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View compareC15 CelSignal MAP Serum
C15 CelSignal MAP Serum
Our Price
$29.99 USD
Actual Price
Our Price
$29.99 USD
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per
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★★★★★
4.6
5 reviews
Gentle vitamin C at pH 5.5, for skin that stings with L-ascorbic acid.
- Magnesium ascorbyl phosphate converts to vitamin C in the skin
- Skin-friendly pH 5.5, formulated to be tingle-free
- Brightens and supports an even-looking tone, gently
- Fragrance-free and oil-free
15% Magnesium Ascorbyl Phosphate1 fl oz (30 ml)pH 5.5Reactive, easily irritated skin
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If a NuFountain serum isn't right for you, contact us within 30 days of delivery and we'll refund you in full. You don't need to return the bottle.
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Vitamin C for skin that can't handle L-ascorbic acid. Built on 15% magnesium ascorbyl phosphate (MAP) — a mild vitamin C that converts in the skin — at a comfortable pH 5.5, with niacinamide and hyaluronic acid.
- No sting: MAP is a gentle vitamin C at skin-friendly pH 5.5
- Made for sensitive, reactive and acne-prone skin
- Niacinamide + hyaluronic acid for even tone and hydration
- A vitamin C option when traditional serums are too much
Freshly made, gently formulatedBlended the day it ships and hand-dated — the same fresh-made care as our L-ascorbic serums, in a formula built for reactive skin.
Blended fresh to order
Hand-dated bottle
Made in the USA
0★ from 5 reviews
The NuFountain difference
Vitamin C without the tingle
Traditional L-ascorbic acid is powerful, but its low pH and strength can be too much for reactive skin. MAP (magnesium ascorbyl phosphate) is a gentler, more stable vitamin C that converts to active vitamin C in the skin — so you get the benefits at a comfortable pH 5.5, without the burn.
Typical shelf serum
- Mixed weeks or months before you buy it
- No way to know how old the vitamin C really is
- Potency quietly drops as it oxidizes
- Often padded with fillers and fragrance
NuFountain C15 CelSignal MAP
- Blended the day your order ships
- Hand-dated so you see exactly how fresh it is
- Gentle MAP vitamin C at a comfortable pH 5.5
- Short, transparent ingredient list — nothing you don't need
What it does
Kind to skin that reacts to everything
A calmer route to vitamin C's brightening and antioxidant benefits, with support from niacinamide and hyaluronic acid.
No-sting vitamin C
MAP delivers vitamin C benefits at pH 5.5, so even reactive, easily-irritated skin can use it comfortably.
Evens & calms tone
Niacinamide helps fade discoloration and soothe redness for a more balanced, even complexion.
Hydrates & supports
Hyaluronic acid and pro-vitamin B5 keep skin cushioned, hydrated and comfortable.
What's inside
Gentle actives, thoughtfully layered
A calming, hydrating vitamin C formula built around a mild, stable form of the vitamin.
15%
Magnesium Ascorbyl Phosphate (MAP)
A gentle, stable vitamin C derivative that converts to active vitamin C in the skin — brightening without the low-pH sting.
+
Niacinamide
Helps even tone, calm redness and reinforce the skin barrier.
+
Hyaluronic Acid
Draws in moisture for hydrated, cushioned skin.
+
Panthenol (Pro-Vitamin B5)
Soothes and conditions for lasting comfort.
Full ingredient list
Purified Water, Magnesium Ascorbyl Phosphate, Niacinamide, DL-Panthenol, Sodium Hyaluronate, Hydrolyzed Oats, Nannochloropsis Oculata, Pullulan, Glycerin, Citric Acid.
What to expect
Real results run on consistency
Gentler actives work gradually. Here's an honest timeline — results vary, and daily sunscreen protects your progress.
Weeks 1–2
Calm & comfortable
Skin gets used to it easily — no stinging — and often looks a little more hydrated and calm.
Weeks 4–6
More even tone
Redness settles and tone begins to look more balanced with daily use.
Weeks 8–12
Brighter, healthier
Consistent use brings a clearer, brighter, more resilient-looking complexion.
How to use
Four gentle steps
1
Cleanse
Start with clean, dry skin.
2
Apply 5–6 drops
Pat gently over the face and neck. No tingle — it's designed to be comfortable.
3
Let it absorb
Give it a minute to dry before your next step.
4
Moisturize + SPF
Follow with moisturizer, and always sunscreen in the morning.
Made for reactive skin. You can generally use C15 MAP daily. It layers well with other gentle actives. Store cool and dark and refrigerate unopened bottles to keep it fresh. If you want a stronger dose later and your skin can tolerate it, try our L-ascorbic C10 or C20.
Protect your results
Vitamin C works best with daily sunscreen
We don't sell sunscreen — so this isn't an upsell. It's the single most important thing you can do to protect what your serum is working toward, and it's worth getting right.
Without daily SPF
- UV light breaks vitamin C down and undoes your brightening
- New dark spots and sun damage keep forming
- Collagen breakdown speeds up, so fine lines deepen
- Your serum is left fighting an uphill battle
Vitamin C + daily SPF
- Locks in and protects your brightening progress
- Helps stop new dark spots before they start
- Guards the collagen your serum is helping build
- The two work together for visibly better results
What to look for in a sunscreen
Broad-spectrum
Look for the words “broad-spectrum” — it protects against both UVA (aging) and UVB (burning) rays.
SPF 30 or higher
SPF 30 blocks about 97% of UVB. Go higher if you're outdoors a lot — just don't drop below 30.
Every single morning
Apply as the last step of your morning routine, over your serum. Reapply every two hours in direct sun.
A texture you'll wear
Mineral (zinc oxide, titanium dioxide) or a modern chemical filter — pick one that feels good so you use it daily.
Reviews
For skin that says no to everything else
0
☆☆☆☆☆
5 verified reviewsGood to know
Questions, answered
What is MAP and how is it different from L-ascorbic acid?
MAP (magnesium ascorbyl phosphate) is a gentle, stable form of vitamin C that converts to active vitamin C in your skin. It works at a comfortable pH 5.5 instead of the low pH of L-ascorbic acid, so it delivers vitamin C benefits without the tingle — ideal for sensitive skin.
Who should choose C15 MAP over the L-ascorbic serums?
Choose C15 MAP if L-ascorbic acid serums sting, if you have rosacea, sensitive or easily-irritated skin, or if you simply prefer a no-tingle vitamin C. If your skin tolerates stronger actives, our C10 or C20 offer a higher-strength L-ascorbic dose.
Will it still brighten if it's so gentle?
Yes — MAP is a well-studied vitamin C derivative that supports brightening and antioxidant defense. It simply works more gradually and gently than high-strength L-ascorbic acid.
How should I store it?
Keep the cap closed and store in a cool, dark place; refrigerate unopened bottles. MAP is more stable than L-ascorbic acid, but fresh is still best — use opened bottles within a few months.
What if it doesn't work for me?
You're covered by our 30-day money-back guarantee — no need to return the bottle. If you're not happy, contact us for a full refund.
Zero risk
Try it for real. If it's not for you, we'll refund you.
We stand behind every fresh-blended bottle with a 30-day money-back guarantee — no returns required. That's how confident we are in what "fresh" does for your skin.
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