Introduction ((((Fluoride in Tea sample)) - Essay Example

Fluoride in tea sample Fluoride in tea sample Direct potentiometry utilizes ion selective electrodes (ISEs).These electrodes are special ion sensitive membranes made of glass, crystalline inorganic material or organic ion changer. The membranes are highly selective and interact only with specific ions thus allowing the ion of interest to control the electric potential. A reference electrode is used in conjunction with the ion selective electrode to measure the potential using an electrometer or pH meter.

The Nernst equation relates electrode potential to the logarithmic concentration of the measured ion. The Nernst equation is valid for very dilute solutions or solutions with constant ionic strength. Fluoride ion selective electrode responds to free ionized fluoride in solutions. This experiment aims to demonstrate the use of fluoride ion selective electrode (FISE) in the determination of fluoride concentration (TSU, 2013).Tea (Carmelia sinensins) is naturally rich in fluoride. Plants absorb nutrients (inclusive of fluoride) from the soil).

Most of these nutrients are stored in the leaves which for the case of tea are harvested for tea preparation due to easy harvesting, handling and brewing. New tea preparation techniques and consumption are deemed to have implications on the fluoride concentration. Josipa et al., (2012) determined fluoride concentration in various infusions of tea using fluoride ion selective electrodes which is a simple and fast method. In the study it was observed that the size of tea pieces greatly influences levels of fluoride in tea infusion.

The finer the tea material, the grater the extraction of fluoride. Brewing time was found to also affect the concentration of fluoride in tea infusions. Brewing times of between 10 to 20 minutes gave optimal concentrations of fluoride especially for mint and pomegranate tea. It was advised that one should drink tea prepared more than 24 hours prior to preparation. Strong correlation were observed between concentration with change of time and also packaging effect especially for green tea.References Josipa Giljanović, Ante Prkić, Marija Bralić, Mia Brkljača (2012).

Determination of Fluoride Content in Tea Infusion by Using Fluoride Ion-Selective Electrode. Int. J. Electrochem. Sci., 7 2918 – 2927Truman State University (2013). Determination of Fluoride Ion Using an Ion Selective Electrode. Truman State University CHEM 222 Lab Manual Revised 10/29/13