The Chemistry of Spray Paint Art

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Spray paint is a medium that I was introduced to by another artist and let me tell you, this is a really fun way to paint. The way that the image is formed is much different than other types of paint. You can use a clear coat to moisten your work while you are painting. Understanding negative space, lines, and shapes will help your technique. It dries very quickly, so you need to work fast. If you don’t like the way something turns out it is easy to paint over or scrape off while it is still wet. The paint will come out similar to an airbrush which makes this media perfect for stencil work. If you are just starting out don’t get frustrated. The more you work with this media, the better you will get with controlling the spray and knowing what result will come from various techniques. Experimenting with different tools and types of spray paint will add to your creation.

Spray paint is an aerosol which means you will breathe it in if you do not protect yourself. Always wear a face mask and gloves because it will get messy. Besides, the mask makes you look like a rock star and you will want gloves on to flick paint splatter on your painting. This media is best used outside not just for ventilation, but also because it will get everywhere. Keep in mind that the paint will dry faster if it is hot out. It is easy to make a lot of paintings very quickly which makes spray paint art really fun. Depending on the surface you are painting, you may need to start with primer. I like to use glossy poster board because it is inexpensive and ready to use. Understanding your tools is the key to creating the images that you want. In addition to stencils you can use cans, magazine pages, plates, putty knives, and even brushes depending on what you are trying to do.

The spray paint contains a propellant in addition to the paint. The propellant is a gas that is under so much pressure that it becomes a liquid through a process called condensation. That liquid mixes with the paint and when you press the nozzle the pressure is releases through the nozzle creating the paint mist that comes out of the can. The liquid propellant wants to be a gas at normal atmospheric pressure, so be careful because the contents are under high amounts of pressure to liquify the propellant. The ball bearing inside the can mixes the paint with the liquid propellant which is what you want. Shake well while you are working with the spray paint to get the best proportions of paint to propellant. 013

There are different types of spray paint available depending on the type of surface you are painting. General purpose and craft paint can be purchased at any hardware store. You will want to pay attention to the type of spray paint that you can get. Acrylic, latex, tempera, enamel, and oil will act very differently. Oil and water do not mix so if you decide to use paints with differing oil contents you will want to layer the higher oil content on top of paints with a lower oil content. The gloss makes a huge difference as well. If you are going to layer gloss paints start with the lowest gloss (matte) under higher gloss layers. Happy painting.

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The Art of Immunohistochemistry

Immunohistochemistry is a method that is used to detect antigens in tissue sections and cells using antibodies. It is a reaction that is based on antigens and antibodies of a tissue. There are two ways that I use IHC for drug development. The first is IHC detection of a common CD marker to identify a particular cell type in a tissue. The second use of IHC is for what is referred to as tissue cross reactivity. In tissue cross reactivity, the antibody (i.e. drug) is put on naive tissue and then detected so that we can see where the antibody is binding under a microscope. We want the antibody to bind to its target without binding to anything else. By identifying the target and engineering the antibody to target it, we are able to develop medications that will serve a specific purpose based on the epitope of the protein that it is meant to bind to.

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The tissue is sectioned on a cryostat or microtome and can be fresh frozen or paraffin embedded. There are different methodsĀ  that are needed for paraffin tissues compared to fresh frozen tissues. For successful IHC staining of paraffin embedded tissues, an antigen retrieval step is needed in the assay. Some common ways we perform antigen retrieval include heat induced retrieval, and the application of proteolytic enzyme solutions such as Trypsin or Proteinase K. Fixation is important to preserve the morphology and target proteins in the tissue. Paraformaldehyde is a common fixative, however, acetone, methanol, and a combination of acetone and paraforamlehyde are also used. It is crucial to test multiple fixations to select the most appropriate condition for the tissue and the target proteins.

We need to quench endogenous peroxidase activity because the enzymes peroxidase and alkaline phosphatase are often used in IHC to convert the colorless chromagens into colored end products for detection of antibody binding. The idea is to detect the antibody binding with minimal background staining. Common causes of increased background could indicate that the concentration of the antibody is too high so it is important to test multiple concentrations to select the optimal concentration to use for the assay. Endogenous avidin binding activity can also lead to increased background staining which can be blocked by treating the tissue with biotin. Sometimes polymer-based detection methods can also cause background staining which can be decreased by increasing the quantity and time period for wash steps between reagent treatments.

Depending on the primary antibody (i.e. the drug or CD marker), a secondary and possibly a tertiary antibody is needed. Think of it as building a ladder to amplify the signal of where the antibody is binding while blocking all of the background noise so that we can see what is happening. There are many reagents available to develop the method for an IHC assay, so there are multiple methods, reagents, concentrations, and incubation times that can render the same result. We find the best method for detection of the antibody within the assay and then identify target and non-target binding of the antibody to determine the safety and effectiveness of the drug.iPhone June2015 195

A pathologist is able to analyze the slides to identify any binding of the antibody to the tissues. The staining on the tissues can be quite remarkable. Seeing the results of an IHC stain is like looking at a painting once it is complete. Instead of brushes and paint we are using reagents and antibodies. The tools we use in the laboratory work together to create a window into what is happening inside of our bodies. As simple as it sounds to cure disease or make medicine, it is much more complex just as our bodies are indefinitely complex. By building on the knowledge of those before us and continuing research we will advance medical technology and have the capability to save more lives than we ever thought possible.

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The Art of Pyrotechnics

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I have always been fascinated with fire, but fireworks take the cake. If you are close enough you can hear the sound of it whistling through the air before the big BOOM that fills the sky with radiant colors. That boom is what really gets my heart pumping. The colorful, sparkling display of light is not only awe inspiring, but represents a feeling of celebration and wonderland. I can’t help but to think about how exciting it must be to design a fireworks show. The timing, the colors, the shapes we can make are all part of the art that is…blowing stuff up.

There are many different types of fireworks including sparklers, skyrockets, and flying spinners. The color is created by heating the metal salts. Red is caused by strontium and lithium salts, orange by calcium salts, yellow by sodium salts, green by barium and chlorine, blue by copper and chlorine, purple by mixing the red and blue strontium and copper compounds, and silver by aluminum, titanium, or magnesium. The reaction can be explained by the basic chemistry of oxidation and reduction reactions. The appearance is determined by how the components are arranged in the shell. Timing the ignition is done with different types of fuses or with a control panel designed to ignite them from a distance.

Fireworks are not the only pyrotechnics that we get to enjoy. They are also special effects that are used in film to simulate explosions, smoke, and flames. Flames can also be used for a dramatic effect on stage during a concert. Performance can be illuminated for fire dancers with choreographed routines to music. Fire eating or fire breathing is not just for the circus, but also used in flair bar tending. Just as the color of fireworks is determined by the metal salts that are heated, the color and amount of heat produced by fire is determined by what chemical is ignited.

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Before you decide to start lighting things on fire, remember that you are setting off dangerous chemical reactions as beautiful as they can be. Fire needs three things to survive: oxygen, fuel, and heat. All of the ingredients are present and available to cause a potential for disaster. Pyrotechnicians are responsible for the safe storage, handling, and functioning of their devices just as you should be with home fireworks. That being said, try not to burn the neighborhood down or blow yourself up. The ability to control the chemical reactions is what makes pyrotechnics both an art and a science.

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The Chemistry of Oil Painting

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I will admit that oil paints are not my primary go-to medium, but for many artists it is preferred. I like to work with acrylic paint because it is water soluble and generally don’t need to worry about paint fumes. There are many reasons, however, to choose oil paint as a media. Oil paints dry very slowly which allows the artist to manipulate the paint longer and remove areas of paint that they do not like. My interest is particularly peaked because of the ability to work on reflective images without snagging your brush in partially dried paint. I prefer to paint using layers which is why I have gravitated toward the faster drying time of acrylic, but oil paints can be layered as well. This method of layering is called indirect painting whereas direct painting is used to create images in a single application.

The chemicals used in oil paints and with the paint can be toxic, so it is important to understand what you are working with. Certain pigments and metals in the paint are more dangerous than others such as cadmium, lead, copper, and cobalt. There are many other toxic pigments that can be found in paint, but when used properly and safely there is nothing to worry about. Just like we would in a laboratory, it is important to use the appropriate protective gear for the chemicals we are using. Anyone that has had experience with painting knows that it takes a lot of time sitting in front of your piece before it is complete, so ventilation is a must. Wash your hands and don’t eat or drink when you are painting to avoid ingestion. If you plan to use powdered pigments, wear a face mask to avoid inhalation.

Other chemicals to be aware of are of the diluent and solvent arena. Turpentine is used as a paint thinner and also in the production of varnishes. In addition to the flammable and corrosive traits of turpentine, it is a carcinogen. Lucky for us, there are alternatives to using turpentine that I would highly recommend. Citrus thinner is made from citrus oil. It smells better and is not harmful like turpentine. Still, it is important to use it in a ventilated area. In addition, linseed oil and walnut oil can be used to thin oil paints. Now we get to my main concern with oil paints: drying time. Alkyd mediums such as Liquin by Winsor & Newton or Gamsol by Gamblin will speed up the time it takes for the oil paint to dry. Gamblin also makes alkyd oil paint that dries faster than traditional oil paints without the extra step.

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When used properly there is nothing to fear about using oil paints. Mixing the wrong things can lead to health issues, so understanding the chemicals you are working with is very important. There are plenty of mediums to use with oil paint just as there are with acrylic paint to get the texture, transparency, and definition that you are trying to achieve. Linseed oil and walnut oil will increase the flow of the paint and soften edges. Citrus thinner will result in a sharper edge, but can dry more chalky. Using equal parts of oil and citrus thinner will result in sharper edges without the chalky appearance. Now it is time to get painting.

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