Introduction
The purpose of the demonstration is to allow the students to get a "hands-on" opportunity to do a scientific experiment. The focus of the experiment should be getting as many students involved as possible, and to have fun with the experiment.

In the experiment, Blue Dextran is mixed with a dilute Phenol Red solution in a buffer containing sodium chloride and sodium acetate at pH 5.0. At this pH, the phenol red turns yellow (right in front of the students' eyes!). Upon mixing with Blue Dextran, the solution turns green. Application of the solution to a Pharmacia PD-10 column separates the green back into blue and yellow.

Materials and Methods
The following solutions will be needed:

* Blue Dextran, 3 mg/ml, in water
* Phenol Red, 10 mg/ml, in water
* 150 mM NaCl, 50 mM NaOAc, pH 5.0 (Equil. Buffer)
Note: you can purchase Blue Dextran and Phenol Red from Sigma Chemicals. Call 1-800-325-3010 for more information. Sigma product numbers are as follows: Blue Dextran/D5751 (5g/$66.80); Phenol Red/143-74-8(5g/$7.75)

The following equipment will be needed:

* Pharmacia PD-10 columns (at least 2)
Note: You can purchase PD-10 columns from Pharmacia (1-800-526-3593/ product number 17-0851-01/ Box of 30/$112.00)
* Powder funnels (1 per column)
* Ring stand with clamps
* P1000 and P20 Pipetmen/tips
* Disposable 12 x 75 mm test tubes
* Liquid waste container
* 25 ml or 50 ml plastic grad. cylinder

Experimental Procedure

1. Pre-equilibrate both PD-10 columns with at least 25 ml of equilibration buffer. This allows the second column to be used while with first column is being re-equilibrated.

2. Point out to the students beforehand that their eyes may play tricks on them. Let them think that magic is at work here. Add 1-2 ul of Phenol Red to 500 ul of equilibration buffer in a disposable 12 x 75 mm test tube. The solution turns yellow.

3. Ask the students if they know what color is made by the mixing of blue and yellow. Add 500 ul of Blue Dextran to the diluted Phenol Red solution to confirm their guess.

4. Transfer the green solution to the PD-10 column. Point out that the colors are separating from each other, but that only blue is visible at first.

5. Connect the powder funnel to the column. Add about 25 ml of equilibration buffer to the funnel and watch for the color separation. The students will notice complete separation of the blue from the yellow, with a white zone in between.

6. During chromatography, the students may have questions, and this is usually the best time to answer them, as well as to explain what is going on. A simple explanation of the theory is to compare the gel beads to "Wiffle Balls" and the difficulty or ease that big and small objects may have in fitting through the holes in the Wiffle Balls.

Labels: biochemistry, biotechnology, chromosomes, demonstration, genetic chromosomes, genetic engineering, project

Chromatography is a technique for:

separating mixtures of compounds
identifying unknown compounds
establishing the purity or concentration of compounds
monitoring product formation in the pharmaceutical and biotechnology industries



Chromatography is the science which is studies the separation of molecules based on differences in their structure and/or composition. In general, chromatography involves moving a preparation of the materials to be separated - the "test preparation" - over a stationary support. The molecules in the test preparation will have different interactions with the stationary support leading to separation of similar molecules. Test molecules which display tighter interactions with the support will tend to move more slowly through the support than those molecules with weaker interactions. In this way, different types of molecules can be separated from each other as they move over the support material.

Chromatographic separations can be carried out using a variety of supports, including immobilized silica on glass plates (thin layer chromatography), volatile gases (gas chromatography), paper (paper chromatography), and liquids which may incorporate hydrophilic, insoluble molecules (liquid chromatography).

Labels: biotechnology, chromosomes, genetic chromosomes, pharmaceutical, techniques

Imagine a diet where you can - and should - eat carbs. No guilt. No cheating. Eating by a prescribed plan that includes carbs can make you feel good and lose weight.

Serotonin is a chemical that tells your brain you are full so you stop eating. It restores good feelings and removes feelings of stress that often cause us to overeat

Serotonin is essential for weight loss as it is the one brain chemical which shuts off our appetite before our stomachs are stuffed. Serotonin is the satiety or satisfaction chemical. When your brain makes serotonin, your appetite is shut off as completely as for example your thirst is when you drink enough water.

by increasing serotonin through diet alone, we could not only reverse antidepressant weight gain but potentate substantial weight loss. This is because the increase in serotonin through diet program stopped the cravings and feelings of not being satisfied caused by the drugs.

Labels: biopsychiatry, diet, neurotransmitter, serotonin

More than 100,000 chemical reactions go on in your brain every second! The brain is also a radio transmitter, which sends out measurable electrical wave signals. In fact the brain continues to send out these signals for as long as 37 hours after death!


Scientific research over the last several decades has led to the revolutionary discovery of opiate-like chemicals in the body that associate with opiate specific receptors in the brain and spinal cord, including Serotonin, a hormone manufactured by your brain.

Low Serotonin levels are believed to be the reason for many cases of mild to moderate depression which can lead to symptoms like anxiety, apathy, fear, feelings of worthlessness, insomnia and fatigue. We are learning that depression is related to and a number of other health issues. Depression is the nation's most prevalent mental health problem, affecting about 15 million Americans who spend about $3 billion a year on drugs to battle it. Almost all of these medicines target either serotonin or norepinephrine, brain chemicals which are neurotransmitters.


Serotonin is found in gastrointestinal tract, platelets, and central nervous system. It regulates mood, appetite, sleep in your central nervous system and controls muscle contraction in your gut. Another important role of serotonin is as vasoconstrictor,realeased by enterochromaffin cells at the surface of your body, when platelets bind to a clot.

In recent years anti-depressants are among the most widely prescribed medications, in spite of their side-affects. The presumption is that a chemically induced sense of well bring is better than none. Withdrawal from these medications can be particularly hazardous and must be managed carefully. Scientists have long hunted another way to attack depression.

It has been discovered that some foods influence the brain's behavior, and the brain's neurotransmitters, which regulate our behavior, can be affected by what we eat. Research is showing that some foods such as bananas and turkey have proteins that help to create the chemical seratonin. So, diet may contribute to depression, especially poor eating habits and constant snacking on junk foods.

We really do not know the triggers for hunger or appetite. It seems that serotonin is involved, but where and how are currently unknown. Serotonin release is triggered by a carbohydrate load (sugar, etc.) and there are many who feel that eating Carbohydrates under stress is aimed at this serotonin release.

One theory about how depression develops centers on the regeneration of brain cells -- a process that some believe is mediated by serotonin, and ongoing throughout our lives. According to Princeton neuroscientist Barry Jacobs, PhD, depression may occur when there is a suppression of new brain cells and that stress is the most important precipitator of depression. He believes that common antidepressant medications, such as Celexa, Lexapro, Prozac, and Paxil -- designed to boost serotonin levels -- help kick off the production of new brain cells, which in turn allows the depression to lift.

Although it is widely believed that a serotonin deficiency plays a role in depression, there is no way to measure its levels in the living brain. Therefore, there have not been any studies proving that brain levels of this or any neurotransmitter are in short supply when depression or any mental illness develops. And while blood levels of serotonin are measurable -- and have been shown to be lower in people who suffer from depression -- what doctors still don't know for certain is whether or not the dip in serotonin causes the depression, or the depression causes serotonin levels to drop.





Here are some natural ways to help you boost serotonin up:

1. have a set sleep/wake schedule.

2. get some sun; At night your brain is instructed by your retina to make melatonin, your "off" switch. When you wake up, make sure you see some natural sunlight. The first light you see in the morning is your "on" switch. When your brain's switch turns on, serotonin is created, your serotonin levels rise, and you are motivated to function throughout the day.

3. Exercise regularly - Even gentle activities like yoga and walking keep your heart rate elevated and are known to help your brain keep its serotonin levels up. Try to exercise for 30 minutes at least 3 days per week.


4. Protein and carbs - Studies show that if you eat a tryptophan-rich protein at lunch, then switch to a carb/grain meal in the evening, you will be less likely to overeat and your serotonin levels will likely raise. Foods like turkey, beans, and cottage cheese are rich in tryptophan. Foods like amaranth and quinoa are high-protein carbohydrates that are good for you and your serotonin levels.

5. Take the time to enjoy your life! If you are schedule-oriented, add it to your agenda because your life will probably be much more productive if your serotonin levels are high enough to keep you calm and happy.

6. Have fun - Spend time with your favorite people. Listen to songs that make you feel like you are on top of the world. Laugh! Laughter raises your serotonin levels by releasing a bunch of the chemical at once. Make it a point to laugh at least 17 times today and see how you feel by bedtime.

Labels: biopsychiatry, CNS, depression, laugh, neurology, neurotransmitter, serotonin