Sports Drinks and Nanotechnology
STUDENT LAB GUIDE
SPORTS DRINKS AND NANOTECHNOLOGY
INTRODUCTION AND INSTRUCTIONS
WHAT IS NANOTECHNOLOGYAND THE NANOSCALE?
Nanoscale technology involves using particles ranging from 1nm to 100nm (one nanometer is equal to one billionth of a meter). Nanoparticles are so small that they cannot be seen with the naked eye or even a light microscope. One very unique feature of nanoparticles is that at the nanoscale their physical and chemical properties are very different compared to larger samples of the same substance. This is called the oligodynamic effect. For example: some may change colors and become chemical indicators, some may become insulators, some may have different melting points and some can act as semiconductors.
Nanoscale properties have enabled many organisms to evolve special nanoscale mechanisms that have been part of the natural world for a long time. Two examples are the glue that mussels secrete which bind them to rocks in the water and the tiny hairs on the feet of geckos which allow them to climb on slick glassy surfaces.
WHAT IS NANOGOLD AND HOW DOES IT WORK?
One important nanoparticle, nanogold, has been around since the Middle Ages. Artists have used nanogold to create the various colors in stained glass. By adding different sizes of nanogold particles to the glass they were able to create all the different colors visible in a stained glass window. For example: the red glass contains particles around 20nm across, 30nm particles produce pink glass, and 80nm particles produce orange glass. These artists, however, had no way to measure the size of the particles or to know the scientific explanation behind the variation of the colors.
Nanogold color depends on the size and shape of the nanoparticles and the distance between them. The color may appear as either red or orange or blue.
The phenomenon called surface plasmon resonance(SPR) accounts for these variations. Light shining on the surface of a metal produces surface plasmon, a condition in which a group of electrons move back and forth together across the metal surface. The electrons ripple back and forth not unlike waves of water moving across a pond. Resonance occurs in the plasmon when the electrons are moving at the same frequency as the light. In resonance the electrons absorb and scatter light, thus producing various colors.
Nanogold particles resonate at frequencies within the visible spectrum. The smaller particles absorb and resonate at the range of the spectrum where the purple, blue, green and yellow wave lengths of light are located and therefore appear red. The larger nanogold particles absorb and resonate at the range of the spectrum where green, yellow and red wave lengths are found so these particles appear blue.
The Nanogold/Electrolyte Lab utilizes this technology. The nanogold particles serve as a biosensor, which works in the following way:
1. The negative charge on the surface of the nanogold particles repels other neighboring nanogold particles, thus keeping the particles small.
2. When an electrolyte (salt) is dissolved in water, cations (ions with a positive charge) and anions (ions with a negative charge) are formed.
3. The positive cations from the electrolytes freely bind to the negative surface of the nanogold particles, creating a neutral cation-nanogold particle.
4. As more and more cations bind to the nanogold particles’ surfaces, they begin to accumulate and form clusters.
5. The clusters are much larger than the original nanogold particles.
6. The increase in size causes a color change in the solution.
7. The net size of the nanogold particles have increased from the formation of clusters and the surface plasmon resonance has changed, thus changing the wave length of absorption.
8. The end result is a different color that is consistent with the size-color effect.
WHY DO WE NEED ELECTROLYTES?
When you exercise, you sweat. When you sweat, you lose water and electrolytes (salts). All muscle cells use sodium to close or contract the cells and potassium to relax the cells or stop the contraction. Calcium starts the closing process with sodium managing the actual closing. Magnesium starts the relaxing process with potassium managing the relaxing process within the cell. In order for the human body to function properly under physical stress, all four of the mineral electrolytes (sodium, potassium, magnesium and calcium) are absolutely required. If they are not replaced, you could have a cramp or arrhythmia (irregular heart beat). Prolonged effects of improper replenishment can result in serious injury such as a heart attack or circulatory shut-down and even death.
To help replenish the electrolytes lost in sweating, sports drinks may be consumed. Nanotechnology can be used to test various sports drinks to determine which have the most electrolytes. By this method, you can determine which of these sports drinks might be the best choice to consume after exercise.
RE-READ THE INTRODUCTION
Materials:
Plastic cups
Vial containing pre-made gold nanoparticle solution
Microcentrifuge test tubes
Microcentrifuge test tube holder
Plastic pipets
Black Sharpie
Piece of white paper
Various electrolytes
Distilled water
Bucket for liquid waste
Student Lab Guide----Sports Drinks and Nanotechnology
Handout A, Handout B
Table 1: Data Collection
PROCEDURE:
1. Complete Handout A and read through ALL the steps before you begin the Lab.
2. Label 7 microcentrifuge test tubesusing the black Sharpie with the letters A, B, C, D, E, F, G. Label 7 plastic pipets using the same letters.
3. Place each microcentrifuge test tube in the test tube holder.
4. Label 1 additional plastic pipet nanogold colloid. Label an additional microcentrifuge test tube CONTROL and add 1.5ml (approximately 30 drops) of the nanogold colloid using the nanogold pipet.
5. Use the nanogold colloid pipet to load one ml (approximately 20 drops) of the nanogold colloid to each of the labeled A through G test tube
6. Add the sports drink test samples to the test tubes as follows: Use the pipet labeled “A” to add 0.5ml (approximately 10 drops) of the sports drink in the plastic cup labeled “A” to the test tube labeled “A”. Repeat the process using pipet “B”, sports drink“B” and test tube “B”;follow the same process for C, D, E, F, G.
7. Read the instructions under Table 1, observe the sample colors approximately 10 minutes after the nanogold colloid has been added to the samples, and enter your findings in Table 1: Data Collection.
Prepared by: Dr. Debbie Payne, Ruth H. Liddell, Shirley K. Scarbrough
Alabama State University, Math, Science Partnership, Spring 2013
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