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The skin will tell you the rest.

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Defense Serum
DefendAM / PMBarrier + Detox
$75.00
Tube of INBAR + CO defense serum on a white background
Sensitivity + Barrier Protection

DefenseSerum

A daily protect-and-detox serum for skin carrying the load of modern exposure. Activates the skin's own detox enzymes, neutralizes oxidative stress, supports hydration, and strengthens resilience before the seal.

Sensitive + ReactiveBarrier RepairEnvironmental Shield
$75.00 30 ml / 1 fl oz
100% PLASTIC-FREE
Formulated & shipped from Resonance Marin, Marin County, CA
Returns accepted within 30 days — half-full minimum
24h
Barrier reinforcement reduces trans-epidermal water loss within 24 hours.
85%
Of visible skin changes trace to environmental exposure.
72h
Moisture reservoir that binds to skin cells and holds deep hydration for up to 72 hours.
100%
Plastic-free aluminum packaging, fully recyclable.
The Brief

Defend from the inside out.
Protection from the outside in.

Developed alongside Recovery Cream for skin that is working harder than it should have to. A stressed barrier becomes a sensitive skin: more reactive, more dehydrated, more visible in its distress. Defense Serum addresses that from both directions. It activates the skin's own repair and detox mechanisms while shielding against the environmental exposure that depletes the barrier fastest.

Read more

Plant extracts activate the enzymes that clear oxidative buildup and defend against pollution, switching on internal defenses rather than adding another layer on top. A collagen-mimicking peptide drives one of the skin's most powerful antioxidant mechanisms, neutralizing free radicals from pollution, UV, and blue light. A freshwater microalgae extract adds a targeted shield against screen and sun exposure. Four weights of hyaluronic acid rebuild moisture at every depth simultaneously.

Result: with consistent use, skin appears smoother, more resilient, and visibly clearer. Less reactive, better hydrated, and more stable in the face of daily environmental stress.

The Brief
Where it fits
Where
it fits.
Morning
or evening.

Defense Serum is the protect and detox layer. Apply after hydration and before Recovery Cream. It reduces the stress load before the barrier is sealed.

01
Cleanse
Gentle Cleanser
Cleanses without stripping.

Apply to damp skin and massage lightly. Rinse with lukewarm water. A barrier-safe cleanse keeps the surface intact before defense.

02
Activate
XO Essence
Calms, hydrates, and prepares skin.

Apply to damp skin after cleansing. XO Essence calms and prepares the skin before the water layer.

03
Hydrate
Hydrate Serum
Adds water before defense.

Apply while skin is still damp. Hydrate Serum adds water-binding hydration before the protect and detox layer.

04
Defend
Defense Serum
Protects, detoxes, and reduces stress load.
You are here

Apply after hydration. Defense Serum activates the skin's own detox enzymes, neutralizes oxidative stress, and reduces the daily exposure load before the barrier is sealed.

05
Seal
Recovery Cream
Repairs the barrier and locks support in.

Apply after Defense Serum. Recovery Cream repairs the barrier and seals every layer beneath it in place.

06
Protect
Shield SPF 35+
Protects from daily UV stress.

Apply every morning as the final daytime step. UV exposure compromises barrier function and increases the daily stress load Defense Serum is built to address.

Build Around This Step
Choose the next level of commitment: one product, a pair, a starter trio, or the full system.
Recovery Cream Seal
Repair + Seal
Recovery Cream

The repair and seal after Defense Serum.

Barrier System Complete
Barrier System
Barrier System

The complete barrier sequence: cleanse, activate, hydrate, defend, seal, and protect.

2015
One of the most important serums in the line. It detoxes and protects in the same pass. Offense and defense, in one step. Antioxidants are quiet work. They do not give you the dramatic before-and-after a TikTok needs. What they do is keep the rest of the routine from undoing itself by Tuesday.
— Daniella Inbar, Founder
The Science

Your skin has detox enzymes. This formula turns them on. Clear from the inside out.

01
Eggplant + Broccoli / Phase II Detox Activation
Solanum Melongena (Eggplant) Fruit Extract and Brassica Oleracea Italica (Broccoli) Extract activate the enzymes already present in the skin to clear oxidative buildup and defend against pollution. Most antioxidants add a protective layer on top. This one switches on the skin's own detox process from within. Improves pore clarity and helps balance sebum as the barrier recovers.
02
Copper Tripeptide-1 / Radical Scavenger Complex
A collagen-mimicking tripeptide that activates superoxide dismutase, one of the skin's most powerful built-in antioxidant responses. Neutralizes free radicals from pollution, UV, and infrared while supporting the collagen matrix. Helps even out dullness and discoloration caused by cumulative environmental exposure.
03
Scenedesmus Rubescens / Green Freshwater Microalgae
A green freshwater microalgae extract that shields the skin against UV and blue light while actively supporting radiance and evening out discolorations. Delivers environmental defense and brightening in the same step. Particularly effective for the cumulative dullness that screen exposure and urban light create over time.
04
4-Weight Hyaluronic Acid / Layered Hydration
Four molecular weights of hyaluronic acid that hydrate the skin simultaneously at surface, mid-layer, and deep reservoir level. Saccharide Isomerate binds to skin cells directly and holds that moisture for up to 72 hours, the reason the hydration from this formula outlasts the routine. A barrier that stays hydrated tolerates stress, products, and environmental exposure far better.
From the Treatment Room

Tips
from the spa.

Born in the spa, Defense Serum reflects practitioner insight: the barrier is not just a boundary, it is a living system that repairs, detoxes, and rebuilds when given the right support. In the treatment room, we use it alongside Recovery Cream for clients whose skin is reactive, sensitized, or recovering from procedure stress. At home, it gives the barrier what it needs to stay stable: daily repair, daily detox, and a shield against the conditions that erode it fastest.

Barrier Reset Ritual
After outdoor time, urban errands, or travel, apply Defense Serum to clean skin to help neutralize oxidative buildup and reinforce barrier recovery. For a deeper reset, layer with Radiance Mask first, leave on until dry, then cleanse with warm water. Apply Defense Serum again and finish with a generous layer of Recovery Cream. This is the same sequence used in the treatment room for clients whose barrier has been under sustained stress.
Sensitive Skin Layering
For reactive or barrier-compromised skin, apply Defense Serum as the final serum step morning and evening. In the morning, follow with Shield Primer and SPF for complete environmental protection. At night, layer Recovery Cream over Defense Serum to create the dual repair stack: Phosphatidylcholine and Ectoin underneath, Tazman Pepper and ceramides on top. This overnight combination addresses barrier stress from both a lipid-repair and an anti-inflammatory angle.
Travel Fortification
Use during flights to counteract the dehydrating effects of recycled cabin air. Layer Hydrate Serum first, follow with Defense Serum for environmental protection, then seal everything in with Recovery Cream. The ceramide complex helps maintain moisture and keeps reactive skin stable through long travel days.
Cellular Renewal Ritual
A spa-inspired rejuvenation stack for restored vitality and amplified glow. Cleanse to prep and soften skin. Apply XO Essence to hydrate and enhance absorption. Apply XO Bloom Serum for advanced cellular communication and renewal. Layer Defense Serum to detox, repair the barrier, and support environmental resilience. Seal in with Protect Oil for a smooth, radiant, revived complexion.
The Details

Every question,
answered.

Formulated at Resonance Marin. Tested on real skin. These are the questions that matter most.

Where does Defense Serum fit in the system?
Defense Serum sits after hydration and before Recovery Cream. It protects and detoxes so the barrier is under less stress before it is sealed.
Is Defense Serum suitable for sensitive skin?
Yes. The formula is featherlight and designed to support barrier function, making it suitable for sensitive, reactive, and dehydrated skin types. A plant extract complex activates the skin's own detox enzymes without irritating it, and four weights of hyaluronic acid rebuild hydration gently and deeply, both are exceptionally well tolerated by compromised or reactive skin.
Can I use Defense Serum with retinol or exfoliating acids?
Yes. Use Defense Serum after retinoids or acids at night to reinforce the barrier and support recovery. The plant detox complex and collagen peptide specifically counteract oxidative stress and barrier disruption that retinoids and acids can create. It is the same logic as pairing it with Recovery Cream.
What does a pollution-protection serum do for the skin?
Pollution-protection serums help shield the skin from particulate matter, blue light, and environmental stressors that contribute to dullness, uneven tone, and premature aging. Defense Serum activates the skin's own detox enzymes via a plant extract complex, shields against UV and blue light with green microalgae, and neutralizes free radicals with a collagen peptide antioxidant complex. Addressing environmental damage at the cellular level rather than just coating the surface.
Does blue light really affect the skin?
Yes. Research shows HEV (blue light) can generate oxidative stress similar to UV exposure. Defense Serum includes a green microalgae extract studied for UV and blue light protection alongside a peptide radical scavenger complex to help counteract this impact.
Can I use Defense Serum under sunscreen?
Absolutely. Layering barrier-supportive actives and antioxidants beneath SPF creates a more comprehensive defense. The SPF blocks UV, while Ectoin and Green Tea address the pollution, blue light, and infrared that SPF alone does not cover.
How long until I see results?
Immediate comfort and smoothness can be expected, with visible clarity, improved tone, and strengthened resilience developing over 2 to 4 weeks of consistent daily use.
Formula Feel
Light enough for sensitive skin. Heavy enough to matter.

The aroma is a quietly elegant, nature-inspired blend replicating the distinct scent of Marin County's coastal air and forests, the environment this formula was made in, and made to support.

Cypress + SpruceTop
Lavender + FirHeart
Meyer Lemon BlossomHeart
Featherlight Satin FinishTexture
Full Ingredient List
Every ingredient, listed.
Aqua, Glycerin, Polyglycerin-6, Propanediol, Solanum Melongena (Eggplant) Fruit Extract, Bioflavonoids, Brassica Oleracea Italica (Broccoli) Extract, Panthenol, Glycine, Mannitol, Tromethamine, Glutamic Acid, Arginine HCl, Alanine, Aspartic Acid, Lysine HCl, Leucine, Valine, Citric Acid, Isopropyl Alcohol, Sodium Lactate, Sorbitol, Glucose, Phenylalanine, Isoleucine, Tyrosine, Histidine HCl, Hydrolyzed Soy Protein, Copper Tripeptide-1, Sodium Hyaluronate Crosspolymer, Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydrolyzed Sodium Hyaluronate, Pentylene Glycol, Cyclopentasiloxane, Dimethicone, Xanthan Gum, Allantoin, Aloe Barbadensis Leaf Juice, Sodium Phytate, Sodium Acrylates Copolymer, Lecithin, Sclerotium Gum, Pullulan, Polysilicone-11, Butylene Glycol, Decyl Glucoside, Polymethylsilsesquioxane/Silica Crosspolymer, Xylitylglucoside, Anhydroxylitol, Xylitol, Saccharide Isomerate, Sodium Citrate, Scenedesmus Rubescens Extract, Tocopheryl Acetate, D-Panthenol, Synthetic Fluorphlogopite, Titanium Dioxide, Tin Oxide, Phenoxyethanol, Ethylhexylglycerin, Parfum, Limonene, Linalool

Defend the barrier daily.

Defense Serum activates the skin's own detox enzymes, neutralizes oxidative stress, and reinforces the barrier before the seal. A daily protect-and-detox layer for skin under modern exposure load.

$75.00Defense Serum
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