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The INKEY List Collagen Peptide Serum Versus Biossance Squalane + Copper Peptide Rapid Plumping Serum

The INKEY List Collagen Peptide Serum Versus Biossance Squalane + Copper Peptide Rapid Plumping Serum This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture. This hydrating serum is formulated

The INKEY List Collagen Peptide Serum Versus Biossance Squalane + Copper Peptide Rapid Plumping Serum

This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture.

This hydrating serum is formulated around Squalane and Sodium Hyaluronate to hydrate skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

No concerns

Ingredients Side-by-side

Water

Glycerin

Butylene Glycol

Propanediol

Phenoxyethanol

Hydroxyethylcellulose

Sodium Phytate

Citric Acid

Leuconostoc/Radish Root Ferment Filtrate

Carbomer

Hyaluronic Acid

Sodium Lactate

Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine

Palmitoyl Dipeptide-5 Diaminohydroxybutyrate

Polysorbate 20

Polysorbate 60

Disodium Phosphate

Sodium Phosphate

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Water, Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydroxyethylcellulose, Sodium Phytate, Citric Acid, Leuconostoc/Radish Root Ferment Filtrate, Carbomer, Hyaluronic Acid, Sodium Lactate, Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine, Palmitoyl Dipeptide-5 Diaminohydroxybutyrate, Polysorbate 20, Polysorbate 60, Disodium Phosphate, Sodium Phosphate, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1

Squalane

Sodium Hyaluronate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Copper Tripeptide-1

Acmella Oleracea Extract

Ectoin

Tetrapeptide-30

Palmitoyl Hexapeptide-52

Copper PCA

Panthenol

Sodium Polyglutamate

Camellia Sinensis Leaf Extract

Aloe Barbadensis Flower Extract

Passiflora Incarnata Flower Extract

Melia Azadirachta Leaf Extract

Solanum Melongena Fruit Extract

Curcuma Longa Root Extract

Ocimum Basilicum Flower/Leaf Extract

Coccinia Indica Fruit Extract

Melia Azadirachta Flower Extract

Ocimum Sanctum Leaf Extract

Corallina Officinalis Extract

Polyacrylate Crosspolymer-6

Acacia Senegal Gum

Xanthan Gum

Ethylhexylglycerin

Caprylyl Glycol

Water, Glycerin, Propanediol, Squalane, Sodium Hyaluronate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Copper Tripeptide-1, Acmella Oleracea Extract, Ectoin, Tetrapeptide-30, Palmitoyl Hexapeptide-52, Copper PCA, Panthenol, Sodium Polyglutamate, Camellia Sinensis Leaf Extract, Aloe Barbadensis Flower Extract, Passiflora Incarnata Flower Extract, Melia Azadirachta Leaf Extract, Solanum Melongena Fruit Extract, Curcuma Longa Root Extract, Ocimum Basilicum Flower/Leaf Extract, Coccinia Indica Fruit Extract, Melia Azadirachta Flower Extract, Ocimum Sanctum Leaf Extract, Corallina Officinalis Extract, Polyacrylate Crosspolymer-6, Acacia Senegal Gum, Xanthan Gum, Phenoxyethanol, Ethylhexylglycerin, Citric Acid, Caprylyl Glycol

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
  6. 06Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.
  7. 07Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  8. 08It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  9. 09Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  10. 10A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.
  11. 11Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  12. 12Topically, glycerin does several things at once:
  13. 13Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.
  14. 14Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.
  15. 15This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.
  16. 16Just know very high concentrations (>40%) can feel tacky in low humidity.
  17. 17Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  18. 18Palmitoyl Tetrapeptide-7 (formerly Palmitoyl Tetrapeptide-3) is a synthetic peptide. Its main job is to fight what researchers call "inflammaging".
  19. 19"Inflammaging" is the slow, low-grade chronic inflammation that quietly breaks down collagen as we age.
  20. 20This ingredient calms down a specific inflammation signal in your skin cells (called IL-6). When left unchecked, this signal triggers enzymes that break down collagen and elastin.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side

04

Ask the journal

Related questions

01What if you see no results after several weeks

First, ensure you are applying correctly and consistently. Sporadic use will not deliver results. Second, verify your expectations are realistic. Peptides produce gradual improvements, not dramatic transformations. Third, consider whether other factors are counteracting benefits. Sun exposure without protection, smoking, poor sleep, and dehydration all undermine skincare efforts. If you have used the product correctly for three months without any noticeable improvement, the serum may simply not work for your skin chemistry. Individual response to cosmetic ingredients varies, and no product works universally. Consider trying a different peptide formulation or alternative anti-aging active.

Source · seekpeptides.com