Alpha-Arbutin and dark spots

Anyone has experience on alpha-arbutin and dark spots, please share your experiences. Thanks in advance. 
Which ingredients work well with alpha-arbutin?

thanks

Comments

  • Doesn’t do much
  • PharmaPharma Member, Pharmacist
    First: I don't speak from experience regarding arbutin in cosmetics but from experience as a pharmacist with a PhD in pharmacognosy/phytochemistry: keep in mind that some things are true for both, others are quite different between scientific lab-work and real life ;) .

    Arbutin will hydrolyse under acidic conditions to form glucose and the more reactive hydroquinone especially at elevated temperatures. Arbutin and even more so hydroquinone are susceptible to oxidation (benzoquinone is formed) already under slightly alkaline conditions and/or UV irradiation which cause their degradation sometimes within minutes to form a dark coloured polymeric substance. This effect is pronounced when nucleophilic substances such as thiols (e.g. cysteine) and to a lesser extent primary amines (rare in cosmetics) and even certain alcohols (abundant in cosmetics) are present.
    A slightly acidic environment (pH about 5-6) and room temperature keeps the hydroquinone moiety safe from degradation and isn't too acidic to cause arbutin hydrolysis but acidic enough to prevent chemical reactions with other ingredients.

    A problem with hydroquinone can be that it may start an autocatalytic oxidation of itself and of ascorbic acid if the latter is present at active concentrations (>1%) rather than just as antioxidant for "preservation" (~0.1-0.2%). Mind, arbutin & high ascorbic acid is a common skin bleaching combination. The phenomenon of hydroquinone and ascorbic acid degradation isn't always predictable but can cause dark colours either homogeneously throughout the product or as spotty/patchy appearance due to the vicious cycle randomly starting in just a few places where by bad luck the reaction is kicked off. This reaction is again pronounced under high temperature, high alkalinity and UV-irradiation and "gets exponential" when (pro-)oxidants such as benzoyl peroxide or heavy metal ions for example from iron oxides are present. Notably, this degradation requires oxygen! EDTA and other strong metal chelates can help dealing with trace amounts of iron and vacuum-mixing and a non-transparent, airless pump dispenser should be of great advantage too. But sadly, the developing colour is visible at really low amounts and completely avoiding oxygen is nearly impossible. Avoiding susceptible ingredient combinations would be the better way to go.

    Besides: A proper ingredient listing of your spotty product might shed more light on your issue ;) .

    F*** errr... EDIT: Today isn't my best day ;( . I just realised that I misunderstood your question and wrote the whole thing in vain :( .

    Here's the useful part: Experience in the pharmacy with dark spots says that arbutin alone doesn't suffice. Combinations of hydroquinone with other things might but therein it's unpredictable to know which ingredient does what and to which extent. Besides, hydroquinone is skin permeable and "bleaches" whereas arbutin is said to inhibit melatonin formation and is very unlikely to reach high enough concentrations in the deeper areas of the skin where true pigment spots are produced.
  • DtdangDtdang Member
    @Pharma, thanks for Comment
  • @Pharma, thank you very much! It's very useful comment. I knew that aplha arbutin should be formulated within neutral pH, but I didn't know how important it is. I also didn't know about metals (I always add EDTA just in case but here it's justified).

    I am speaking as someone who used and wasn't impressed with the result. Probably anecdotal evidence but it seems to me that it prevents skin from getting darker after sun exposure, but it doesn't lighten what's already there. I guess it might be true provided it's mechanism of work.
  • DtdangDtdang Member
    @ngarayeva001 and @Pharma, I just found the information said that ethyl ascorbic acid and alpha-arbutin are good for dark spots. Do you ever experience on them?
  • I don't have experience with ethyl ascorbic acid because it's impossible to find it on the DIY market (please let me know if I am wrong). If you can find it, make sure it shouldn't be formulated within low pH (see Pharma's explanation on the Ph above). LAA serums should be formulated at a low pH to be active.
  • PharmaPharma Member, Pharmacist
    Lipophilic ascorbic acid derivatives such as ascorbyl palmitate, tetrahexyldecyl ascorbate and also ethyl ascorbic acid penetrate skin better/deeper than pure ascorbic acid. In addition, the latter two are without charge and are "inactive", they require activation by cellular enzymes to become active vitamin c and are therefore said to be superior for above application. I have zero experience with ethyl ascorbic acid and only a scientific one regarding ascorbyl palmitate (I love that stuff!). Theoretically, ethyl ascorbic acid should not interfere with anything in a cosmetic preparation, is the smallest molecule of all the "prodrug" derivatives and hence, in theory, the best of 'em all ;) .
  • ngarayeva001ngarayeva001 Member
    edited May 22
    Oh it’s lipophilic! I didn’t know that. Very interesting ingredient. I wish I could buy it. Have some experience with tetrahexyldecyl ascorbate. I am not too impressed to be honest. 
  • DtdangDtdang Member
    @Pharma, Thank you so much.
    Would you please explain more details about cellular enzymes?
    I hope that alpha-arbutin + ethyl ascorbic acid can help dark spots

    Thanks again
  • DtdangDtdang Member
    @pharma, ngarayeva001
    My hope is that:
    Alpha arbutin & Ethyl ascorbic acid give dual approach by soothing skin to quell the inflammatory mediators that lead to upregulation of tyrosinase,
     while also acting as a tyrosinase inhibitor to reduce melanin production.
  • DtdangDtdang Member
    @pharma, ngarayeva001
    Another ingredient called retinol. It has superior benefits of anti-aging.
    Is there any chemical reaction between retinol + ethyl ascorbic acid + alpha-arbutin?

    Thanks in advance

  • PharmaPharma Member, Pharmacist
    @Dtdang Ascorbic acid is not just an antioxidant (a reducing agent) but also a so called conjugated acid. The hydroxy group(-s) responsible for both actions can either be esterified with ethanol or with a carboxylic acids forming a fairly stable acid anhydride. This feature is quite exceptional but way off the point :) .
    Anyway: Such a modified ascorbic acid is no longer acidic nor an antioxidant, it's "dormant" and doesn't degrade or react before reaching the interior of a cell. Once inside a cell (the modification makes it lipophilic, oil-soluble and hence cell permeable) it meets different enzymes, mostly lipases, which cleave off the protecting group liberating active ascorbic acid which becomes trapped within the cell where it can work its magic.

    Retinol profits from the antioxidants which render it more stable. Else, there shouldn't be any negative interactions.
  • DtdangDtdang Member
    @Pharma, thank you so much. I understand it now. 
  • There is one thing to consider. Retinol is a skin sensitiser. As well as LAA in high concentrations. I wouldn't recommend to have them in the same routine unless you are working with deriatives as mentioned above.
    I saw formulas with encapsulated retinol and tetrahexyldecyl ascorbate.
  • DtdangDtdang Member
    @ngarayeva001 what does LAA mean? I don’t understand it. Would you explain.
  • ngarayeva001ngarayeva001 Member
    edited May 24
    L-Ascorbic Acid. All derivatives get converted into LAA in the skin.
  • DtdangDtdang Member
    Thanks 
  • DtdangDtdang Member
    @ngarayeva001 thanks 
  • DtdangDtdang Member
    @Pharma, I have question: the modified ascorbic acid such as ethyl ascorbic acidenter the cell. After enzyme, ascorbic acid is off to protect the cell. Where does ethyl go?
    thank you in advance.

  • PharmaPharma Member, Pharmacist
    @Dtdang That's ethanol, your cell gets drunk :smiley: . Naw, likely not drunk because that small quantity of ethanol gets fully metabolised.
  • @Pharma, now I will be imagining drunk cells all day long :smiley:
    I want to thank you for your comments. It's great to have someone who knows the science behind processes and is willing to share this knowledge with others (your previos comments on effect of the pH on alpha arbutin was very useful).
  • DtdangDtdang Member
    @Pharma, @ngarayeva001 thank you so much.
     I will have the results: alpha-arbutin vs. alpha-arbutin + ethyl ascorbic acid soon. I will let you know.

    @Pharma, I have a lot of basic questions. Would you please help me? You have great knowledge and sharing. I again appreciate you a lot.
    our skin doesn’t absorb water? Only oils with small molecular weight can be absorbed through our skin? Because Most active ingredients are water soluble, therefore we need to choose oils(easy absorbed) and emulsifiers with small molecular weight => cream is easy to absorb to our skin?
  • I don't think you want emulsifier to penetrate your skin. Read about the 500 dalton rule and research propylene glycol and dimethyl isosorbide. Both are penetration enhancers. Having said that, I would be very careful, as the barrier function of our skin exists for a reason.
  • DtdangDtdang Member
    @ngarayeva001, thanks 
    can you explain the penetrating processes of cream to skin?

  • DtdangDtdang Member
    @ngarayeva001, questions:
    so what happens when cream was applied to the skin? 
    The emulsifiers combine the water and oils . The water and oils may contain the active ingredients. I read 500 dalton rules. 
    Thanks
  • PharmaPharma Member, Pharmacist
    quote: our skin doesn’t absorb water? Only oils with small molecular weight can be absorbed through our skin? Because Most active ingredients are water soluble, therefore we need to choose oils(easy absorbed) and emulsifiers with small molecular weight => cream is easy to absorb to our skin?
    It does absorb water in a way, just stay in the bath tub long enough and you'll notice. Small molecular weight oils will absorb into the outer layer of the skin and will then get stuck. Small compounds follow certain rules (Lipinski's rule of five) which aren't a scientific fact but based on observation and originally made for orally available pharmaceutical drugs. Skin penetration is more regulated and hence, it's rather a rule of three and/or a higher required lipophily. Though, too lipophilic (i.e. triglycerides) will have the molecule get stuck in the lipid layers of the skin because they completely lack water solubility and there's quite a lot of water in our bodies. On the other hand, some molecules like heparin contradict all rules and still show transdermal bioavailability.
    As mentioned by @ngarayeva001, some small molecules such as DMSO, laurocapram, urea, medium chain fatty acids, or isopropyl myristate may serve as resorption enhancers, rendering a cosmetic product into a pharmaceutical drug.

    Furthermore, most creams aren't absorbed but adsorbed. Although leaving a dry afterfeel, lipids stay on the skin often in a way like water in a sponge.

    Which enhancer you want to use depends on the active ingredient. Too good a solvent will make the active stay in the solvent rather than going into the skin. Another consideration is that resorption enhancers aren't necessarily solvents but usually show additional effects and may be chaotropic substances, cause swelling of the stratum corneum, and/or alter the lipid layer or intercellular protein organisation. All these effects reduce the skin's protective function and make transcutaneous flux easier (some literature as example: CLICK ME). Again, it all depends on the compound you wanted to get through the skin.

  • @Pharma, apologies a bit offtopic, I read (not very reliable source) that water in oil emulsions are better at delivering actives. I wonder if there’s any scientific backing for such a claim.. Maybe this claim comes from the fact that most topical drugs come in form of ointments?
  • PharmaPharma Member, Pharmacist
    edited May 31
    It depends on the used drug. Ointments show better occlusion and that's about the only real difference. Because cutaneous resorption is usually only possible for lipophilic molecules, some oil as solvent may be advantageous. Also, many dermal preparations are meant to treat injured skin and that one often lacks it's barrier function, an ointment is hence better suited than a light cream.
    A different story would for example be salicylic acid or lidocaine: Both can be dissolved in water in their salt form but skin penetration of charged molecules (salts) is poor. Dissolving them in a polar oil seems logical but shows less effect/penetration than suspending them in mineral oil. The trick here is that oil-dissolved salicylic acid and lidocaine love being dissolved and hence stay in the solvent/oil rather than being pushed into the skin as it happens when using occlusive vaseline.

    Besides, ointment isn't usually used as scientific nomenclature and there's a lot of mumbo-jumbo and marketing involved. An ointment might come as light cream, high internal phase oil in water emulsion, or as tough zinc oxide containing anhydrous salve. The pharmaceutical terms which describe the physical state and composition of the preparations aren't usually what customer think it is.
  • ngarayeva001ngarayeva001 Member
    edited May 31
    I also thought they must be just more occlusive and that’s the ‘magic’. Thank you!
  • DtdangDtdang Member
    Here after 4 days, apply cream before going to bed.
    cream with only alpha arbutin: nothing improved 
    cream with alpha arbutin + ethyl ascorbic acid: skin tone brighten and more even + fading dark spots about 20%.
  • ngarayeva001ngarayeva001 Member
    edited June 2
    What tools did you use to take the
     measurements?
  • DtdangDtdang Member
    Just vision check on the picture before applying the cream and after 4 days (taking pictures)
    next times checking is 8th day.
  • DtdangDtdang Member
    Molecular weight of alpha arbutin is around 272 g/mol = 272 da

  • DtdangDtdang Member
    Molecular weight of ethyl ascorbic acid is 204 da
    So both of them have molecular weight less than 500 da
  • DtdangDtdang Member
    @ngarayeva001, do you know any tools to measure? I just do by vision
  • DtdangDtdang Member
    After research, I found that
    when applying cream to the skin, there are three possible ways:
    1) if the ingredients < 500 daltons , they are absorbed through skin. 
    2) if the ingredients > 500 daltons, they may be absorbed through the glance
    3) if the ingredients > 500 daltons, they may be absorbed between the cells 
    most of extra oils will be staying on the surface of the skin to perform occlusive.
    it takes about 30 minutes for absorption 

  • Unfortunately it's not as easy as being below 500 daltons. There are many other factors. Having said that I am in a doubt you can see any result in 4 days. Skin renewal cycle takes 28 days in average. Apha arbutin doesn't make skin lighter it prevents it from getting darker after sun exposure. Not sure how ethyl ascorbic acid works, but LAA also takes some time to demonstrate any visible result. The only skincare that gives visible result overnight are AHA peels. And even that isn't measurable.
  • PharmaPharma Member, Pharmacist
    Or bleaching products such as benzoyl peroxide ;) .
    Ascorbic acid may in fact cause bleaching but I don't know how many % would have to be used to do the trick and I'm not sure if it also works on dark spots or just stains. I did manage to remove stains I got from handling colours and chemicals with the aid of ascorbyl palmitate but it took a lot and didn't work as well as intended. Also, said spots were susceptible to decoloration by antioxidants.
  • MarkBroussardMarkBroussard Member, Professional Chemist
    You're not going to see any noticeable results from using Alpha Arubtin within a 2 to 3 months, at best.  So, any improvement you are seeing after only 4 days is an optical illusion ... we all like to self-delude that our skin care products make more difference than they really do when we look in the mirror.

    If you want something to work faster than that, I would recommend applying a Trichloroacetic Acid peel once weekly, combined with serum containing a  cocktail of melanin inhibitors:  Alpha Arbutin, Kojic Acid, Daisy Extract, Niacinamide, Bearberry Extract, Mulberry, Licorice Root + 8% Glycolic Acid 
    Chemist/Microbiologist formulating in the Organic & Naturals arena under ECOCert/Natural Products Assn/Whole Foods/National Organic Program guidelines focused skincare & haircare products. 

    See website for details www.desertinbloomcosmeticslab.com
  • ngarayeva001ngarayeva001 Member
    edited June 3
    TCA and Glycolic in the same routine sounds a bit drying.
  • MarkBroussardMarkBroussard Member, Professional Chemist
    Not at all ... it greatly accelerates cell turnover.  Nothing "drying" about it as you are rapidly replacing new skin cells.
    Chemist/Microbiologist formulating in the Organic & Naturals arena under ECOCert/Natural Products Assn/Whole Foods/National Organic Program guidelines focused skincare & haircare products. 

    See website for details www.desertinbloomcosmeticslab.com
  • DtdangDtdang Member
    @MarkBroussard, thanks.
    there Is problem with glycolic acid that for maximum effect of glycolic acid, the pH must be around 3.8 and fda allows < 10% concentration and its side effect on exposing to sun light or hot temperatures.
  • DtdangDtdang Member
    Another is usually stirring glycolic with NaOH
    i tried to dilute glycolic but the pH is changing little.
  • DtdangDtdang Member
    The results are surprised 
    even skin tone
    dark spots reduced but not evenly 
    several small fading spots in dark spot have same color as normal color skin

    so they look not nice
  • MarkBroussardMarkBroussard Member, Professional Chemist
    @dtdang:

    You're going to have to use a base (20% NaOH solution) to increase the pH of the Glycolic Acid mixture to get the pH to the proper level.  It's a process ... as I said before, it will take a couple of months of daily use to fade the spots. 
    Chemist/Microbiologist formulating in the Organic & Naturals arena under ECOCert/Natural Products Assn/Whole Foods/National Organic Program guidelines focused skincare & haircare products. 

    See website for details www.desertinbloomcosmeticslab.com
  • DtdangDtdang Member
    The results;
    even skin tone : nice
    dark spots: 80% 
    overall: nice
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