How to formulate a SERUM

Hyaluronic Acid Serum

We have learnt how to formulate a lotion, but what is and how to formulate a serum? πŸ™‚

There are few rules to follow:
1) a serum is usually a very light lotion (this means usually 2%, maximum 4% fats),
2) it is typically fluid
3) it has a very high concentration of ACTIVE INGREDIENTS.
4) it doesn’t have to be heated (actually this is a consequence of the previous points)
5) the function of a serum is to give an extra boost of good ingredients to your skin (just to be clear: the function of a cream is to be emollient and hydrate to the skin… therefore wishing to create “the ultimate hydrating serum” is like expecting to bake the best cake in the world without an oven: if you want hydration, you make a cream… if you want to feed your skin with an extra-boost of vitamins, antioxidants, anti-aging ingredients and sooo on, you make a serum).

How to proceed:
there is still Phase A and Phase BΒ Β but they will be slightly different:

PHASE A – will still contain water, glycerin and a gelling agent (or not, but I will explain this later… so keep reading πŸ™‚ ), but you will have to pay attention to which gelling agent you choose: you need to choose a gelling agent which won’t break down in presence of salts or other tricky ingredients (for exampleΒ carbopol ultrez 21Β is one of these difficult gelling agenta). For instance xanthan gum or hydroxyethylcellulose are good gelling agents for this purpose (in case of hydroxyethylcell. remember the gel is formed only at 70Β° so you will need to heat your water and, only when it is cooled down, proceed in the making of your serum).

PHASE B – the oil soluble ingredients have to be very few: 1.5 – 4% (maximum!). By this I mean that even your oil soluble active ingredients will be counted in the fat percentage of the serum: for example if you desire to add 1% of vitamin E (tocopherol), you include it in your “maximum 4% count” πŸ™‚
But how to behave with these oily substances in order to have a smooth, silky and specially fluid serum? πŸ™‚
You willΒ need different emulsifiers from those which we have used up to now: you will need actually two emulsifiers (one lipophilic at 0.25% and one hydrophilic at higher percentage) which are liquid and don’t need to be heated!
There are many on the market. Actually you could even use a solubilizer to keep together the emulsion (solubilizers are substances which are used to solubilize small small portions of oils into a lot of water: generally they are surfactants. In case you have a solubilizer at home and you want to use it as a hydrophilic emulsifier: add the oily substances of the serum in your becher and, little by little, add drops of the solubilizer until all the solution in your becher becomes milky white. Then add this solubilized oils into your Phase A).
Just for the record: if you don’t add oily soluble ingredients more than 1-1.5%, you don’t even need to add emulsifiers or solubilizers. This is the easiest and most simple way to make a serum πŸ˜€ everything would go in just one phase πŸ˜‰

PHASE C – actually the Phase C could almost be deleted since you can almost always add the active ingredients directly to the Phase A (do not add them only if you use hydroxyethylcellulose as gelling agent because in this case the Phase A has to be heated and active ingredients are thermolabile).

The percentage of ACTIVE INGREDIENTS in a serum can be extremely high.
Sometimes you could even make a serum using an active ingredient as a gelling agent!
An example is the enriched hyaluronic acid serum which you can find HERE: this is also very easy to copy because there is not even the need of adding an emulsifier.

Let me know if I forgot to explain something or you have any questions.
Have a great day! πŸ˜€

63 thoughts on “How to formulate a SERUM”

  1. Thank you so much for writing this! It’s been very difficult to find info on making serum and your article has helped emmensly! I do have a few questions for you. I’m making a brow serum. I would like my ingredients to include water, glycerin, and my performance ingredients-which are all oils. Can I add hylauronic acid serum to this recipe as the emulsifier? If not, what would be some emulsifiers you would recommend? I’m trying to stay as natural as possible but I’m open to all your suggestions. Lastly, if I’m understanding correctly, I will use 70% water & 1.5-4% oils (active oil soluble ingredients.) How much glycerin would I use? One more question, what preservatives would I need to give it a decent shelf life? Any help you can offer would be greatly appreciated.
    Thanks again!


    1. Hello there.
      I never heard of a brow serum so I don’t know exactly what you want to achieve with it but I try to help! πŸ˜€
      1) You shouldn’t start considering how much water you add to the solution: water is, in fact, the last ingredient you should calculate because it is the one which makes your recipe reach 100%: you start planning which ingredients you want to add and, then, you calculate how much water you need to make your recipe reach 100% in order to keep your percentages correct. You could make a serum with 95% water, for example πŸ˜‰
      2) Hyaluronic Acid is not an emulsifier so if you want to use 4% oily active ingredients you will need a real no-heat emulsifier or a solubilizer (for example PGE-10-laurate – which is a very aggressive surfactant/emulsifier. It is not very eco-friendly but you will need very few).
      3) Glycerin doesn’t need to be added in case you use hyaluronic acid gel as gelling agent: glycerin makes things quite sticky and it is a very hygroscopic ingredient (it attracts water) and the same could be said of our hyaluronic acid gel… therefore, personally, I wouldn’t think it is needed but I think if you want you can add 1%

      I have a question:
      Which active oily ingredients you would like to use?
      Because I was thinking that if your aim is to make a very performing serum but you only have oily active ingredients, then I suggest you to make a cream πŸ™‚ so you will be able to increase the % of your oily ingredients and it will still be very performing πŸ™‚


  2. Hi, I’m wondering you state that before adding HEC, the water has to be heated to 70 degree.After adding it into water, does the temperature has to be maintained while mixing it?


    1. no the temperature will naturally cool down while you mix it πŸ™‚
      the 70Β°C are needed in order to make the HEC “open” and gel the water πŸ™‚ but once this happened, you make the gel cool down πŸ™‚ and then you add the heat-sensitive ingredients πŸ™‚


  3. Hyaa I am back again. You’re incredible, how many information I should learn from you πŸ™‚ I always see you amazing DIY & feel happy. For sure I am going to try out one of them & show you. But I will bother you with my questions. About water too 100, I road it hundred time but I am sorry I didn’t get it.

    I have to tell you something. Do you remember my request I think long time I didn’t check it out. I will pass around here and check your new DIY which I am sure it will be beyond the beauty.

    Can I ask you for one thing plz ? I think no more for this intru with you you’re my friend now :). Can you post for us the methods of making the correct way to soluble the cosmetic powder like Vitamin c Glutathione , ALA and AHA ??

    I think the reader should know how to learn the basic things before making any professional DIY, Is I am right ??


    1. Sorry I didn’t remember your request but I never found Vitamin C Glutathione, I don;t know what ALA is and about AHA I always found them in the liquid water soluble form. What form did you find them? πŸ™‚
      Sorry if I couldn’t be of much help.
      ps. Water to 100… you must think that you formulate in percentage. Therefore if you want to add 3% of something to your formulation, you need to adjust the formula in order that all the amounts together reach 100. This is why we calculate water in the end: sum up all the quantities of the other ingredients and eventually calculate how many grams of water are needed to reach 100. This way reaching 100% πŸ˜‰


  4. This is exactly the article I have been searching for!! I am somewhat of a novice at the more complicated DIY skincare. I have been making my basic DIY Vitamin c serum for a while, and started getting into more complex formulas over the last year or so with a hyaluronic acid, B5 serum, BUT I have yet to include oils for fear of separation and most of all, bacterias. I have first-signs-of-aging AND moderately acneic skin and so most products on the market either dry me out (ie more wrinkles) or break me out, or are incredibly expensive, so I feel almost obligated to DIY my own skin care. I also have a little setback in that I live overseas in Spain and so some ingredients are a little hard to find. I do use one website to buy all my potion needs, but could you please explain specific types of lipophilic and hydrophilic emulsifiers?? AND, I just want to make sure <i understand clearly…. if the formula of my serum does not contain more than 1.5% oil/fat, then it is NOT necessary to use an emulsifier?? SO in other words, if I only want to add a few drops of essential oil to my serums, then it's ok to just shake and use??? Thank you in advance and now I am off to scour your blog for more hidden treasures!!


    1. Hello Heather! I am not American and I can assure you, you can buy almost every ingredient inside EU with no problems. There are so many websites that sell ingredients (I have used many from Italy, Spain, UK, France, Germany, Poland…) So nothing to worry about.
      You should worry about bacteria every time there is water, not oils πŸ™‚
      However! I have many recipes I make using usually methyl glucose sesquistearate + cetyl alcohol. You could buy these two or you cpuld buy already “complete” emulsifiers like, for example, olivem 1000, montanov 68 (if I remember the commercial name correctly)! Just surf these websites and read what they suggest for use: if they say to use between 3% to 5%, try using at 4% and then make few experiments to see what’s the difference and what works best for your formulation!
      Don’t be afraid to try and make mistakes! It is all part of the process! πŸ™‚

      Liked by 1 person

  5. Hi. I dont know if i understand correctly, is porlysorbate 20 or 60 the emulsifier to add to the water?


    1. You could use those if you need to add a low percentage of oils.
      Remember to solubilise the oils into the solvent before adding them to the recipe.
      There are many other solubilisers as well πŸ™‚


  6. Yesterday I made one NAG Serum (I tried *lol*), but after one hour it separated in my bottle =((
    If it`s ok for you, please would you look at my recipe ?

    water phase:

    1) water 18,5%
    N-Acetylglucosamine 3%
    Niacinamide 5%
    Sea Emollient 30%
    Licorice Extract 3%
    (here I heated up SEA and water only and hold for 20 min., at about 40-50 C I added NAG, Niacinamide and Licorice)

    2) Oil/ Solvent phase (=) ):


    Vodka 13.5% (I still have to buy ethanol and propylene glycol, had a hard time dissolving my Idebenone in it *ugh*)
    Idebenone 0,5%

    b) Vitamin E Acetate 1,5%
    Oil 10%
    Polysorbate 80 11,5%

    (heated the oil only, than added Vit. E at 45C, than Poly 80. Than I put the vodka stuff a) in b) )

    Than I mixed 2 in 1.

    At the end I added:
    Sclerotium Gum 0,5%
    Geogard 1 %
    Natriumlaktat 2%

    Please don`t laugh ^^

    Was it too much Poly, I remembered I read it has to be 1:1 to oil? And on my face this was so sticky. I still watn to use it up, I just shake it before. It was a small batch, only 30 ml, so do you think it is ok to shake before use? I kinda don`t want to throw it away.


    1. Sclerotium gum needs a heated phase and has to be added to the water phase BEFORE other ingredients. If there are oils, it will not gel properly.
      But all this recipe is a little problematic.
      Too many things!!
      What is “sea emollient”? Is it electrolyte?
      Vodka will destabilyze things and it is very high and you added it to the oil phase (why?). But why would you add idebenone?
      Polysorbate – the problem is that this is not a cream and polysorbate is a solubilizer but it won’t necessarily work as a great emulsifier. You add almost 12% oils to this and call it a serum but it is not. This formula needs a real emulsifier in my opinion. 12% oils is more than any of my face cream have πŸ˜€
      Plus I am not convinced about the 1:1. You should have checked before if the oils + polysorbate were transparent when mixed together. And polysorbate is not a good ingredient to keep on the skin at such a high amount (my opinion here).
      But anyway then you added 12% vodka and created more problems… and then the sclerotium… πŸ˜€

      The thing is: when you formulate you need to have in mind a CLEAR idea of what you want your formula to be for. Mixing every cool active ingredient you can find, is TEMPTING but you should avoid that.
      You should also try to learn how to use ingredients before you formulate with them. πŸ™‚
      So, sclerotium goes in A, take away vodka and the active you wanted to dissolve in it. Change the polysorbate with a real emulsifier and make a cream jf you want 12% oils. Otherwise keep polysorbate but no more than 1.5% oils. The Sea thing sounds like a strong electrolyte but it should be ok with sclerotium.
      Ah Licorice Extract – is it powder? If so, lower it to 0.2%. Powders destroy stability. You already have 5% Niacinamide (but usually it is fine cause it dossolves). About NAG I have no clue: never used, don’t know its suggested concentration or pH or anything.
      Is the pH of all the ingredients compatible with the Niacinamide?


  7. I wrote so much, I`m not sure if you got my comment. I saved it to clipboard meanwhile =) . I don`t want to double-post it.


  8. Hi It’s All in my hands.

    I absolutely have found this blog to be sooo inspiring – you are a wealth of information and so very generous with the help you give to people!

    What I am looking for is a very light facial serum that moisturizes and nourishes the skin in the most natural way possible. Almost like water liquid with oils in it. The following is what I have tried and not succeeded – hoping you can help with this and how I can reformulate/formulate so that it works properly

    Oils used were:
    organic rosehip oil, organic camellia oil, organic pumpkin seed oil, essential oils of french lavender, carrot.

    In a combination of:
    Oil phase = 20 grams of oil, 5 grams of emulsifying Wax N
    Emulsifier used was from

    Water phase = 75 grams of water
    During the preparation state, I kept the two phases separated, the water from the fats (oily based) – heated both to 70 degrees then cooled and started mixing. Afterwards I added the essential oils.

    Three days later, the oil is in a clear jar and has 3 separate sections – the water is on the bottom, oils in the middle and a slight layer of foam remains on the top.

    Is there a possibility you can instruct on how to make a combination like this work! Is it best W/O or O/W-
    As per your comment below, is there need for an emulsifier or can it be done otherwise?
    Also, can you please explain this comment from your blog and how it might be applicable to the above β€œ If you don’t add oily soluble ingredients more than 1-1.5% you don’t need to add emulsifiers or solubilizers”

    Thank you in advance



    1. Hello.
      Thank you πŸ™‚
      Well there are quite some issues here: 20% oils is a lot and it is difficult to make an emulsified cream as liquid as you want it to be, specially with such a high concentration of oils.

      The technic mistakes are these:
      – the emulsifier cannot work alone. I have never used this one, but it needs to be supported by:
      – a gellin agent in the water phase
      – a stabilizer/thickener that will help the phases stay together.
      Every emulsion is unstable so you have to enhance stability. A liquid emulsion is difficult to get and anyway there are specific emulsifiers to get one.
      You also didn’t add a preservative: you should πŸ™‚

      Now to the last thing: when I said that 1-1.5% oils don’t need an emulsifier or a stabilizer, I was only talkin about this kind of formula, as the gel is going to hold up a little (but it won’t emulsify or solubilize anything! However, in this % you must include the fragrance or the essential oil)

      Finally: a facial serum shouldn’t include oils more than few percent. If you want more oils, you want a cream/lotion and not a serum.
      If you want this amount, I would give up the idea of making a liquid lotion to when you are experienced in emulsifying and formulating πŸ™‚
      All the best!!


  9. Ah crap, sorry, but I had to crash close my linux yesterday, so of course file wasn`t saved. I have to write all over again. I will try today, when I`m back at home.
    *Thank you* ^^ (for your detailed answer above to my recipe)

    Liked by 1 person

  10. Hi, uhm I hope you got my post now, cause I can`t see it again, but when I want to re-post it, an error comes up: “Duplicate comment detected; it looks as though you’ve already said that!”


  11. Hi, great resources here!
    I was looking for more info to enable me to make my own serum. I’m really hoping you can help.
    I’d like to make a mix with distilled water (main ingredient), pure L-ascorbic acid (didn’t determine yet), pure vitamin E (up to 5%), glycerine (a few %). I have to add some emulsifier because of vit E but not sure exactly what to do there. I’ll put in ascorbic acid as much as the ph allows (it needs to be around 3). I’ll check this with strips.

    I’m not in EU or USA so I don’t have great choice of lab ingredients available. I have no access to more stable forms of vitamin C and I don’t know how to conserve this, so I’d make a small batch weekly or even every few days and keep in fridge. I barely got a hold of glycerine. Please help me with the ratios.

    Or maybe – this might be smarter – I should just add the vitamin E into my oil mix that I apply at night for skin care and apply this on top of serum – oils will penetrate. But in that case, how to improve the formula, maybe to add 1-1.5% of vitamin E into the water based serum mix? I’d make it weekly anyway and store in fridge in dark bottle, I think vitamin E would help prevent it from oxidizing. Please help me out with this???


    1. Hello.
      Weekly won’t work as vitamin C oxidizes extremely quickly (hours).
      But I do have an article about a vitamin C serum using the ingredients you mention.
      Check “Vitamin C serum” in the search box! πŸ˜‰
      Hope this helped


      1. I really like your recipy on vitamin C! I would have bought the strips anyway so it will work for me. Way better than oxidized store product that costs arm and leg. Disregard my questions there, I’ll write it here – so I only wonder now if I can leave vitamin E overnight after having washed C off, and if I can mix E with my oil of choice? (I apply oils overnight on my skin.)


      2. You can apply later, after washing the Vitamin C off. But if you apply it while vitamin C is on, synergy will happen.
        You can indeed add vitamin E to the oils you apply in the evening!


  12. Hello from Florida,
    I am new in your website and you are amazing.I am trying to catch and learn everything you teach in here as I love to do natural mixes and lately I started just with hyaluronic acid serum from sodium hyaluronate and destilled water. I mix 1/8 tsp of the powder with 2 oz of destilled water. At night I mix a little bit of the serum with a pinch of ascorbic acid and apply it on my face.
    Tell me please if the formula for the hydrating HA serum is ok because I do not have anything to weight on grms. I will start with all your recipes and I would love that you please teach me how to make a serum with HA, matrixil 3000 powderand argerilne. I am a mature woman 55 and want to boost my collagen and diminiss my fine lines. I do not know how to do it and the one I buy it is very expensive. thanks for your help.


    1. Hello! I am using peptides as well, I just never posted a formula with them.
      You NEED to buy a very precise scale, though. Online you can buy one that weights until 0.01 grams for really few euros/dollars (I found one at 7 euros and it still works great).
      You really NEED the scale.
      You can make the serum and add to it matrixyl and argireline, however the latter works better together with another peptide commercially called leuphasyl or a similar name (sorry I am on my phone, can’t check better).
      You also need a preservative, of course.
      Once you have the scale we can talk quantities and proportions πŸ™‚


      1. Good afternoon again,
        Just to tell you that I have the scale and the ingredients plus some B5 and would love that you can help me to make my cream or serum with the matrixil and argeriline and b5 if all of them work together. Maybe a HA with b5 serum to be as a booster ?lots of thanks in advance.


      2. Yes you can make a hyaluronic acid base and then add the peptides and Panthenol to it. That would be a good serum. About quantities: when you have bought the ingredients you should have received data about the range of pH in which they should be used and the percentage of use and you start formulating from this data! πŸ™‚


  13. Thanks so much for this information. I would like to make a serum using Hyaluronic Acid and Vitamin C. The molecular weight of the HA I have is 800-1000 kDa. Could you please give me an idea of the formula for this serum using distilled water and preservative?


  14. The following is my serum formulation.I am not sure it is ok or not?And also the procedures,can put all together and mix them?

    Dehydroxanthan Gum
    Sodium Hyaluronate
    Lactic Acid
    Sodium Phytate
    Benzyl Alcohol


    1. Can you explain what kind of serum you want it to be?
      Can you write next to each ingredient the reason why you are adding it?
      Please also add the percentages, as it is I cannot say anything about this formulation.
      Please also write the molecular weight of Sodium Hyaluronate.


      1. Aqueous serum

        Lactic Acid (active ingredient)—————–[2-5%]
        Alcohol (Ethanol) ———————————[1%]
        Propanediol(viscosity controller)————–[1%]
        Dehydroxanthan Gum(viscosity controller)– [1%]
        1% Sodium Hyaluronate(gelling agent) ——[4%]
        Sodium Phytate(chelating agent) ————–[3%]
        Benzyl Alcohol(preservative) ——————-[1%]
        Water ——————————————[adjust volume to 100ml]


      2. Aqueous serum

        Lactic Acid (active ingredient)—————–[2-5%]
        Alcohol (Ethanol) β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”[1%]
        Propanediol(viscosity controller)————–[1%]
        Dehydroxanthan Gum(viscosity controller)– [1%]
        1% Sodium Hyaluronate(gelling agent) β€”β€”[4%]
        Sodium Phytate(chelating agent) ————–[3%]
        Benzyl Alcohol(preservative) β€”β€”β€”β€”β€”β€”-[1%]
        Water β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”β€”[adjust volume to 100ml]

        Thanks a lot.
        Please kindly check and comment.


      3. Hello!
        The reason why I asked you to write me the aim these ingredients were supposed to have in your serum was to try to understand if you thought about what is this serum going to do.
        So I didn’t mean to read “active ingredient” but more like “moisturizing” or “peeling” or “whitening ingredient” and so on. But it is ok, I will try to tell you why I don’t suggest you to make this serum as it is:

        1) Lactic Acid. This is obviously an acidic ingredient. What pH do you want your serum to have? With Lactic Acid 2%-5% your pH is going to be around… 1 or 2! This is just DANGEROUS and the “benefit” it has for the skin is burning it (seriously burning it!). When adding acid or base ingredients to a cosmetic, you should first ask yourself what pH you want your cosmetic to have and THEN add as much lactic acid until you reach the intended pH (if it is a serum that is supposed to sit on the skin for hours, I wouldn’t go lower than pH 4.5). It also depends what AIM the lactic acid has in your serum: do you want a peeling effect? do you want a moisturizing effect? If you want a peeling effect, low pH is good. If you want a moisturizing effect then you have to buffer the acid with sodium hydroxide in order to obtain sodium lactate, which has great moisturizing properties ( I DON’T DON’T DON’T suggest you to actually do this: it is a dangerous process and you could hurt yourself mixing an acid and a base: you can purchase directly sodium lactate!).
        This said now there is an added issue: you have to check that ALL the other ingredients you are going to add are actually compatible with the 4.5 pH. Is your preservative going to work at that pH? Are other ingredients going to denaturalize? Are some ingredients unstable at that pH?
        2) Ethanol: what is the aim of this 1% ethanol? What benefit does it give to your serum?
        3) Sodium Hyaluronate: did I understand correctly that you add a 1% solution of SH at 4%? Because in this case it is not going to gel anything: it is just a moisturizing ingredient, which is fine, but it won’t do what you wrote you want it to do (you already have the gum which is going to gel anyway so you don’t actually need a second gelling ingredient). This said, there will be an issue with the SH and the acidic environment created by the Lactic Acid (whihc you are NOT going to add at 2-5% anyway, but add it until the pH is 4.5 at most). Sodium Hyaluronate’s pH is around neutral and if it is added to an acidic environment it tends to denaturalize.
        ps. Also depending on its molecular weight, it might actually be that it doesn’t gel a thing, that’s why I asked its molecular weight.
        4) Sodium Phytate: a chelating agent and natural whitener ingredient for toothpaste (not skin, in skin products it doesn’t whiten and it is just a chelating agent). I have never used this ingredient but for what I read it looks like 3% is way too much and its suggested use is between 1%-2%, but I couldn’t understand if this was the suggested use in cosmetics or toothpaste. You also need to ask yourself: is sodium phytate ok at low pH? Because a part of it will become phytic acid. You need to read the information given to you by the reseller of the ingredient.
        5) Last but not least: Benzyl alcohol on its own is not an effective preservative. It is usually combined with other preservatives. You also have to double check what is the pH range where it works. If it doesn’t work at a pH lower than 5.5, for example, you cannot go lower than that with your serum.
        Hope this helped.


  15. Hi I would like to make a serum that will be applied to the face containing:
    CBD oil
    L-asorbic Acid Power
    Hyaluronic Acid powder
    What surfactants do you suggest and what should I mix first? do I need wax pastilles?
    I am new to cosmetics and I am doing for personal use now.
    Thank you so much.


    1. Hello. Please read the comments either in this page or in the Hyaluronic acid serum page regarding the incompatibility of HA and Vitamin C. An oil in a serum is ok at extremely low percentages (0.5%) so it wouldn’t be able to do anything. I’d rather NOT add it to the serum so to not risk having emulsifying issues cause a serum is not not a cream so you don’t add a waxy emulsifier.
      If you don’t add the oil you don’t even need the surfactant.
      About the L-ascorbic acid, it is not stable, you cannot add it to anything unless you use it within a very short time so it would be a waste of Hyaluronic acid.
      So make the simpliest hyaluronic acid serum and use it before or after doing the vitamin C serum you still find here on my blog.


  16. Hi there!
    Thank you for all the useful articles you posted, especially this one.
    I want to make an eye serum and a hair serum and i don’t know what emulsifier to choose to make them very fluid(especially the hair serum)
    The percentage of oils in both of them is around 10% so i can’t use a solubilizer. But what can you recommend me to use? I was thinking maybe cetearyl glucoside combined with xanthan gum for stability and Ethylhexylglycerin + Phenoxyethanol for preservatives but not sure is the right call.
    Would be really grateful if you could help me out.

    Thank you so much!


    1. Hi Marina. The thing is that by default 10% oils will make a cream and not a serum, this means you will have to formulate a cream.
      10% oils in a hair serum are a lot. The solubilizer is a strong strong surfactant but it won’t solubilize 10% oils unless you use really a lot (40%)… But this will make for a probably foamy product that I wouldn’t apply to the hair.
      When you start formulating, try following formulas already made first, then you’ll get a feel of why certain things are not doable πŸ™‚


  17. LOVE your website and FB. Thank You for being a resource to those who wish to learn about making clean personal care products. I have been creating your HA serum for a few years now. It seems to get watery after about 30 days. If I added the Xanthan Gum to this HA formula, would it help it last longer or stay thicker longer? AND will .6 grams (as noted above) of cosgard still preserve the formula if over 30 days?

    Liked by 1 person

    1. Hi Dawn, thank you for the kind words.
      Actually about preserving I haven’t tested the formula. Right now I would say it is a little low, to be honest… But the truth is that you CANNOT KNOW how long your product lasts unless you pay to get it tested in a proper lab.
      You can add xanthan but my rule of thumb is this:
      If a product changes rheology over time it means SOMETHING, so I would make as little product as I can use within the time frame where it won’t change. πŸ˜‰
      Ps. HA tends to liquefy over time, it might also be a pH change (you could check this), however I make maximum 100 grams and store it in the fridge (I am using a broader spectrum preservative at 1% btw)


      1. Hello again! Thanks for your reply. I have a question for you about Cosgard. If I made a double batch would you also add 2x as much of the cosgard? or just a little more? And is there another natural preservative you would recommend to use WITH cosgard as if my serum is out of the refrigerator for 2 months it is getting a white film at the bottom. My friends are not keeping theirs in the refrigerator like me.


      2. I don’t use cosgard anymore but of course if you make double the batch you would have to add double the amount of the preserving system as well.
        Cold and hot temperatures can create issues in stability as they can modify the solubility of certain ingredients.
        So the film on the bottom might be a sediment of some ingredient which isn’t solubilized properly.
        Right now the preserving system I use is phenoxyethanol and ethylhexylglycerine. It is already sold combined and it goes at 1%. The pH should be around 5-5.5


  18. Such an informative post thank you! I’m looking to make a colostrum serum, with the following ingredient list: Water, propylene glycol, colostrum, phenoxyethanol, ethyhexylglycerin

    What would you put in phase A and what would you put in phase B?



    1. I never heard of serums with colostrum. I would worry about being able to preserve the serum.
      I would just gel it with a gelling agent, no need to have different phases if there are no oils πŸ™‚


  19. I have a formula for an antiaging serum but I dont know if the ingredients are in the right percentage, i dont know what im doing wrong, what do you think?

    pomegranate extract 3%
    jojoba oil 20%
    glycerin 15%
    vitamin e 5%
    vitamin c 5%
    coenzyme q10 10%
    biotin 3%
    water q.s
    Tween 20 10%


    1. 20% jojoba ester (not exactly an oil) doesn’t make for a serum. Tween 20 probably isn’t enough to emulsify. Also Vitamin E is extremely high. Safe use for Vitamin E is much lower (0.1%), vitamin C will make your formula go bad in 30 minutes (and 5%… Did you check the pH?).
      Coenzyme q10 use is 0.2%, definitely not 10%.
      Biotin at 3%, I don’t know if that concentration is safe either.
      Glycerin at 15% will make for a VERY STICKY feeling.
      I think you first need to make a few proper formulas that you find around, learn the basics of formulation, read what are the suggested concentration of use of the ingredients you buy… And then attempt to formulate your own πŸ™‚


  20. Thank you for your meaningful blog.
    I’m from Việt Nam and I’m trying to build a serum formula. Can you give me some advices because my serum texture is not thick enough. Or should I use different thickening agent.

    Here is my formula:

    Phase A
    Water (14.7%)
    Niacinamide (2.5%)
    Propylene glycone (5%)

    Phase B
    Water (65%)
    Carbomer-940 (0.1%)
    TEA (0.1%)

    Phase C
    Vitamin E (0.1%)
    Palmarosa essential oil (0.1%)
    PEG-40 (0.3%)

    Phase D
    Glycerin (5%)
    PEG-120 (1%)
    Dimethicone (1%)

    Phase E
    Water (5%)
    Sodium benzoate (0.05%)
    Phenoxyethanol (0.05%)

    First I heated up phase B till 40oC and the added phase A. After that, I added phase C drop-by-drop. Finally, I turned off the heater and added phase D and phase E in turns until the mixture reached the room temperature.

    Hope can hear your advice πŸ₯°πŸ₯°πŸ₯°


  21. So interesting thank you! Can I ask how the 1-1.5% of oil soluble ingredients would mix in with the water based serum? Would they not separate with time? Or does the hyaluronic acid offer mild solubilising characteristics?


    1. They will tend to separate with time, I wasn’t able to find a good solubilizer on retail at the time so I “used up” the solubilizer which was inside the rose water which I used to make the serum in the picture. Now I would still use a solubilizer even for 1%-1.5% of oils.


  22. Hello miss, I send you a message on your Facebook page. I hope you can help and reply in there. Thank you in advance.


  23. So informative, thank you I am trying to formulate a water-based facial serum. Is it ok to combine hyaluronic acid with peptide serum along with aloe vera and glycerin? I would really appreciate your advice.
    Thank you


    1. I don’t think they cannot be combined, however if you are just starting I would rather make 2 or 3 separate serums so to learn how the active ingredients change the feel of the serum and build your knowledge from there (for example some ingredients can make the serum sticky, others might make more of a “plastic” finish… so at least you can learn which does what and can later modulate the percentages)


  24. Wow so much helpful information here .Can you please post your Facebook link so I can follow you


  25. Hello dear,
    I love your posts a lot and the way you explain things. Plz, I’m a rookie in this line, trying to make creams, lotions, serums, etc for my personal use. But I have this ingredients compatibility challenge due to pH levels.
    Plz, how do I use Lysine powder which has pH of 10.5 and Niacinamide powder that has pH of 5.5-6.5? Should I adjust the pH of Lysine powder to 5.5 before adding it to the rest of the formulation?
    Thanks in anticipation of your assistance.


  26. Hello! So informative and helpful!

    Can I allow myself to ask you if I am going in the right direction?

    I am planning to make a natural ingredient spf moisturising serum with the use of lignin as spf ingredient and its abilities as an excellent emulsifier. I am also planning to enhance the serum’s function with natural antioxidants called anthocyanins as spf is best compatible with antioxidants.

    Water phase:
    Water (58,5%)
    Glycerol (5%)
    Xanthan gum (1%)
    Anthocyanin (15%)

    Oil phase:
    MCT oil (0.5%)

    Active ingredients addition:
    Lignin suspension with ethylene glycol (20%)


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s