Study Finds Powder-Based CBD Formulation Dramatically Improves Stability Over Oil

According to a study being published in the August issue of the Journal of Pharmaceutical and Biomedical Analysis, and published online ahead of print by the U.S. National Library of Medicine, how cannabidiol (CBD) is formulated plays a major role in how well it holds up over time, with powder-based systems significantly outperforming traditional oil formulations. The study, conducted by researchers from multiple institutions, compared a cyclodextrin-based powder formulation (HP-β-CD) to a commonly used medium-chain triglyceride (MCT) oil system. Over a range of conditions—including heat, light exposure, and long-term storage—the powder formulation consistently preserved more CBD and produced fewer degradation byproducts.

According to the findings, the HP-β-CD complex retained over 90% of CBD under standard conditions, compared to roughly 20% retention in oil when exposed to light. Even at elevated temperatures, the powder system maintained around 86% to 87% of CBD, indicating strong resistance to thermal degradation. By contrast, oil-based formulations showed significantly higher levels of breakdown and impurity formation.

Researchers also found that the powder formulation generated far fewer unwanted byproducts, with degradation levels staying below 1%, compared to as high as 6.2% in oil-based systems. Antioxidant performance was also stronger in the powder format, suggesting improved protection against oxidative damage.

The study notes that CBD is particularly sensitive to environmental factors such as light, heat and oxygen, all of which can reduce potency and alter chemical composition over time. In some cases, degradation may even lead to the formation of unintended compounds, making stability a key concern for both medical and consumer products.

Overall, the results indicate that encapsulating CBD in a cyclodextrin-based powder could significantly extend shelf life and improve product consistency, particularly when compared to widely used oil-based formulations.

The study was conducted by researchers at the East China University of Science and Technology in Shanghai. The full abstract of the study can be found below.

Abstract

Cannabidiol (CBD), a non-psychoactive terpenophenolic compound derived from Cannabis sativa, exhibits broad-spectrum pharmacological activities but is highly susceptible to oxidative, photolytic, and thermal degradation, making it challenging to preserve and use in therapeutics. Therefore, this study compares the preservation efficiency of a powder-based hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion-complex system for cannabinoid stability and solubility and medium-chain triglyceride (MCT) oil, a common lipid-based carrier in commercial formulations. Formulation characterizations, including CBD content (HPLC), color change, solvent residues, moisture, particle size, and zeta potential, were measured. DPPH experiments revealed that the HP-β-CD complex exhibited higher antioxidant activity (89.2%, EC₅₀ = 45.3 µg/mL) than the MCT oil system (83.6%, EC₅₀ = 58.7 µg/mL), with ascorbic acid serving as the control (EC₅₀ = 12.4 µg/mL). Additionally, photostability testing (8000 lux) demonstrated superior CBD retention in the HP-β-CD complex (>90%) compared with MCT oil (∼20%), indicating substantial light-induced degradation in the oil system. HP-β-CD complex retained 92–93% CBD (k = 0.0084 week⁻¹; t₁/₂ = 82.5 weeks) versus 88% in MCT oil. At 40 °C, HP-β-CD complex preserved 86–87% CBD. GC-FID/GC-MS showed that HP-β-CD powder preserved CBD with only trace degradation (<0.1–1.0%). In contrast, MCT oil produced higher cannabinoid by-products (0.1–6.21%), and greater antioxidant degradation (2.5–8.6% vs 0.5–2.1%). The results suggested that CBD degradation follows matrix-dependent kinetics, with cyclodextrin encapsulation significantly reducing the apparent degradation rate constants relative to oil-based solubilization under identical stress conditions.