Biotinoyl Tripeptide-1 (Biotinyl-GHK)

1. Overview

Biotinoyl tripeptide-1 (also known as biotinyl-GHK or biotin-GHK) is a synthetic cosmeceutical peptide created by conjugating biotin (vitamin B7/vitamin H) to the naturally occurring tripeptide GHK (glycyl-L-histidyl-L-lysine). With a molecular weight of 567.68 g/mol and the INCI designation Biotinoyl Tripeptide-1, this compound was designed to combine the follicle-supportive and ECM-stimulating properties of the GHK tripeptide with the keratin-strengthening effects of biotin for targeted hair growth and eyelash enhancement applications [1][2][3].

The rationale behind the biotin-GHK conjugation is twofold. The GHK tripeptide, first discovered by Loren Pickart in 1973 [1], is a well-characterized matrikine that stimulates collagen synthesis, promotes wound healing, and modulates gene expression in dermal and follicular cells [2][3]. Biotin, meanwhile, is a water-soluble B vitamin that serves as a cofactor for carboxylase enzymes involved in fatty acid synthesis, amino acid metabolism, and gluconeogenesis -- processes essential for keratin production and hair shaft integrity [5][6]. By chemically linking these two molecules, biotinoyl tripeptide-1 achieves targeted delivery of both bioactive components to the hair follicle microenvironment.

Ex vivo studies have demonstrated that biotinoyl tripeptide-1 localizes specifically to the peri-piliar zone of isolated human hair follicles and stimulates keratinocyte proliferation at the hair bulb, increasing hair growth by 58% at 2 ppm and 121% at 5 ppm compared to untreated controls. The conjugated form also offers practical advantages over free biotin in topical formulations, including superior pH stability and sustained release of bioactive components for up to 12 hours versus 2-4 hours for unconjugated biotin.

Biotinoyl tripeptide-1 is classified as a cosmetic ingredient and is commercially available in numerous hair care products including serums, lotions, shampoos, and lash enhancement formulations. It is not approved as a pharmaceutical for any indication, and the clinical evidence base remains preliminary, consisting primarily of manufacturer-sponsored studies and small-scale clinical observations [8].

Molecular Weight

567.68 g/mol

Molecular Formula

C24H37N7O6S

Structure

Biotin-Gly-His-Lys (biotin conjugated to GHK tripeptide)

CAS Number

299157-54-3

INCI Name

Biotinoyl Tripeptide-1

Typical Concentration

1-3% in cosmetic formulations

Routes Studied

Topical only (serum, lotion, mascara)

FDA Status

Not approved as drug; used as cosmetic ingredient (INCI listed)

Key Commercial Products

Found in various hair growth serums and lash enhancement products

2. Mechanism of Action

Biotinoyl tripeptide-1 exerts its effects through multiple complementary mechanisms that derive from its dual biotin-GHK structure.

Keratinocyte Proliferation in the Hair Bulb

The primary documented mechanism of biotinoyl tripeptide-1 is stimulation of keratinocyte proliferation at the base of the hair follicle. This is evidenced by increased expression of Ki-67, a nuclear protein marker of active cell division, in hair bulb keratinocytes treated with the peptide. Enhanced keratinocyte proliferation at the hair matrix directly translates to increased hair shaft production and faster hair growth.

Basement Membrane Protein Synthesis

Biotinoyl tripeptide-1 selectively stimulates synthesis of two key structural proteins of the dermal-epidermal junction and follicular basement membrane:

• Laminin-5 (laminin-332): A major basement membrane glycoprotein that forms anchoring filaments connecting the epidermis to the dermis. In the hair follicle, laminin-5 is critical for anchoring the hair shaft within the outer root sheath, and its deficiency is associated with poor hair attachment and increased shedding.

• Collagen IV: The primary structural collagen of basement membranes. Enhanced collagen IV production strengthens the structural foundation of the hair follicle, supporting optimal follicle architecture during the anagen (growth) phase.

By increasing both laminin-5 and collagen IV, biotinoyl tripeptide-1 strengthens the physical anchoring of the hair shaft within the follicle, potentially reducing hair shedding and improving hair retention [10][12].

GHK-Derived ECM Remodeling

The GHK component of biotinoyl tripeptide-1 retains the matrikine properties of the parent tripeptide, including stimulation of extracellular matrix protein synthesis [2][4]. The GHK peptide has been extensively characterized for its ability to:

• Stimulate collagen types I and III synthesis in fibroblasts [4][10]
• Promote glycosaminoglycan and proteoglycan production [10]
• Modulate integrin expression for enhanced cell adhesion [18]
• Support dermal papilla cell function and viability [17]

Biotin-Mediated Keratin Support

The biotin component serves as a cofactor for carboxylase enzymes essential for keratin protein synthesis [5][6]. Biotin deficiency is associated with hair loss and brittle nails, and supplementation has been shown to improve hair quality in deficient individuals, though evidence for benefit in biotin-sufficient individuals is limited [6]. The chemical conjugation to GHK provides targeted delivery of biotin to follicular cells rather than systemic supplementation.

Sustained Release Advantage

The chemical conjugation in biotinoyl tripeptide-1 confers a sustained-release pharmacokinetic profile. The conjugated form provides prolonged biological activity for up to 12 hours compared to 2-4 hours for standard free biotin applied topically. This extended duration of action may improve efficacy in once-daily topical application protocols.

3. Researched Applications

Hair Growth Stimulation

Evidence level: Preliminary (ex vivo, small clinical studies)

The primary researched application of biotinoyl tripeptide-1 is stimulation of hair growth. Ex vivo studies using isolated cultured human hair follicles demonstrated dose-dependent hair growth increases of 58% (at 2 ppm) and 121% (at 5 ppm) compared to untreated controls. The peptide localized specifically to the peri-piliar zone, confirming targeted action at the follicular level.

Androgenetic Alopecia and Telogen Effluvium

Evidence level: Preliminary (open-label study with multi-ingredient formulation)

In a 6-month open-label clinical study, 56 patients with androgenetic alopecia (AGA) and telogen effluvium were treated with a topical hair lotion containing biotinoyl tripeptide-1 among other active ingredients. Results showed significant increases in total hair count and anagen (growing) hairs, with patients reporting a 79% decrease in perceived hair loss. However, as a multi-ingredient formulation, the specific contribution of biotinoyl tripeptide-1 cannot be isolated from these results.

Eyelash Enhancement

Evidence level: Preliminary (small clinical study)

Biotinoyl tripeptide-1 has been evaluated in lash enhancement formulations. A clinical study using mascara containing 2% biotinoyl tripeptide-1 (in a commercial formulation) demonstrated 17% increase in lash length and 19% increase in lash thickness after 30 days of daily use. These results support the peptide's role in promoting lash growth through follicular keratinocyte stimulation.

Hair Follicle Anchoring and Shedding Reduction

Evidence level: Preliminary (in vitro)

The stimulation of laminin-5 and collagen IV synthesis suggests biotinoyl tripeptide-1 may reduce hair shedding by strengthening the physical anchoring of hair shafts within follicles. This mechanism is particularly relevant for diffuse hair thinning conditions where weakened follicle attachment contributes to excessive hair loss.

4. Clinical Evidence Summary

The evidence base for biotinoyl tripeptide-1 is classified as preliminary for several important reasons:

1. No independent peer-reviewed monotherapy trials: Published clinical studies have evaluated biotinoyl tripeptide-1 only as part of multi-ingredient formulations. The independent contribution of the peptide cannot be determined from existing data.

2. Manufacturer-sponsored data: Much of the available efficacy data originates from the ingredient manufacturer's technical files rather than independent academic research.

3. Small sample sizes: Available clinical studies involve relatively small numbers of subjects and lack rigorous randomization and blinding.

4. Ex vivo foundation: The strongest evidence for biotinoyl tripeptide-1 as a standalone ingredient comes from ex vivo hair follicle culture studies, which provide useful mechanistic insight but do not always predict clinical outcomes.

Despite these limitations, the direction of evidence is consistently positive, and the dual mechanism (GHK-mediated ECM stimulation plus biotin-mediated keratin support) has a sound biological rationale [2][3][5].

5. Dosing in Research

All dosing data for biotinoyl tripeptide-1 pertain to topical application. No injectable, oral, or other systemic route of administration has been studied. The concentrations below reflect those used in published studies and manufacturer guidelines.

Key formulation observations:

• Recommended cosmetic concentration range is 1-3% in leave-on formulations.
• Ex vivo efficacy was demonstrated at 2-5 ppm (parts per million), which corresponds to very low absolute concentrations.
• The ingredient is compatible with a wide pH range and can be incorporated into aqueous and emulsion formulations.
• For hair applications, leave-on formulations (serums, lotions) are preferred over rinse-off formulations (shampoos) due to longer contact time with the scalp.

6. Safety and Side Effects

Topical Safety Profile

Biotinoyl tripeptide-1 has demonstrated a favorable topical safety profile in available studies:

• No serious adverse events have been reported in published clinical studies using formulations containing biotinoyl tripeptide-1.
• No known allergenic or sensitizing properties have been documented in the published literature.
• The ingredient is generally well-tolerated on the scalp and periocular area (for lash applications).
• The Environmental Working Group (EWG) has assigned a favorable safety rating for cosmetic use of biotinoyl tripeptide-1.

Precautions

• Eye contact: As with most cosmetic peptides, direct eye contact should be avoided as irritation may occur.
• No systemic data: No safety data exist for injectable or oral administration. All safety data pertain exclusively to topical use.
• Pregnancy and lactation: No specific studies have evaluated safety during pregnancy or breastfeeding.
• Biotin interference with lab tests: High-dose biotin supplementation is known to interfere with certain immunoassays (troponin, thyroid hormones). While topical biotinoyl tripeptide-1 is unlikely to achieve systemic biotin levels sufficient to cause this interference, awareness of this issue is warranted [6].

Comparison with Other Hair Growth Ingredients

Biotinoyl tripeptide-1 lacks the common side effects associated with conventional hair loss treatments such as minoxidil (scalp irritation, hypertrichosis, initial shedding) and finasteride (sexual side effects, mood changes) [7][15]. However, it is important to note that the evidence base for biotinoyl tripeptide-1 is far smaller, and rare adverse effects may not yet have been identified.

7. Regulatory Status

• INCI Name: Biotinoyl Tripeptide-1 (listed in the International Nomenclature of Cosmetic Ingredients)
• Classification: Cosmetic ingredient, not a pharmaceutical
• FDA (United States): Not approved as a drug for any indication. As a cosmetic ingredient, it is not subject to pre-market drug approval.
• EU (European Union): Permitted in cosmetic formulations under EC Cosmetics Regulation 1223/2009.
• No drug approval: Biotinoyl tripeptide-1 has not received approval as a pharmaceutical for hair loss or any other condition in any regulatory jurisdiction.
• Raw material availability: Available from multiple peptide synthesis suppliers as a raw cosmetic ingredient, with commercial trade names including SpecPed BT1P (Spec-Chem Industry).

8. Pharmacokinetics

Biotinoyl tripeptide-1 is designed exclusively for topical application, and its pharmacokinetic profile reflects the behavior of a biotin-peptide conjugate on skin and hair follicle surfaces.

Topical application and follicle targeting. The biotin conjugation serves a dual purpose: it enhances the stability of the GHK tripeptide in topical formulations and facilitates targeted delivery to the hair follicle microenvironment. Ex vivo studies demonstrated specific localization of biotinoyl tripeptide-1 to the peri-piliar zone of isolated hair follicles, confirming preferential accumulation at the target site rather than diffuse distribution across the skin surface.

Biotin conjugation and sustained release. A key pharmacokinetic advantage of biotinoyl tripeptide-1 over free biotin and unconjugated GHK is its sustained-release profile. Stability testing demonstrated that the conjugated form provides prolonged biological activity for up to 12 hours compared to 2-4 hours for standard free biotin applied topically. This extended duration reflects the slower hydrolysis of the biotin-peptide bond under physiological conditions and the stabilizing effect of the conjugation on the GHK component against peptidase degradation.

pH stability. The conjugated form demonstrates superior pH stability across the range typically encountered in topical formulations (pH 4.0-7.0), compared to free biotin which is more susceptible to degradation at acidic pH values. This stability advantage translates to better shelf life and consistent bioactivity in finished cosmetic products.

Systemic absorption. No studies have measured systemic bioavailability of biotinoyl tripeptide-1 following topical application. Given its molecular weight (567.68 Da, above the typical 500 Da cutoff for passive transdermal absorption) and the localized application to scalp or eyelashes, significant systemic absorption is unlikely. Systemic biotin levels sufficient to interfere with laboratory immunoassays (a known concern with oral biotin supplementation) are not expected from topical biotinoyl tripeptide-1 use [6].

Metabolism. At the follicular level, biotinoyl tripeptide-1 is likely hydrolyzed by local peptidases and esterases to release free biotin and the GHK tripeptide components, which then exert their respective biological activities on keratinocytes and dermal papilla cells. The GHK component may further complex with ambient copper ions in the skin to form GHK-Cu, potentially adding copper-delivery effects to the peptide's mechanism.

9. Dose-Response Relationships

The dose-response relationship for biotinoyl tripeptide-1 is primarily characterized by the ex vivo hair follicle growth data, which represent the most quantitative efficacy measurements available for this ingredient.

Ex vivo hair growth. Isolated cultured human hair follicles treated with biotinoyl tripeptide-1 demonstrated a clear dose-dependent response: growth increased by 58% at 2 ppm and 121% at 5 ppm compared to untreated controls. This 2.5-fold increase in concentration produced an approximately 2-fold increase in growth response, suggesting a steep dose-response curve in the biologically effective concentration range.

Ki-67 proliferation marker. The dose-dependent increase in Ki-67 expression (a marker of active cell division) in hair bulb keratinocytes corroborates the dose-dependent growth findings, confirming that higher concentrations of biotinoyl tripeptide-1 produce proportionally greater keratinocyte proliferation at the base of the hair follicle.

Formulation concentration. Cosmetic formulations typically contain 1-3% biotinoyl tripeptide-1. The ex vivo efficacy was demonstrated at 2-5 ppm (parts per million, equivalent to 0.0002-0.0005%), which is substantially lower than the concentrations used in commercial formulations. This suggests that commercial products provide biotinoyl tripeptide-1 at concentrations well above the minimum effective concentration, potentially accounting for incomplete penetration and delivery losses in real-world topical application.

Eyelash dose-response. In the mascara study, 2% biotinoyl tripeptide-1 produced 17% lash length increase and 19% lash thickness increase after 30 days. No dose-ranging was performed within the eyelash study, so the concentration-response for this specific application remains undefined.

Clinical hair lotion. The 6-month clinical study used a multi-ingredient formulation containing biotinoyl tripeptide-1, precluding determination of the individual dose-response contribution of the peptide. The 79% decrease in self-perceived hair loss and significant increases in total hair count and anagen hairs reflect the combined effect of all active ingredients.

10. Comparative Effectiveness

Biotinoyl Tripeptide-1 vs. Minoxidil

Minoxidil (2% and 5% topical solutions) is the most extensively studied topical hair loss treatment, with decades of clinical trial data and FDA approval for androgenetic alopecia [7][15]. Minoxidil promotes hair growth primarily through VEGF-mediated perifollicular vasodilation, potassium channel opening, and prolongation of the anagen growth phase [15]. In comparison, biotinoyl tripeptide-1 acts through keratinocyte proliferation and basement membrane protein synthesis -- a distinct and potentially complementary mechanism. No head-to-head clinical trials comparing these two agents exist. Minoxidil produces measurable hair regrowth in approximately 30-60% of users in clinical trials, with well-documented side effects including scalp irritation (occurring in 5-15%), initial shedding (telogen effluvium), and unwanted facial hair growth (hypertrichosis) [7][15]. Biotinoyl tripeptide-1 has not been associated with these side effects but lacks the rigorous clinical trial evidence supporting minoxidil.

Biotinoyl Tripeptide-1 vs. Finasteride (Topical/Oral)

Finasteride inhibits 5-alpha-reductase type II, reducing DHT-driven follicular miniaturization in androgenetic alopecia. Oral finasteride (1 mg/day) produces measurable hair regrowth in approximately 66-83% of men in pivotal trials but carries the risk of sexual side effects (decreased libido, erectile dysfunction in 1-5% of users) and mood changes. Biotinoyl tripeptide-1 does not target the androgen pathway and would not be expected to produce these side effects. The two agents have non-overlapping mechanisms and could theoretically be used in combination.

Biotinoyl Tripeptide-1 vs. GHK-Cu

As the parent compound, GHK-Cu shares the ECM-stimulating and wound healing properties of the GHK component in biotinoyl tripeptide-1 [2][3]. However, GHK-Cu has a broader evidence base for skin remodeling (multiple clinical trials) and lacks the biotin-mediated keratin support. For hair-specific applications, biotinoyl tripeptide-1 offers targeted follicular delivery through biotin conjugation and keratinocyte proliferation enhancement not documented for GHK-Cu alone. GHK-Cu's copper-binding capacity provides antioxidant and enzymatic support not present in biotinoyl tripeptide-1 (which lacks copper).

Biotinoyl Tripeptide-1 vs. Acetyl Tetrapeptide-3 (Capixyl)

Acetyl tetrapeptide-3, the peptide component of the commercial ingredient Capixyl, stimulates collagen III and laminin production in dermal papilla cells [12]. It also inhibits 5-alpha-reductase in vitro, potentially reducing DHT-mediated miniaturization. In a clinical study, the Capixyl formulation (containing acetyl tetrapeptide-3 plus red clover extract biochanin A) showed comparable efficacy to 3% minoxidil for hair density improvement [11]. Biotinoyl tripeptide-1 and acetyl tetrapeptide-3 have complementary mechanisms and are frequently combined in commercial hair care formulations.

| Feature | Biotinoyl Tripeptide-1 | Minoxidil (5%) | Finasteride (1mg) | Acetyl Tetrapeptide-3 | |---|---|---|---|---| | Evidence level | Preliminary | Strong (FDA-approved) | Strong (FDA-approved) | Preliminary-moderate | | Mechanism | Keratinocyte proliferation, laminin-5/collagen IV | VEGF, K+ channel, anagen prolongation | 5-alpha-reductase inhibition | Collagen III/laminin, anti-DHT | | Route | Topical | Topical | Oral (primarily) | Topical | | Side effects | Not reported | Scalp irritation, shedding, hypertrichosis | Sexual side effects (1-5%) | Not reported | | Monotherapy data | Ex vivo only | Extensive RCTs | Extensive RCTs | Limited RCTs | | Regulatory status | Cosmetic ingredient | FDA-approved drug | FDA-approved drug | Cosmetic ingredient |

11. Enhanced Safety Profile

Biotinoyl tripeptide-1 has an exceptionally favorable safety profile, consistent with its nature as a topical cosmeceutical peptide composed of two endogenous substances (biotin and GHK).

Clinical safety data. No serious adverse events have been reported in any published study involving biotinoyl tripeptide-1, including the 6-month clinical hair lotion study in 56 patients and the 30-day eyelash enhancement study. No contact sensitization, allergic reactions, or local irritation events have been documented in the published literature.

Periocular safety. Biotinoyl tripeptide-1 formulations are used in eyelash serums and mascaras applied to the periocular area, a region with thin, sensitive skin and proximity to the ocular surface. Available studies report good tolerability in this sensitive area, with no reports of ocular irritation, conjunctivitis, or iris color changes (the latter being a concern with prostaglandin analog lash serums such as bimatoprost).

Comparison with prostaglandin analogs for lash growth. Bimatoprost (Latisse, 0.03%) is the only FDA-approved treatment for hypotrichosis of the eyelashes and produces documented lash growth through prostamide receptor activation. However, bimatoprost carries risks of periorbital fat atrophy (giving a sunken eye appearance), iris darkening (permanent in some cases), conjunctival hyperemia, and periocular skin hyperpigmentation. Biotinoyl tripeptide-1 has not been associated with any of these adverse effects, offering a significantly better tolerability profile for cosmetic lash enhancement, albeit with a smaller evidence base.

Biotin laboratory interference. High-dose oral biotin supplementation (5-10 mg/day or higher) is known to interfere with streptavidin-biotin-based immunoassays, potentially causing falsely elevated or decreased results for troponin, thyroid function tests (TSH, free T4), and other analytes [6]. Topical biotinoyl tripeptide-1 at cosmetic concentrations is extremely unlikely to achieve systemic biotin levels sufficient to cause this interference. Nevertheless, patients undergoing laboratory testing should be aware of this general biotin consideration.

Pregnancy and lactation. No specific reproductive safety data exist for biotinoyl tripeptide-1. Both biotin and GHK are endogenous human molecules, and topical application at cosmetic concentrations is unlikely to pose meaningful systemic exposure. However, formal safety studies have not been conducted in these populations.

Environmental and regulatory safety. Biotinoyl tripeptide-1 has received favorable safety assessments from cosmetic ingredient review bodies, including the Environmental Working Group (EWG). It is listed in the INCI database and permitted in cosmetic formulations under both EU (EC Cosmetics Regulation 1223/2009) and US regulatory frameworks.

12. Related Peptides

See also: GHK-Cu, GHK, AHK-Cu, Acetyl Tetrapeptide-3

• GHK-Cu -- The copper-bound form of the parent GHK tripeptide. GHK-Cu has a broader evidence base for skin remodeling and wound healing, and its copper-binding capacity provides additional biological functions not present in biotinoyl tripeptide-1.

• GHK -- The free (copper-unbound) form of the parent tripeptide from which biotinoyl tripeptide-1 is derived. GHK modulates over 4,000 genes and has roles extending beyond hair care into tissue repair and disease gene expression.

• AHK-Cu -- A structurally related copper tripeptide (Ala-His-Lys-Cu) specifically engineered for hair growth through dermal papilla cell stimulation and VEGF induction. Complementary mechanism to biotinoyl tripeptide-1.

• Acetyl Tetrapeptide-3 -- Another hair-targeting biomimetic peptide (the peptide component of Capixyl) that stimulates collagen III and laminin production in dermal papilla cells. Often used alongside biotinoyl tripeptide-1 in hair care formulations.

13. References

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