Non-crosslinked HA (Non-crosslinked hyaluronic acid)
This document is technical information about materials. It does not recommend any procedure or product.
In brief
Hyaluronic acid injected without being chemically linked into a network. It does not hold shape and is cleared far sooner than the crosslinked form, so the literature discusses it under skin quality and hydration rather than volume. This is the material behind most products described as skin boosters or bio-revitalisers.
Regulatory identity by market
COS cosmetic · MD medical device · RX drug · — not established in public sources
Identity & physical properties
| Synonyms | Non-crosslinked hyaluronic acid, Non-crosslinked HA, Uncrosslinked HA, Skin booster HA, Bio-revitalisation HA |
|---|---|
| Formula | (C14H21NO11)n |
| Family | ECM component — polysaccharide |
| Morphology | Injectable solution rather than a gel. Delivered intradermally in small aliquots across an area rather than shaped in one place |
| Molecular weight | Reported preparations span high and low molecular weight, and review literature describes hybrid complexes combining the two |
Mechanism
This material supplies matrix rather than provoking the host to build it. Hyaluronan is native to the dermal extracellular matrix and binds water. Without crosslinking there is no network to resist enzymatic clearance, so the reported mechanism is hydration and matrix supply over a shorter window rather than structural support.
Evidence
| PMID | Study type | Summary |
|---|---|---|
| 37577796 | RCT | Randomised multicentre controlled trial of an injectable hyaluronic acid solution for superficial wrinkles and skin quality on face, neck and decolletage |
| 36098653 | review | Review of hyaluronic acid mesotherapy for facial rejuvenation, covering longevity, adverse effects and injection technique |
| 38542191 | review | Review of intradermal hybrid complexes combining high- and low-molecular-weight hyaluronan |
Regulatory identity — detail
| Market | Classification | Note | Basis |
|---|---|---|---|
| KR | unclassified | Not established from public sources as of the revision date below. Classification appears to depend on the presentation and the claim rather than on the polysaccharide itself. | — |
| EU | unclassified | Not established from public sources as of the revision date below. Annex XVI of the MDR is framed around filling by injection, and whether a non-shaping solution falls under that framing could not be confirmed here. | — |
| US | unclassified | Not established from public sources as of the revision date below. The dermal implant approvals found in the agency device database are for crosslinked products; no equivalent record was found for a non-crosslinked preparation. | — |
| JP | unclassified | Not established from public sources as of the revision date below. | — |
| CN | unclassified | Not established from public sources as of the revision date below. | — |
| VN | unclassified | Not established from public sources as of the revision date below. | — |
Limitations & open questions
Preparations grouped under this name differ in molecular weight, concentration and added components, and many products in this category also contain vitamins, amino acids or other agents that the hyaluronan alone does not account for. Injection technique and depth vary between published protocols and are not standardised. The randomised evidence cited here evaluates a specific formulation and does not describe the category.
All statements on this page are drawn from the cited literature. Where a market’s regulatory classification could not be established from public sources, it is marked as not established rather than inferred.
Same molecule, different job
This page and the crosslinked entry describe the same polysaccharide. What separates them is whether it was linked into a network. Without that step there is no gel, no shape holding and no extended residence — so the questions worth asking change from firmness and duration to distribution and frequency.
The category name hides the formulation
Many products sold in this space are not hyaluronan alone. Vitamins, amino acids and other agents are frequently included, and a result reported for such a product cannot be attributed to the hyaluronan by itself. Before carrying a finding across products, establish what else was in the syringe.
Why the regulatory row is empty here but not next door
The device approvals traceable in public records are for crosslinked implants. For non-crosslinked preparations no equivalent record was found. That is a statement about what could be verified, and it is precisely the kind of gap this reference marks rather than fills.