Size matters : Protein Conditioning (part 1 of 2)
Ok I cannot march on and ignore the chorus! There has been a steady flurry of emails and comments about protein conditioners so I give in and I will answer those questions first.
___________
Avril asks: 'What do protein treatments really do for your hair, in particular eggs? What is it in ApHogee 2 step protein treatment that makes the hair so hard, and how do we benefit from it?'
Kelly asks: 'I thought natural hair was undamaged, do we really need to use protein conditioners?'
Jan asks: 'Can I add amino acids to my hair conditioner to make a protein conditioner?'
____________
Let me start by describing proteins. Proteins are made up from single units known as amino acids(see the diagram below). These amino acids (approximately 20 different types) are arranged joined together through peptide bonds. For simplicity I have drawn just 4. The order and number of amino acids that make up a protein is determined genetically (DNA is wonderful!!). Each protein is made up several hundred to a few thousand amino acids. Again for simplicity I have drawn just a few amino acids.
In order for a protein to be useful for hair, it has to be broken up into smaller segments. This is because proteins such as collagen, wheat protein or keratin are TOO LARGE to be useful. By breaking the protein up into smaller fragments (known as hydrolysed or hydrolyzed protein). Amino acids on the other hand are TOO SMALL.
So why is hydrolysed protein the correct size? This is because to be useful, the protein has to adsorb (yep with a D) to hair. Adsorb means the protein sticks to and forms temporary bonds with the hair. Very large protein simply can't form these bonds reliably. Amino acids on the other hand tend to be very soluble in water so you can expect that you will remove majority of whatever you put on once you rinse your hair. With damaged hair, very small hydrolysed protein (known as peptide fragments) can also be absorbed - yes this can penetrate through to the cortex and be deposited in the hair shaft (Journal of Cosmetic Science, pg69-87, 1993).
Size Matters
Just before moving on, let me just say that even hydrolysed protein has an ideal size for use:
For collagen hydrosylates for example, this is a molecular weight of 2000 (Book reference - Conditioning agents for hair and skin By Randy Schueller, Perry Romanowski).
For wheat hydrosylates this is around 5000-10000 ( Book reference -Principles of Polymer Science and Technology in Cosmetics and Personal Care By Errol Desmond Goddard, James V. Gruber).
The problem is that I have not seen a single protein conditioner actually state the molecular weight. The protein part of eggs (egg white/egg albumin) has a molecular weight of approximately 33000- 40000 (The Journal of Biological Chemistry, pg 189-193, 1939). I can't find a reference for hydrolysed egg albumin size but I would strongly suspect that this molecular weight is too large to be beneficial.
In part 2 tomorrow, I will describe (with diagrams!) exactly how protein can help hair and attempt to answer the question on aphogee (hint - think about egg white and heat)!!
Category Article Hair Science - Protein Conditioner, Reader Questions
Random Posts
-
Pyramid Escape 2 is the next version of Pyramid Escape v1.35 and in these map you can play with all your friends to escape from the pyrami... -
Java is a OO programming language and can use it freely. Java run on the Java virtual machine (JVM). If you like to programming with java fi...
-
I liked posting the future menu last weekend so I will do so again this weekend. Last week mixed micelles won over the behentrimonium (which...
-
Here is an excerpt from Carla's email to me, 'I have just found your blog and spent hours reading it over the past week. I find it v...
-
Here's a lovely announcement from a lady with a lovely name! Sunshine (see her blogs here and here ) is starting a social network for n...