Shop
Connect
Join our community
✔ Free U.S. Shipping - Ships within 24 hours
✔ 30 mL Premium Antioxidant Serum
✔ Science-Formulated Skincare
✔ Secure checkout
Ingredients (INCI): Aqua (Water), Ethoxydiglycol, Ascorbic Acid, Glycerin, Propylene Glycol, Laureth-23, Phenoxyethanol, Tocopherol, Triethanolamine, Ferulic Acid, Panthenol, Sodium Hyaluronate.
We will work quickly to ship your order as soon as possible. Once your order has shipped, you will receive an email with further information. Delivery times vary depending on your location.
1. What is C RADIANCE SERUM?
C RADIANCE SERUM is a high-potency antioxidant facial serum formulated with 15% L-ascorbic acid (Vitamin C), 1% Vitamin E, and 0.5% Ferulic Acid. It is designed to help visibly brighten skin, improve the appearance of uneven skin tone, and support skin against environmental stressors.
2. What skin concerns does it help address?
C RADIANCE SERUM is formulated to help improve the appearance of:
This product is a cosmetic and is not intended to diagnose, treat, cure, or prevent any disease.
3. How do I use it?
Morning use is recommended.
4. How often should I use it?
Begin every other morning for the first week.
If well tolerated, increase to once daily.
5. Can I use it at night?
Yes. While antioxidant protection is commonly used in the morning routine, it may also be applied at night if preferred.
6. How many drops should I apply?
Use enough to lightly cover the skin — typically 3 drops for the face, 4–5 if including neck. More product does not improve results and may increase irritation.
7. Should I wear sunscreen with this product?
Yes. Vitamin C is often used in daytime routines alongside sunscreen. Daily sun protection is
recommended regardless of skincare routine.
8. Why is this product important? What is the science?
The real structural change in collagen after age ~30:
Factor Change
Collagen production ↓ ~1% per year
Dermal thickness gradually decreases
Elastin fibers degrade and fragment
Glycosaminoglycans
(hydration molecules) decrease
Important nuance
The biggest collagen loss actually occurs at menopause, where studies show up to 30% loss in the first 5 years due to estrogen decline.
Why Vitamin C serums matter
Our C·E Ferulic–style
formula addresses two key mechanisms:
This is why this formulation category is widely studied in dermatology.
9. Is tingling normal?
A mild, brief tingling sensation may occur due to the acidic nature of pure L-ascorbic acid.
Discontinue use if you experience persistent irritation, burning, swelling, or
rash.
10. Should I patch test first?
Yes. Apply a small amount to a discreet area once daily for 24–48 hours before full use.
Individual skin responses vary.
11. Can I use this with retinol?
Yes. To minimize irritation:
Avoid layering multiple strong actives in the same routine if you are sensitive.
12. Can I use it with exfoliating acids (AHA/BHA)?
Use caution when combining strong actives. If irritation occurs, alternate days or separate into
morning and evening routines.
13. Can I use it with benzoyl peroxide?
To reduce potential interaction, use at different times of day (for example, Vitamin C in the morning and benzoyl peroxide at night).
14. Can I use it with niacinamide?
Yes. Most users tolerate the combination well. If you are sensitive, separate usage by time of day.
15. Is it safe for sensitive skin?
Many users with sensitive skin can tolerate it when introduced gradually. Start slowly and
monitor your skin’s response.
16. Can I use it around the eyes?
Avoid direct contact with eyes and lash line. Use cautiously on the orbital bone area if tolerated.
17. What color should the serum be?
At first opening, the serum may range from clear to light yellow or pale amber.
18. My serum has darkened slightly. Is that normal?
Vitamin C formulas may gradually deepen in color over time due to normal exposure to air and light
during use.
If the serum becomes very dark brown and develops a strong odor, replacement is recommended.
19. How should I store it?
20. How long does a bottle last?
With typical daily use (3–5 drops), one bottle generally lasts 4–5 months.
21. How long is it good after opening?
For best experience, we recommend using within 6 months after opening, as indicated by the Period After Opening (PAO) symbol on the packaging.
22. Does it have a scent?
Due to its active ingredients, the serum has a natural scent characteristic of Vitamin C and ferulic acid. No added fragrance is included.
23. Is it fragrance-free?
Yes. C RADIANCE SERUM does not contain added fragrance.
24. Is it cruelty-free?
ONECeuticals does not conduct animal testing on finished products. We work with suppliers who share our commitment to responsible practices.
25. Is it vegan?
Yes. C RADIANCE SERUM is formulated without any animal-derived ingredients or animal by-products. All components are plant-derived, synthetic, or produced through controlled fermentation processes.
In skincare, “vegan” means a product does not contain ingredients sourced from animals. It does not refer to ingestion.
26. Is it non-comedogenic?
The formula is lightweight and designed for broad skin compatibility. Individual responses vary.
27. What is the pH of the serum?
The formula is
maintained within an acidic range appropriate for L-ascorbic acid performance
(approximately pH 2.8–3.2).
28. Why is it packaged in amber glass?
Amber glass helps
reduce light exposure, supporting product stability.
29. Do you test each batch?
Yes. Each production
batch of C RADIANCE SERUM undergoes documented quality control verification
prior to release. This includes:
Only batches meeting
our internal quality criteria are approved for bottling and distribution.
30. Is it safe during pregnancy or breastfeeding?
Consult your healthcare provider if you are pregnant or breastfeeding before introducing new skincare products.
31. What if I experience irritation?
Discontinue use immediately and consult a healthcare professional if needed. If you have concerns about a defective product, contact support@oneceuticals.com within 14 days of delivery.
32. What is your return policy?
Due to hygiene and safety standards, opened or used products are not eligible for return.
We accept returns or issue refunds only if:
Requests must be submitted within 14 days of delivery.
33. How do I request a return?
Email support@oneceuticals.com with:
Do not return items
without prior authorization.
34. When will I receive my refund?
If approved:
If more than 15 business days have passed after approval, contact support@oneceuticals.com.
35. Are shipping fees refundable?
Shipping fees are non-refundable except in cases of error or confirmed defect.
36. Do you offer exchanges?
We do not offer direct exchanges. If eligible, request a refund and place a new order.
37. What about EU customers?
For merchandise shipped into the European Union, customers may cancel or return orders within 14 days, provided the item is unused, unopened, and in original packaging with proof of purchase.
Our products are manufactured in the USA.
A refined Vitamin C serum designed for daily use—balancing potency, ingredient transparency, and a luxurious skin feel.
Formulated with care. Designed with intention. Priced responsibly
Why This Formula Is Different
✔ Carefully curated Vitamin C
Features L-Ascorbic Acid at a 15% concentration, selected for its long history of use in cosmetic formulations. Formulated to support performance and stability.
✔ Supportive, thoughtfully chosen ingredients
We pair Vitamin C with Vitamin E, Ferulic Acid, a plant-derived antioxidant, and complementary humectants used to support stability and skin comfort.
✔ Stability-focused, low oxygen packaging
Nitrogen-blanketed filling in an amber bottle to help reduce oxygen and light exposure during filling.
✔ A luxury experience, without the markup
Lightweight texture, smooth application, and fast-absorbing feel—priced responsibly.
Many Vitamin C serums emphasize extremes—high percentages, heavy textures, or premium pricing—often at the expense of usability or ingredient transparency.
This formula was designed around a 15 : 1 : 0.5 ratio of key active components commonly used in advanced antioxidant serums and strikes a thoughtful balance between:
Because skincare should fit into real routines—not require compromise.
ONECeuticals blends the best of all worlds:
Scientific precision, natural purity and a luxury experience — all at a fair price.
Formulation-First Design
This serum features:
All bottled with reduced oxygen exposure to help support product integrity.
Crafted With Expertise
Scientifically formulated by a PhD chemist with a focus on:
Every component is chosen intentionally—because thoughtful formulation matters more than marketing buzzwords.
What We Leave Out—On Purpose
This formula is made without:
Instead, we focus on ingredients selected for their role in a well-balanced cosmetic formulation.
Designed for Everyday Use
Science-Minded Skincare, Made Accessible
Skincare shouldn’t feel exclusive or overwhelming.
At ONECeuticals, we believe in clear communication, intentional formulation, and pricing that reflects the product—not the hype.
This is skincare designed to support your routine, respect your skin, and fit real life.
Thoughtfully formulated. Purpose-driven. Accessible by design.