Product Overview

Ceramide AP (INCI: Ceramide AP, Ceramide 6 II, α-Hydroxy-N-stearoyl-phytosphingosine, CAS 212070-45-6, C₃₆H₇₁NO₅, MW ~600 g/mol) is a type IV ceramide under the Schoenmakers classification system — defined by a phytosphingosine (trihydroxy) backbone N-acylated with an α-hydroxy fatty acid (primarily α-hydroxystearic acid, C18:0). This classification is critical: among the 12+ ceramide subclasses in human stratum corneum, AP (type IV) is uniquely characterized by the combination of a trihydroxy long-chain base (phytosphingosine — three OH groups for tight headgroup hydrogen bonding) and an α-hydroxy fatty acid (an additional OH at the α-carbon of the fatty acid chain). This extra α-hydroxyl group is the structural basis for Ceramide AP’s functional distinction — it provides a fourth hydrogen-bond donor/acceptor site beyond the standard ceramide headgroup, enabling intermolecular cross-linking between adjacent ceramide molecules within the lamellar bilayer. The result is a tighter orthorhombic lipid packing with enhanced lateral cohesion — Ceramide AP essentially functions as a molecular “stitch” that cross-links neighboring ceramide molecules into a more unified, moisture-retentive barrier. Ceramide NP (type I, non-hydroxy fatty acid) provides the primary structural backbone of the lamellar bilayer, while Ceramide AP provides the polar hydrogen-bond cross-links that increase bilayer stability and water-holding capacity. This is why the Ceramide NP + AP + Cholesterol at a 3:1:1 molar ratio has become the gold-standard biomimetic formulation — replicating the physiological lipid composition of healthy stratum corneum and delivering 3-5× faster barrier recovery and statistically superior TEWL reduction versus single-ceramide or ceramide-free controls. Clinical studies demonstrate that formulations containing both NP and AP in the correct molar ratio reduce transepidermal water loss by 35-55% within 2-4 weeks, compared to 15-25% for NP-only formulations — the AP component contributing an additional ~20-30% TEWL reduction through its polar cross-linking mechanism. Ceramide AP is the second most abundant ceramide in human skin (~15-18% of total stratum corneum ceramides), and its relative depletion is a hallmark of barrier-compromised conditions including atopic dermatitis, aged/photoaged skin, and winter xerosis. UPOR Biotech provides synthetic (bioidentical) Ceramide AP in two grades: Cosmetic Grade (≥98% HPLC-ELSD) and Premium Grade (≥99% HPLC-ELSD), manufactured via phytosphingosine + α-hydroxy fatty acid amidation under cGMP conditions.

As a leading ceramide AP manufacturer and bulk supplier, UPOR Biotech provides high-purity Ceramide 6 II powder for B2B cosmetic brands, contract manufacturers, private-label formulators, and premium cosmeceutical companies worldwide. Ceramide AP’s unique α-hydroxy structure gives it a significant formulator advantage over non-hydroxy ceramides: the additional OH group enhances interfacial activity, improving emulsification properties in oil-in-water (O/W) systems — Ceramide AP disperses more readily and forms more stable lamellar emulsions compared to Ceramide NP, reducing the need for high-shear processing. This makes AP the preferred ceramide for formulators developing lightweight barrier repair milks, lotions, and fluid emulsions. OEM and private label formulations available with flexible MOQ starting at 1 kg. Free sample available for qualified buyers. Every shipment includes full documentation: COA, MSDS, HPLC-ELSD chromatogram, FTIR spectrum with α-OH confirmation, GC-FID fatty acid profile, and stability data. Position your brand at the forefront of clinically validated biomimetic barrier repair with UPOR Biotech’s Ceramide AP.

Ceramide AP vs Ceramide NP — The Polar Synergist: Why the α-Hydroxyl Group Makes Ceramide AP the Moisture-Retentive Cross-Linker of the Lamellar Bilayer

The skin barrier requires two complementary ceramide functions — structural backbone and polar cross-linking — and NP + AP deliver both. Ceramide NP (type I) uses a non-hydroxy fatty acid (no extra OH) to form the primary lamellar bilayer backbone; it provides the fundamental long-periodicity phase (LPP) structure but has limited hydrogen-bonding capacity beyond its phytosphingosine headgroup. Ceramide AP (type IV) adds a critical α-hydroxyl (-OH) group on the fatty acid chain — this extra OH serves as an additional hydrogen-bond donor/acceptor that forms intermolecular cross-links between adjacent ceramide molecules and interlamellar water molecules. The practical consequence: NP provides the bilayer scaffold, AP stitches it together. Formulations using NP alone achieve 15-25% TEWL reduction; adding AP at the correct 3:1 (NP:AP) molar ratio boosts TEWL reduction to 35-55% — a statistically significant ~20-30% improvement attributable specifically to AP’s polar cross-linking. Furthermore, the α-OH group enhances O/W emulsification — Ceramide AP disperses more readily into oil-in-water emulsions than non-hydroxy ceramides, reducing processing complexity and enabling lighter, more elegant textures. The combination is not additive — it is synergistic: the orthorhombic lateral packing enabled by AP’s hydrogen-bond cross-links cannot be achieved by NP alone, and the cohesive bilayer enabled by NP’s backbone structure cannot be achieved by AP alone. Ceramide NP + AP + Cholesterol (3:1:1 molar ratio) = the physiologically correct, clinically proven biomimetic barrier repair system.

Technical Specifications

PropertySpecification
Product NameCeramide AP (Ceramide 6 II) Powder — Cosmetic Grade (≥98%) / Premium Grade (≥99%)
INCI NameCeramide AP
Common Name / SynonymsCeramide 6 II; Ceramide AP; α-Hydroxy-N-stearoyl-phytosphingosine; N-(2-hydroxyoctadecanoyl)-phytosphingosine; Ceramide VI; Ceramide 6; α-Hydroxy-Ceramide
CAS Number212070-45-6
Molecular FormulaC₃₆H₇₁NO₅ (typical — α-hydroxystearic acid C18:0 + phytosphingosine C18)
Molecular Weight~600 g/mol (typical — varies with fatty acid chain length distribution)
Ceramide ClassificationType IV (Schoenmakers system) — phytosphingosine base + α-hydroxy fatty acid; also classified as Ceramide 6 II under the Wertz/Downing nomenclature
Chemical StructurePhytosphingosine (trihydroxy C18 long-chain base, D-ribo configuration) + N-linked α-hydroxy fatty acid (primarily α-hydroxystearic acid C18:0; also α-hydroxypalmitic C16:0 and trace α-hydroxyarachidic C20:0)
SourceSynthetic (bioidentical) — phytosphingosine + α-hydroxy fatty acid amidation under cGMP conditions. Structurally identical to endogenous human Ceramide AP.
Key Structural FeatureAdditional α-hydroxyl (-OH) group on the fatty acid α-carbon — provides an extra hydrogen-bond donor/acceptor site for intermolecular ceramide cross-linking and enhanced water binding within the lamellar bilayer
α-Hydroxy Fatty Acid Compositionα-Hydroxystearic acid (C18:0) ≥85%; α-Hydroxypalmitic acid (C16:0) ≤10%; α-Hydroxyarachidic acid (C20:0) ≤5%. Determined by GC-FID after acid methanolysis and derivatization.
Phytosphingosine Backbone Purity≥98% (HPLC-ELSD); D-ribo-phytosphingosine configuration confirmed by optical rotation and chiral HPLC; dihydrosphingosine and sphingosine impurities each ≤0.5%
AppearanceWhite to off-white crystalline powder; free-flowing, no visible aggregates or discoloration
Assay (Cosmetic Grade)≥98.0% (HPLC-ELSD, area normalization, C18 reverse-phase column, ELSD detection)
Assay (Premium Grade)≥99.0% (HPLC-ELSD, area normalization, C18 reverse-phase column, ELSD detection)
HPLC-ELSD MethodC18 reverse-phase column (250 × 4.6 mm, 5 μm); mobile phase: methanol/chloroform/water gradient; ELSD nebulizer 40°C, drift tube 80°C, N₂ gas 2.5 L/min; injection volume 20 μL
FTIR SpectrumBroad O-H stretching absorption at ~3450 cm⁻¹ — characteristic of the additional α-hydroxyl group (distinguishes AP from non-hydroxy ceramides NP/NS which lack this band). Amide I (C=O stretch) at ~1645 cm⁻¹; Amide II (N-H bend) at ~1550 cm⁻¹; C-H stretching (CH₂ asymmetric/symmetric) at ~2920 cm⁻¹ and ~2850 cm⁻¹.
Melting Point75–85°C (typically lower than Ceramide NP at ~93-98°C — the α-OH group disrupts tight crystalline packing, lowering the melting transition and improving processing characteristics)
Solubility / DispersibilityLipophilic — soluble in hot ethanol, chloroform, and chloroform/methanol mixtures (2:1 v/v); dispersible in hot oil phase (70-80°C) for emulsion incorporation. Practically insoluble in water.
Heavy Metals (Total)≤10 ppm (as Pb)
Elemental ImpuritiesPb ≤2 ppm; As ≤1 ppm; Hg ≤1 ppm; Cd ≤1 ppm; Ni ≤5 ppm (USP <232> / ICH Q3D compliant)
Microbial LimitsTAMC ≤100 CFU/g; TYMC ≤10 CFU/g (USP <61> / EP <2.6.12>); Pathogens (E. coli, Salmonella, S. aureus, P. aeruginosa) — Absent in 10 g (USP <62> / EP <2.6.13>)
Residual SolventsUSP <467> / ICH Q3C Class 3 compliant; methanol ≤3000 ppm, chloroform ≤60 ppm, ethanol ≤5000 ppm
Recommended Usage Rate0.1–1.0% in leave-on formulations; 0.3–0.5% most common for barrier repair. Must be formulated within a physiological lipid system (NP + Cholesterol + free fatty acids) for proper lamellar incorporation.
Optimal Formulation Molar RatioCeramide NP : Ceramide AP : Cholesterol = 3:1:1 (weight ratio approximately 3:1:1). Free fatty acids (palmitic/stearic/oleic) recommended at 1-2× the total ceramide weight for complete bilayer formation.
Grade / StandardsCosmetic Grade (≥98% HPLC-ELSD) / Premium Grade (≥99% HPLC-ELSD). COSMOS-compliant for natural and organic cosmetic formulations.
CertificationsISO 9001:2015, ISO 22000, HACCP, FDA Facility Registration, HALAL, KOSHER, Non-GMO, BSE/TSE-Free, COSMOS-compliant
Packaging1 kg / 5 kg / 10 kg sealed aluminum foil bags with PE liner under nitrogen blanket; 25 kg fiber drums with double PE liner. Oxygen absorbers included for oxidative stability.
Storage2–8°C, tightly sealed in original container under inert gas, protect from light, moisture, and oxygen. Ceramide AP is susceptible to oxidative degradation of the α-hydroxy fatty acid — proper cold-chain storage is essential for long-term stability.
Shelf Life2 years from date of manufacture under recommended refrigerated storage conditions (2–8°C)

Key Benefits — Ceramide AP

α-Hydroxy Polar Cross-Linking for Stronger Lamellar Bilayer Cohesion

The additional α-hydroxyl (-OH) group on Ceramide AP’s fatty acid chain provides extra hydrogen-bond donor/acceptor sites — enabling intermolecular cross-links between adjacent ceramide molecules and interlamellar water. This creates tighter orthorhombic lipid packing and superior moisture retention vs non-hydroxy ceramides.

α-OH Cross-Linking

NP+AP+Cholesterol 3:1:1 — Clinically Proven Gold Standard for Barrier Repair

The Ceramide NP + AP + Cholesterol 3:1:1 molar ratio replicates physiological stratum corneum lipid composition — delivering 3-5× faster barrier recovery and 35-55% TEWL reduction versus 15-25% for NP-only formulations. The AP component contributes an additional ~20-30% TEWL reduction through polar cross-linking.

35-55% TEWL Reduction

Enhanced O/W Emulsification — Formulator-Friendly α-Hydroxy Advantage

The α-OH group increases Ceramide AP’s interfacial activity, improving dispersibility and emulsification in oil-in-water systems compared to non-hydroxy ceramides like NP. Enables lighter, more elegant barrier repair textures — lotions, milks, and fluid emulsions — with reduced high-shear processing requirements.

O/W Formulation Edge

Second Most Abundant Skin Ceramide — Bioidentical to Human Stratum Corneum

Ceramide AP constitutes ~15-18% of total stratum corneum ceramides in healthy human skin. Its relative depletion is a hallmark of atopic dermatitis, aged skin, and barrier-compromised conditions. UPOR’s synthetic bioidentical AP restores physiological ceramide ratios without animal-derived ingredients.

COSMOS-Compliant Bioidentical

Applications

Barrier Repair Creams & Intensive Moisturizers

Ceramide AP at 0.3-0.5% with NP + Cholesterol (3:1:1) in rich barrier repair creams for atopic dermatitis, winter xerosis, and chronically compromised skin. The gold-standard biomimetic lipid system for clinically validated TEWL reduction. OEM and private label formulations available with flexible MOQ starting at 1 kg.

Anti-Aging & Skin Restructuring Serums

Ceramide AP at 0.2-0.5% in anti-aging serums targeting age-related ceramide depletion. Combined with niacinamide (upregulates endogenous ceramide synthesis) for comprehensive barrier restoration in mature and photoaged skin.

Atopic Dermatitis & Sensitive Skin Therapeutics

Ceramide AP at 0.3-0.5% in therapeutic emollients for atopic dermatitis — NP:AP:Chol 3:1:1 ratio restores the pathologically depleted ceramide profile and reduces flare frequency. Compatible with colloidal oatmeal, panthenol, and anti-inflammatory actives.

After-Sun & Post-Procedure Barrier Recovery

Ceramide AP at 0.3-0.5% in after-sun and post-peel/laser recovery formulations. The α-OH group’s enhanced water-binding capacity accelerates rehydration and barrier restoration after UV exposure and cosmetic procedures.

Premium Cosmeceutical Lamellar Emulsions

Ceramide AP at 0.3-0.5% in liquid-crystalline lamellar emulsions that mimic the skin’s natural bilayer structure. The α-OH group enables lighter O/W textures while maintaining physiological lipid organization — ideal for premium cosmeceutical brands.

Baby & Infant Skin Barrier Protection

Ceramide AP at 0.1-0.3% in baby creams, diaper balms, and infant moisturizers. COSMOS-compliant, bioidentical, and non-irritating — safe for the most delicate skin. Restores the immature infant skin barrier’s ceramide profile to adult-equivalent function.

Frequently Asked Questions

Ceramide AP (Ceramide 6 II, CAS 212070-45-6, INCI: Ceramide AP) is a type IV ceramide defined by a phytosphingosine backbone N-acylated with an α-hydroxy fatty acid (primarily α-hydroxystearic acid C18:0). It is the second most abundant ceramide in human stratum corneum (~15-18%). The defining structural feature is the additional α-hydroxyl (-OH) group on the fatty acid α-carbon — this provides an extra hydrogen-bond donor/acceptor site beyond the standard ceramide headgroup. This extra OH enables intermolecular hydrogen-bond cross-linking between adjacent ceramide molecules within the lamellar bilayer, creating tighter orthorhombic lateral lipid packing and a more cohesive, moisture-retentive barrier. Ceramide AP is often described as the “polar cross-linker” — while Ceramide NP provides the structural backbone, AP stitches neighboring ceramides together laterally through its additional H-bonding capacity, significantly increasing barrier stability and water-holding capacity. UPOR Biotech provides synthetic bioidentical Ceramide AP in two grades: cosmetic (≥98% HPLC-ELSD) and premium (≥99% HPLC-ELSD).

Ceramide NP and Ceramide AP work synergistically, not additively — they provide complementary functions essential for a complete, functional skin barrier. Ceramide NP (type I, non-hydroxy fatty acid, ~22-25% of SC ceramides) provides the primary lamellar bilayer backbone and establishes the long-periodicity phase (LPP) — the fundamental repeating lipid structure of the stratum corneum barrier. Ceramide AP (type IV, α-hydroxy fatty acid, ~15-18% of SC ceramides) provides polar hydrogen-bond cross-linking between adjacent ceramide molecules, increasing lateral cohesion and water-holding capacity within the bilayer. Clinically, formulations containing NP alone achieve 15-25% TEWL reduction; adding AP at the correct 3:1 (NP:AP) molar ratio boosts TEWL reduction to 35-55% — an additional ~20-30% improvement attributable to AP’s polar cross-linking. The Ceramide NP + AP + Cholesterol 3:1:1 molar ratio is the gold-standard biomimetic formulation — replicating physiological SC lipid composition and delivering 3-5× faster barrier recovery than untreated skin. This combination is particularly effective for atopic dermatitis, aged/photoaged skin, and winter xerosis — conditions where both total ceramide levels and the NP:AP ratio are pathologically depleted.

Recommended usage rate: 0.1–1.0% in leave-on formulations. 0.3–0.5% is the most common and clinically validated concentration for barrier repair. Ceramide AP must be formulated within a physiological lipid system for proper lamellar incorporation — ceramides alone cannot form functional bilayers. The gold-standard molar ratio is Ceramide NP : Ceramide AP : Cholesterol = 3:1:1 (approximate weight ratio 3:1:1). Free fatty acids (palmitic, stearic, oleic) at 1-2× total ceramide weight are essential co-lipids. Ceramide AP is lipophilic — pre-dissolve in the oil phase at 70–80°C with cholesterol and fatty acids before emulsification. The α-OH group enhances O/W emulsification compared to non-hydroxy ceramides, enabling lighter textures with less high-shear processing. For optimal lamellar structuring, use a high-pressure homogenizer or microfluidizer during cooling. Compatible with: cholesterol, free fatty acids (C16:0-C18:1), phytosterols, ceramide NP, ceramide EOP, niacinamide (synergistic — upregulates endogenous ceramide synthesis), panthenol, and glycerin. Avoid >20% non-polar emollients (mineral oil, dimethicone above 5%) which can disrupt lamellar packing. Always pair with a broad-spectrum preservative system — the lipid-rich environment supports microbial growth if not adequately preserved.

Human stratum corneum contains 12+ ceramide subclasses (types I-VIII, Schoenmakers system), each with distinct sphingoid base + fatty acid combinations and unique barrier functions. Ceramide NP (type I, Ceramide 3): phytosphingosine + non-hydroxy fatty acid — most abundant (~22-25%), primary lamellar backbone, essential for LPP structure. Ceramide AP (type IV, Ceramide 6 II): phytosphingosine + α-hydroxy fatty acid — second most abundant (~15-18%), polar cross-linker, moisture retention, enhanced O/W emulsification. Ceramide EOP (type VI, Ceramide 1): phytosphingosine + ω-esterified ω-hydroxy ultra-long-chain fatty acid (C28-C36) — “molecular rivet” spanning adjacent lamellae, critical for long-periodicity phase and corneocyte lipid envelope attachment. Ceramide NS (type II, Ceramide 2): sphingosine (dihydroxy) + non-hydroxy fatty acid — baseline bilayer structure, less H-bonding capacity than phytosphingosine-based ceramides. Ceramide AS (type V, Ceramide 5): sphingosine + α-hydroxy fatty acid — polar cross-linking with dihydroxy base (lower H-bonding than AP’s trihydroxy base). Ceramide AP is unique because it combines three optimal features: (1) trihydroxy phytosphingosine base for maximum headgroup H-bonding, (2) α-hydroxy fatty acid for lateral polar cross-linking, and (3) intermediate C18 chain length for optimal bilayer integration. For the most comprehensive barrier repair, the combination NP + AP + EOP + Cholesterol = 3:1:0.5:1 molar ratio provides all three ceramide functional classes simultaneously.

Every shipment includes: COA (HPLC-ELSD purity ≥98.0% cosmetic or ≥99.0% premium, α-hydroxy fatty acid composition by GC-FID, phytosphingosine backbone purity ≥98%, full impurity profile, heavy metals ≤10 ppm with Pb ≤2 ppm / As ≤1 ppm / Hg ≤1 ppm / Cd ≤1 ppm, residual solvents per USP <467> / ICH Q3C, microbial panel per USP <61>/<62> and EP <2.6.12>/<2.6.13>), MSDS, HPLC-ELSD Chromatogram (signed and dated, C18 reverse-phase with ELSD detection), FTIR Spectrum (confirmation of α-OH stretch at ~3450 cm⁻¹, Amide I ~1645 cm⁻¹, Amide II ~1550 cm⁻¹), GC-FID Fatty Acid Profile (α-hydroxystearic C18:0 ≥85%), COSMOS Compliance Certificate, BSE/TSE-Free Statement, Non-GMO Statement, Allergen Statement, HALAL Certificate, KOSHER Certificate, ISO 22000 + HACCP, ISO 9001:2015, FDA Facility Registration, Stability Data (2-8°C real-time 24-month and 40°C/75%RH accelerated 6-month), and Complete Lot Traceability from raw material to finished product. Free sample available for qualified B2B buyers. MOQ: 1 kg. All documents provided in English.