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The INKEY List Collagen Peptide Serum Versus Timeless Skin Care Matrixyl 3000 Serum

The INKEY List Collagen Peptide Serum Versus Timeless Skin Care Matrixyl 3000 Serum This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated around Palmitoyl

The INKEY List Collagen Peptide Serum Versus Timeless Skin Care Matrixyl 3000 Serum

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

This anti-aging serum is formulated around Palmitoyl Tripeptide-1 and Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

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

Aloe Barbadensis Leaf Extract

Benzyl Alcohol

Dehydroacetic Acid

Water, Glycerin, Butylene Glycol, Carbomer, Polysorbate 20, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Aloe Barbadensis Leaf Extract, Hyaluronic Acid, Benzyl Alcohol, Dehydroacetic Acid

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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

Carbomer 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.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 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.

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.

Hyaluronic acid (HA) is a glycosaminoglycan (basically a long sugar chain) that your skin already makes on its own. In your skin, HA lives in the extracellular matrix and acts as the body's moisture reservoir.

Topically, HA is a humectant that binds water and helps skin look more plump, smooth, and hydrated.

The only catch is that HA isn't a single thing; it actually comes in a wide range of molecular weights (~50 - 2,000+ kDA) and size matters.

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

This is why the best HA serums blend the two sizes together so you get the best of both worlds.

The majority of cosmetic HA is produced by bacterial fermentation, typically using Streptococcus or Bacillus strains. Typical use levels in skincare sit around 0.1-2%.

A clinical study using a 0.2% low-molecular weight HA gel showed improvement in facial seborrheic dermatitis with excellent tolerance.

These are some other common types of Hyaluronic Acid:

Palmitoyl Tetrapeptide-7 (formerly Palmitoyl Tetrapeptide-3) is a synthetic peptide. Its main job is to fight what researchers call "inflammaging".

"Inflammaging" is the slow, low-grade chronic inflammation that quietly breaks down collagen as we age.

This 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.

Clinical testing showed statistically significant improvements in:

Studies also found the more of this ingredient used, the more your skin produces Collagen I, fibronectin, and hyaluronic acid.

You'll likely see this ingredient paired with Palmitoyl Tripeptide-1 in the well-known Matrixyl 3000 complex for enhanced anti-aging effects.

A 3% concentration applied twice daily for two months showed meaningful skin rejuvenation results in clinical panels.

Fungal acne note: Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

Palmitoyl Tripeptide-1 (aka Pal-GHK) is a synthetic signal peptide made of three amino acids attached to palmitic acid.

That fatty acid attachment is the key: it boosts the peptide's ability to penetrate the skin barrier. This puts it closer to the dermal cells where it can actually make a difference.

Once there, it acts as a matrikine, a signaling peptide that prompts fibroblasts to produce more collagen, fibronectin, and hyaluronic acid.

In vitro studies show it can boost collagen production in skin cells even when UV-damaged skin samples were treated with it at a tiny concentration (it almost fully restored dermal collagen at 5ppm). It achieved this at 100x lower concentration than retinoic acid, which needed 500 ppm to do the same thing.

Human clinical data is promising, but modest:

A study of 23 female volunteers found a small but statistically significant increase (~4%) in skin thickness after treatment at 4 ppm.

A separate small trial of 15 women showed statistically significant reductions in wrinkle length, depth, and skin roughness after applying it twice daily for four weeks.

You'll likely see Pal-GHK paired with Palmitoyl Tetrapeptide-7 as part of the Matrixyl 3000 complex.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

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. 03Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  4. 04Topically, glycerin does several things at once:
  5. 05Your 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.
  6. 06Aquaporin-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.
  7. 07This 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.
  8. 08Just know very high concentrations (>40%) can feel tacky in low humidity.
  9. 09Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  10. 10Water. 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.
  11. 11So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
  12. 12You'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!
Source · skinsort.com
02

Product index

Related product references

Product

The Inky List Collagen Peptide Serum

The Inky List Collagen Peptide Serum The Inky List Collagen Peptide Serum ingredients explained: Water (Aqua/Eau), Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydroxyethylcellul…

Source: incidecoder.comView reference →

Product

Madara Derma Collagen Peptide Serum

Madara Derma Collagen Peptide Serum Ingredients in Madara Derma Collagen Peptide Serum explained: benefits, concerns, and detailed analysis of 28 ingredients including Aloe Barbadensis Leaf…

Source: skinsort.comView reference →
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