then convert to microgram per gram.
Best regards
Aly
Article Healthy cookies from cooked fish bones
Dear Eva,
If you mean ug Calcium/g of fish, based on your information the calculation is the following:
7.4 ppm Calcium = 7.4 mg Ca/1000 mL = 0.74 mg Ca/100 mL = 0.74 mg Ca/g of fish = 740 ug Ca/g of fish.
Best regards,
Roberto
Hi Eva,
ppm means parts per million. It can be expressed as mg/L or mg/1000 ml or mg/kg. For an example, if a sample has sodium 50 ppm means, 50 mg/kg or 50mg/1000 ml (if you take 1 kg or 1000 ml of sample, it has 50 mg of sodium). In your case, the concentration of calcium is 7.39 ppm. It means 7.39 mg/1000 ml. So, now you can easily convert this into micro grams/g. if your sample volume is 1000 ml, amount of calcium is 7.39 mg. But you have the sample volume 100 ml. So, you have 0.739 mg calcium. This 0.739 mg calcium came from 1 g of fish. So, the concentration of calcium in fish is 0.739 mg/1 g of fish. Since you need micro grams/g,
0.739 mg/1 g = 0.739*1000 micro grams/1 g = 739 micro grams/1 g = ~ 740 micro grams/1 g
Hope, this will help you.
The final volume of fish digest diluent, submitted to AAS, was 100 mL.
The estimated Ca levels in fish were 7.392 ppm or 7.392 mg/kg (Note: 1 ppm = 1 mg/kg).
*Remember, 1 kg (water) = 1 L (water) (Note: Density of water = 1 kg/L @ 25 C)
Therefore, Ca levels (in fish diluent of volume 100 mL) = 7.392 mg/kg = 7.392 mg/L = 7.392 mg/1000 mL = 0.7392 mg/100 mL = 739.2 ug/100 mL
Since, 1 g fish was digested and later diluted to 100 mL, therefore, it is implied that the Cal levels estimated in 100 mL diluent is equivalent to Ca levels in 1 g fish.
Ca levels (in fish) = 739.2 ug/g
Hope it helps and gives you better understanding of unit conversions.
Cheers... :)
I am agree with Md. Ekramul Karim
ppm is part per million
therefore 1 ppm = 1 mg/kg = 1 mg/1000g = 1000 ug/1000g then,
1 ppm = 1 ug/g
how do I convert the concentration from microgram/litre to nanogram/gram?
Hi Ritesh Kumar Panda,
units of volume can be converted in units of mass if you know the density;
while the conversion of micrograms in nanograms is only a matter of calculation and previous answers can help.
- Badges
- Science topic
- Similar topics
- Medicine
- Nutrition and Dietetics
- Nutritional Medicine
- Food Science