Is the amount of iron printed on pharmaceutical iron supplements labels accurate? PDF

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Summary

An IB Internal Assessment Standard Level on chemistry lab report (Chemistry SL IA)...

Description

Chemistry Internal Assessment Iron (II) concentration in iron supplements Session: May 2018

https://www.livestrong.com/article/316855-iron-supplements-for-thalassemia-minor/

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Content Page

Introduction ....................................................................................................................................3 Hypothesis .......................................................................................................................................4 Variables .........................................................................................................................................4 Materials .........................................................................................................................................4 Methods ...........................................................................................................................................4 Lab safety and precautions ...........................................................................................................6 Raw and processed data ................................................................................................................6 Evaluation .......................................................................................................................................7 Limitations, Improvements, errors ..............................................................................................7 Conclusion ......................................................................................................................................8 Bibliography ...................................................................................................................................8

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Introduction Iron(𝐹𝑒) is a vital element for human being’s health and an essential mineral that forms hemoglobin, an oxygen carrying protein. Therefore, iron is an important element used in blood production. Hemoglobin makes about 70% of our body’s iron and it is found inside red blood cells. Red blood cells help us to exhale by removing carbon dioxide(𝐶𝑂2 ) from our body and transporting it to our lungs. However, if our body does not contain enough iron, it will lack adequate healthy red blood cells. The lack of adequate healthy red blood cells is called iron deficiency anemia. Figure 1: Amount of RBC and WBC in a normal body vs in a person who suffers from Iron Deficiency Anemia body

A common way to treat iron deficiency anemia is by taking iron supplements, which come in different types; including pills, capsules, drops, and extended-release tablets. Iron supplements help increase the level of iron and hemoglobin in our body. Iron supplements have supplements facts behind their package, which give us information about the concentration of iron per tablet and it usually stated in milligrams. As a person who is diagnosed with iron deficiency anemia, my doctor suggests me pills that are best for me according to the amount of elemental iron the pills contain. I have been very curious to know whether the labels on iron supplements have the stated amount or not. To get answers, redox titration was used with 1 tablet (𝑥) and it was compared with the amount stated on it’s package.

Research question Is the amount of iron printed on pharmaceutical iron supplements labels accurate?

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Hypothesis I have a strong belief that the amount printed on iron supplements labels are accurate because the Food and Drug Administration (FDA) has issued regulations to make sure that the labels are done correctly.

Variables Independent

Variable iron supplements

Dependent

Iron(II) concentration in iron supplements

Control

Amount of trials

Justification An iron supplement that I use myself, and one of the famous tablets ever has been chosen The amount of iron (II) in different tablets is highly dependent on the brand of the tablets 3 trials were done for better and more accurate result

Unit mg

g/mol

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Materials • • • • • • • • • • • •

Iron tablets (45 𝑚𝑔 𝑏𝑜𝑡𝑡𝑙𝑒, 5 𝑠𝑎𝑚𝑝𝑙𝑒𝑠) Digital scale (1𝑥) pestle and mortar (1𝑥) Sulfuric acid 250 ml volumetric flask (1𝑥) 100 ml beaker (1𝑥) Pipette (1𝑥) 250 ml conical flask (1𝑥) Burette (1𝑥) Potassium manganate (VII) Funnel (1𝑥) Wash bottle (1𝑥)

Method To fully estimate the amount of iron (II) in an iron tablet, 5 tablets were dissolved in dilute sulfuric acid and redox titration was used against the reaction below, which is a potassium manganate(VII) solution.

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1 iron tablet bottle with the iron content of 45 mg was taken. (Tablet bottle x) •

Preparing the iron tablets 1. 5 tablets were taken from the bottle 2. The mass of the tablets was taken 3. The tablets were then crushed into small pieces with mortar and pestle 4. The crushed pieces were transformed into a beaker 5. 100 𝑐𝑚3 of dilute sulfuric acid was poured into the beaker 6. The solution was transformed into a 250 ml volumetric flask 7. Sulfuric acid was used to fill the volumetric flask, so it could make up to the mark 8. The volumetric flask was stoppered and revered a couple of times 9. The solution was labeled with “Iron (II) ions”

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Titration 1. Deionized water was used to wash the pipette, conical flask and the burette 2. Potassium manganate (VII) was used to rinse the burette 3. Iron (II) solution was used to rinse the pipette 4. Iron (II) solution was used to fill the pipette with the help of the pipette filler 5. The solution along with the pipette were transformed into the conical flask

10 𝑐𝑚3 of dilute sulfuric acid was added to the solution to acidify the solution funnel was used to fill burette with potassium manganate (VII) solution Readings and observation were taken from the top of the meniscus The conical flask was placed on the white tile as the solution from the burette was poured into the flask 10. The conical flask was swirled continuously and the walls of the conical flash were occasionally washed with deionized water, using a wash bottle 11. The end-point of the titration was detected when ‘the first persisting pink color’ was seen 12. The burette reading was written and recorded 6. 7. 8. 9.

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Calculation 1. The procedure was repeated two other times, adding the potassium manganate(VII) dropwise approaching the endpoint 2. The trials were summed 3. The concentration of iron (II) was calculated 4. The mass of iron in an iron tablet was calculated

Lab safety and precautions Safety goggles, lab apron and gloves were wore throughout the entire experiment to prevent any incident. As for obvious reasons, I could not mention the brand of the tablet that were used throughout this investigation.

Raw and processed data ∫ 𝐶𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑝𝑜𝑡𝑎𝑠𝑠𝑖𝑢𝑚 𝑚𝑎𝑛𝑔𝑎𝑛𝑎𝑡𝑒 (𝑉𝐼𝐼)𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛 = 0.005 𝑀 ∫ 𝑉𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑖𝑟𝑜𝑛 (𝐼𝐼)𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛 𝑢𝑠𝑒𝑑 𝑖𝑛 𝑒𝑎𝑐ℎ 𝑡𝑖𝑡𝑟𝑎𝑡𝑖𝑜𝑛 = 25.0 𝑐𝑚3 Table 1: Iron tablet bottle X (According to the label, the iron concentration is 45 mg) Mass of iron tablets 1.80 g

Trials 1 2 3

Average titre 𝒄𝒎𝟑

Initial /𝒄𝒎𝟑 ± 0.05 0.00 0.00 0.00

Final / 𝒄𝒎𝟑 ± 0.05 17 16.7 16.7

Titre / 𝒄𝒎𝟑 ± 0.1 17 16.7 16.7

16.7

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𝑉𝐴 𝑥𝐶𝐴 𝑥𝑛𝐵

= 𝑉𝐵 = 𝑀𝐵 𝑥𝑛𝐴

25𝑋𝐶𝐴 𝑥1 𝐶𝐴 =

Volume of 𝑭𝒆𝟐+ solution in total Moles of iron in this volume

16.7𝑥0.005𝑥5 25𝑥1

= 16.7𝑥0.005𝑥5

→ 𝐶𝐴 = 0.0167 𝑀

250𝒄𝒎𝟑 0.0167 0.004175 0.004175 x 54 g Mass of iron in this volume =0.22545 g 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑖𝑟𝑜𝑛 𝑥 100 𝑃𝑒𝑟𝑐𝑒𝑛𝑡𝑎𝑔𝑒 𝑜𝑓 𝑖𝑟𝑜𝑛 𝑖𝑛 𝑡ℎ𝑒 𝑡𝑎𝑏𝑙𝑒𝑡𝑠 = 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑡𝑎𝑏𝑙𝑒𝑡𝑠 =

0.22545 𝑥 100 1.80

→= 12.525%

𝑀𝑎𝑠𝑠 𝑜𝑓 𝑖𝑟𝑜𝑛 𝑖𝑛 𝑒𝑎𝑐ℎ 𝑡𝑎𝑏𝑙𝑒𝑡 = → = 45.09 𝑚𝑔

0.22545 𝑔 5

Evaluation The resulting somehow supported the hypothesis and somehow it did not. The result obtained is very close to the real data but unfortunately it is not the same. As the data suggests, the amount of iron in iron supplements is not equal to the amount mentioned. In this experiment, it was higher than the amount mentioned but I am very sure that if I got higher, some pills would give a lower concertation than mentioned. The obtained value is very close, almost similar. It should also be kept in mind that, my project is most likely to be faulty and some kind of error has happened. For that reason, I’m left with the conclusion that the amount of iron in iron supplements is very close to the real amount. Errors, limitations, and improvements A big improvement would have been that if I used more than one brand of iron supplement, and even a bigger improvement would be that I could have used different iron supplements with different mg’s mentioned. A limitation that I faced during this investigation was that I could not use deionized water to dissolve the iron tablets, instead I had to use dilute sulfuric acid. The reason is that if I used deionized water, 𝐹𝑒 2+ would immediately get oxidized to 𝐹𝑒 3+. 7

Another limitation was that I had to take the burette reading from the top of the meniscus because Manganate (VII) solution is very dark in color and it makes the meniscus difficult to see. An error would be that I did not do a rough titration and I did not write down the results so that might be an explanation as to why my final result isn’t accurate.

Conclusion As the number of people with iron deficiency anemia is increasing, so is the different brand and types of iron supplements. One type of iron supplement that was said to have an iron content of 45 mg was put into test in this experiment. The obtained result that I got was nearly a 45.09, which is really close to the actual data, but considering that my investigation is most likely to be faulty and considering my errors and limitations, I think it’s safe to say that iron supplements do contain the amount of iron they say they do. The amount might probably be a little different but it’s barely noticeable and it won’t change its effect or anything. In other words, it won’t do any good, but it won’t hurt you either. Even though there were few limitations and errors and of course, improvements required, the final result was very close to the actual data. Therefore, yes, the amount printed on pharmaceutical iron supplements labels is accurate enough. Bibliography Images; Figure 1: http://www.medicoaid.com/qod-298-iron-deficiency-anemia/ Figure 2: http://slideplayer.com/slide/10364810/ Figure 3: https://socratic.org/questions/552b4d09581e2a667e2bfe91

C. A. Lucchesi, C. F. Hirn. (1960, August 10). Titration of Total Iron in Iron(II) and Iron(III) Mixtures. Retrieved from Analytical chemistry: https://pubs.acs.org/doi/abs/10.1021/ac60165a044 Calculations and titrations. (n.d.). Retrieved from BBC: http://www.bbc.co.uk/schools/gcsebitesize/science/add_ocr_pre_2011/chemical_synthesi s/calculationsrev3.shtml Staff, M. C. (2016, November 11). Iron deficiency anemia. Retrieved from Mayo clinic: https://www.mayoclinic.org/diseases-conditions/iron-deficiency-anemia/symptomscauses/syc-20355034 The Cleveland Clinic Foundation. (2009, September 9). Oral Iron Supplementation. Retrieved from cleveland clinic: https://my.clevelandclinic.org/health/articles/14568-oral-ironsupplementation 8

Willson, D. R. (2016, August 2016). 10 Reasons Why You Might Need Iron Supplements. Retrieved from Health line: https://www.healthline.com/health/10-reasons-ironsupplements

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