1 LABORATORY ACTIVITY NO. 1 NAME: ___________________________________ DATE: ____________ COURSE: ___________________________________ SCORE: ____________ SECTION: ___________________________________ BIOPHYSICAL TECHNIQUES @ HOME Biophysical techniques fall into two major categories: preparative and analytical. Preparative techniques are those that purify or isolate biological specimens (organisms, cells, and molecules) or otherwise get them ready for use in some other process or further experimentation. Analytical techniques are those used to measure physical aspects of a biological system. Many biophysical techniques fall into both categories at the same time. This laboratory activity is divided into two parts. The first part is a simple preparative technique in extracting the DNA from tomato and banana fruit. The second part is a simple chromatographic method to separate the constituent colors in a permanent ink marker. PART I: DNA EXTRACTION A. Objectives: At the end of the experiment, the students should be able to separate the DNA from the samples and compare the appearance to each other. B. Materials: 1 banana 1 tomato Cheesecloth or any piece of clean cloth for filtering 1 pack of dishwashing liquid 2 glasses and 1 plastic cup 10 teaspoons of table salt 2 teaspoons ½ cup water (tap, mineral, distilled) 2 zip-lock bags Cold 70% Isopropyl alcohol 2 toothpicks C. Procedure: 1. Prepare the lysis buffer a. In ½ plastic cup of tap or distilled water, dissolve a teaspoonful of table salt. Continuously stir to totally dissolve the table salt. Add 10 teaspoons of JOY dishwashing liquid then carefully stir the solution without creating bubbles. Set it for a while. 2. Place one tomato and one banana in separate zip-lock bags, press the air out then seal. Softly mash the tomato/banana with your fingers until it becomes a juice puree (1-2 minutes). 3. Add 15 teaspoons of lysis buffer you created to the tomato and 20 teaspoons to the banana and then press the air out of the bag and seal. 4. Mash the tomato/banana carefully for 1 minute without creating many bubbles. 5. Using a cheesecloth, filter the mashed banana/tomato with the lysis buffer. Place the filtrate in small glass. 6. Tilt the glass and pour in an equal amount of cold 70% Isopropyl alcohol, ¼ of glass, through the funnel and down the sides of the shot glass. This will allow for better separation of the DNA. 2 LABORATORY ACTIVITY NO. 1 7. Place the glass so that it is eye level. Using the toothpicks, collect DNA at the boundary of alcohol and strawberry juice. Do not stir the strawberry/banana juice; only stir in the above alcohol layer. D. Data 1. Draw the DNA you see in each of your glass below. 2. Why do we need to crush the tomato and banana? 3. What role did the dishwashing liquid, table salt and 70% isopropyl alcohol play in the DNA extraction? 4. What parts of cells were most affected by the soap? 5. What is DNA used for when it is extracted? E. Conclusion: (Write down your conclusion below) 3 LABORATORY ACTIVITY NO. 1 PART II: Chromatography Experiment with Permanent Markers Chromatography serves mainly as a tool for the examination and separation of mixtures of chemical substances. It has two components namely the stationary phase which is always composed of a “solid” phase or “a layer of a liquid adsorbed on the surface a solid support” and mobile phase which is always composed of “liquid” or a “gaseous component.” A. Objective: At the end of this experiment, the student should be able to observe how chromatography can be used to separate mixtures of chemical substances. B. Materials: Paper towel / Tissue strips Glass cups Permanent markers (the colors black and green were most interesting) Rubbing alcohol, nail polish remover, and vinegar C. Procedure: 1. 2. 3. 4. Cut paper towel / tissue in strips. Draw a heavy line across the strip with a marker (or a couple of thin lines). Fill cups with a bit of the solvent you are testing out: vinegar, nail polish remover, or alcohol. Hang the paper strip over the edge of the glass so that the paper towel touches the liquid, but the line is above the liquid. D. Data: 1. Take photos of your experiment and paste the photos below. 4 LABORATORY ACTIVITY NO. 1 2. How many colors separated from the black ink? 3. Among the three solvent that you used, which is more effective in separating colors in blank ink? 4. Why did the inks separate? 5. In the experiment you did, which is the mobile phase and which is the stationary phase? 6. From your results, what can you conclude is true about black ink? E. Conclusion (Write down your conclusion below) REFERENCES: Activities: Classroom Activities in Plant Biotechnology. (nd). Retrieved on 2nd of June, 2020 from https://www.apsnet.org/edcenter/disimpactmngmnt/labexercises/PlantBiotechnology/Pages/Activity1.aspx Coskun O. (2016). Separation techniques: Chromatography. Northern clinics of Istanbul, 3(2), 156–160. https://doi.org/10.14744/nci.2016.32757 Friedman, J. (2017) Paper chromatography. Retrieved on 2nd of June, 2020 from https://www.biologyjunction.com/paper_chromatography_report.htm#:~:text=The%20purpose%20of%20t his%20experiment,of%20mixtures%20of%20chemical%20substances.
