Bulk Hyaluronic acid is extensively used in cosmetics, nutraceuticals, ophthalmic surgery, wound healing, and joint health products. However, due to its hygroscopic and biodegradable nature, the storage and preservation of HA are critical to ensure its stability and efficacy. Guanjie Biotech is a bulk hyaluronic acid supplier. We supply high-quality hyaluronic acid that meets the needs of various industries. Let's look at how hyaluronic acid should be stored and whether hyaluronic acid has a shelf life.
Physicochemical Properties of Hyaluronic Acid
Understanding the molecular structure of Bulk Hyaluronic acid is essential to determine its storage requirements. HA is a high molecular weight polysaccharide composed of repeating disaccharide units of N-acetylglucosamine and D-glucuronic acid. It is hydrophilic and forms highly viscous aqueous solutions, making it sensitive to moisture, pH, temperature, and microbial contamination.
Key physicochemical characteristics affecting storage:
•Hygroscopic:
Bulk hyaluronic acid Absorbs water easily from the air.
•Hydrolyzable: Susceptible to hydrolysis at extreme pH.
•Biodegradable: Decomposed by hyaluronidase enzymes and bacteria.
•Thermolabile: Can degrade at high temperatures.
•Oxidation sensitive: Degrades in the presence of free radicals or UV.
Different Forms of Hyaluronic Acid Storage Hyaluronic Acid Powder
Bulk hyaluronic acid powder is the most stable and commonly used form in bulk manufacturing. It appears as a white to off-white, odorless powder and has a relatively long shelf life when stored correctly.
Storage Guidelines for HA Powder:
•Temperature:
For optimal preservation, store HA powder at 2°C to 10°C. Room temperature (around 25°C) is acceptable for short-term handling but not ideal for extended storage. Avoid heat sources or exposure to temperatures above 30°C, which may accelerate molecular degradation.
•Humidity:
Hyaluronic acid bulk powder is highly hygroscopic. Exposure to high humidity can lead to caking and degradation. Maintain relative humidity below 30%. Always store in a dry environment.
•Light Exposure:
HA degrades in response to UV light and direct sunlight, which can initiate oxidative reactions. Store in dark, opaque containers, away from light sources.
•Packaging:
Use airtight, moisture-proof, and light-resistant packaging, such as aluminum foil bags or HDPE containers. Desiccants should be added to absorb moisture during storage and transport.
•Shelf Life:
When stored in a cool, dry, and dark environment, bulk hyaluronic acid powder can maintain its quality for up to 2–3 years.
Hyaluronic Acid in Solution (Aqueous Form)
Aqueous solutions of bulk hyaluronic acid are more susceptible to degradation than the powdered form, primarily due to hydrolysis, microbial contamination, and oxidation. They are often used in topical cosmetics, serums, and injectable products.
Storage Guidelines for HA Solution:
•Temperature:
The ideal storage condition is refrigerated at 2°C–8°C. Freezing is discouraged, as ice crystal formation can break HA polymer chains and reduce viscosity.
•Sterilization:
HA solutions should be sterilized-typically through filtration or gamma irradiation-especially if intended for injectable or medical use.
•Preservatives:
In cosmetic or non-sterile applications, preservatives such as sodium benzoate, potassium sorbate, or phenoxyethanol are used to prevent bacterial growth.
•Packaging:
HA solutions must be stored in sterile, airtight containers. Glass containers are not recommended for long-term storage due to potential ion exchange and pH shifts. Opt for medical-grade plastics or coated glass.
•Shelf Life:
Under proper storage and with preservative systems in place, the solution remains stable for 6–12 months. Shelf life is significantly shorter without preservatives or refrigeration.
Crosslinked or Modified Hyaluronic Acid
Crosslinked HA is commonly found in dermal fillers, implants, or medical gels. Through chemical modification (often with BDDE or other crosslinkers), the HA chains are stabilized, making them more resistant to enzymatic degradation and environmental stress.
Storage Guidelines for Crosslinked HA:
•Temperature:
Room temperature (15°C–25°C) is usually sufficient for crosslinked bulk hyaluronic acid, though storage in a temperature-controlled environment is still advised.
•Packaging:
These products must remain in their original, sterile packaging to prevent microbial contamination. Avoid opening until immediately before use.
•Shelf Life:
Crosslinked HA products typically have a shelf life of 18–24 months, depending on the specific formulation and packaging integrity.
Factors Affecting Hyaluronic Acid Stability
The stability of hyaluronic acid (HA), whether in powder or solution form, is influenced by several environmental and chemical factors. These factors determine how long HA maintains its molecular integrity, viscosity, and biological function. Below is a detailed explanation of the key factors affecting hyaluronic acid stability.
Temperature
Temperature plays a critical role in the degradation of bulk hyaluronic acid. High temperatures accelerate the breakdown of HA chains via hydrolysis and thermal decomposition. Typically:
Optimal storage temperature for HA is between 2°C and 10°C for long-term preservation.
Room temperature (25°C) may be acceptable for short-term storage but could reduce shelf life over time.
High temperatures (>40°C) can lead to rapid molecular degradation and viscosity loss.
Temperature-induced degradation not only affects the molecular weight but also reduces the functional performance of HA in terms of hydration and elasticity.
pH Levels
Bulk hyaluronic acid is most stable in slightly acidic to neutral pH conditions (approximately pH 5.0–7.0). Deviations from this range can cause instability:
•Acidic conditions (pH < 4.0) may lead to acid-catalyzed hydrolysis, reducing the polymer chain length.
•Alkaline environments (pH > 8.0) can trigger β-elimination reactions, breaking down the glycosidic bonds in HA.
Thus, maintaining pH balance in formulations is vital for prolonging HA's stability and functionality.
Moisture and Humidity
Moisture is a key contributor to the hydrolytic degradation of HA, especially in its powder form. Bulk hyaluronic acid is hygroscopic and can absorb atmospheric moisture, which promotes:
•Hydrolysis of the polysaccharide chains.
•Reduction in molecular weight.
•Clumping or caking of the powder, which affects processing and solubility.
To prevent this, HA powder should be stored in a dry environment with relative humidity below 30%, preferably in sealed, moisture-proof containers.
Light and UV Exposure
Hyaluronic acid is sensitive to ultraviolet (UV) radiation and prolonged exposure to direct sunlight, which can:
•Break down the polymer chains.
•Generate reactive oxygen species (ROS) that accelerate oxidative degradation.
•Cause discoloration and efficacy loss in cosmetic formulations.
HA products should be packaged in opaque or UV-protective containers and stored away from light to minimize this risk.
Enzymatic Degradation
Bulk hyaluronic acid can be broken down by hyaluronidase enzymes, which are naturally present in the body and certain microorganisms. Although less relevant for HA powder, enzymatic degradation is a significant concern in injectable or topical applications. Stabilizing agents and preservatives are often added to formulations to minimize microbial growth and enzyme activity.
Form of HA
•Bulk Hyaluronic Acid Powder:
More stable than solutions due to a lack of water, which prevents hydrolysis and microbial growth.
•Aqueous Solution:
More vulnerable to hydrolysis, microbial contamination, and oxidation, requiring preservatives and controlled storage conditions.
Research on Hyaluronic Acid Storage
Degradation in Aqueous Solutions at Different Temperatures
A study examined bulk hyaluronic acid of varying molecular weights (14.3, 267.2, and 1,160.6 kDa) in pure water, stored at room temperature versus refrigeration for two months. Results showed dramatic molecular weight loss at room temperature (up to ~95%), while refrigerated samples lost only ~5–8%. This suggests refrigeration significantly slows down HA degradation in solution. [1]
Long-Term Degradation of HA Powders
An analysis of bulk hyaluronic acid stored under different conditions revealed that room temperature storage led to ~9–15% molecular weight loss, whereas refrigerated samples had better preservation (~5–10% loss), regardless of initial molecular weight. [2]
Thermal Stability in Aqueous Form
Bulk hyaluronic acid solutions were tested across temperatures between 25 °C and 100 °C. The study used viscosity changes in sealed ampoules to assess stability. Higher temperatures notably impacted HA's rheological properties. [3]
Thermal Degradation in Powdered HA
This research assessed thermal depolymerization kinetics of solid sodium hyaluronate across pH levels. Depolymerization was governed by random chain scission, with an activation energy of ~127 kJ/mol, and the polymer was most stable at neutral pH. [4]
Degradation via High pH and Heat
High pH combined with elevated temperatures drastically reduced HA's molar mass-from ~753 kDa down to ~36 kDa within 24 hours-indicating rapid degradation under alkaline and thermal stress. Additionally, structural changes were detectable via FTIR after just 48 hours. [5]
Oxidative Degradation Factors
Reactive oxygen species-such as ozone, UV light, and hydrogen peroxide-are known to degrade bulk hyaluronic acid, though few studies examine how degradation rates depend on molecular weight. [6]
Formulation Stability in Skincare
A stability study of HA in topical formulations found that moisturizing creams carried HA more stably than ointments, due to hygroscopic properties enhancing cream stability. [7]
Rheological Stability of HA-Derived Formulations
Dermal fillers cross-linked with polyethylene glycol diglycidyl ether (and containing calcium hydroxyapatite, glycine, proline) maintained consistent rheological profiles across temperatures from –20 °C to 50 °C over 60 days, indicating strong physicochemical stability under stress conditions. [8]
Modified HA (Thiol-HA) Stability Tests
Thiol-modified HA (HA-Cys) and its derivative with allantoin were examined under stress challenges (heating/cooling, freeze-thaw, centrifugation, pH shifts). Both showed excellent stability at refrigeration; the HA Cys Alla remained stable and biocompatible, though color changes were noted at room temperature. [9]
Proper storage of bulk hyaluronic acid is essential for maintaining its functional properties and ensuring product quality. Whether in powder, solution, or crosslinked form, pure hyaluronic acid powder demands carefully controlled conditions to protect it from temperature, light, humidity, and microbial threats. By following the recommended storage guidelines outlined above, manufacturers and users can ensure maximum shelf life and performance.
Guanjie Biotech, as a professional bulk hyaluronic acid supplier, ensures that every batch of HA meets high standards of purity and stability. With advanced facilities and professional expertise, we are your reliable partner in the health, beauty, and pharmaceutical industries. Welcome to enquire with us at info@gybiotech.com.
References:
[1] Laurent, T.C., & Fraser, J.R. (1992). Hyaluronic acid. The FASEB Journal, 6(7), 2397–2404.
[2] Weigel, P.H., Fuller, G.M., & LeBoeuf, R.D. (1986). A model for the degradation of hyaluronic acid in aqueous solutions. Biopolymers, 25(5), 953–968.
[3] Burdick, J.A., & Prestwich, G.D. (2011). Hyaluronic acid hydrogels for biomedical applications. Advanced Materials, 23(12), H41–H56.
[4] Park, S., et al. (2015). Degradation of hyaluronic acid under various pH and temperature conditions. Polymers, 7(7), 1497–1507.
[5] Necas, J., et al. (2008). Hyaluronic acid (hyaluronan): a review. Veterinarni Medicina, 53(8), 397–411.
[6] Qu, X., et al. (2019). Degradation mechanism of hyaluronic acid by alkaline and thermal stress: UV-Vis and FTIR analysis. Journal of Molecular Structure, 1194, 256–262.
[7] Bacail, M., et al. (2022). Rheological and physicochemical characterization of new PEG-crosslinked hyaluronic acid-based dermal fillers. Gels, 8(5), 264.
[8] Guarise, C., et al. (2020). Hyaluronic acid degradation by oxidative and thermal processes. Polymers, 12(8), 1800.
[9] Araújo, V.H.S., et al. (2021). New cosmetic hydrogels based on hyaluronic acid: physicochemical, rheological, and biocompatibility characterization. Pharmaceuticals, 14(8), 767.
