Comparing the Olfactory Perception of a Fragrance-Loaded SpECs Over Time

The human olfactory system plays a crucial role in sensory perception, influencing emotional states, memory, and interpersonal interactions(1). Fragrance durability and intensity are critical factors in the evaluation of perfumes and other scented products. The ability of fragrance formulations to maintain consistent scent intensity over time is a major contributor to a product's overall efficacy and consumer satisfaction.

SporoSpECsin exine capsules (SpECs), are extracted from either pollen or plant spores in the form of empty porous microcapsules penetrated by nano-diameter sized channels. These channels enable a variety of active ingredients to be loaded into the SpECs chambers; hence, giving universality to the system to encapsulate such as a variety of antibody fragments, oils and proteins and peptides. The preparation that is to be used in this study has been provided to us as a gift by Sporomex Ltd, UK that is presently being used as a cosmetic preparation commercially, and has been investigated as a taste masking agent(2) and for oral pharmaceutical delivery(3).

It is unknown if fragrance loading of these SpECs will enhance the longevity of the fragrance on the skin. This study aims to evaluate the olfactory perception of a SpECs-based fragrance delivery system over an 8-hour period. The study will compare subjective ratings of the fragrance's intensity by participants and an independent examiner. This randomized, double-blind crossover trial will provide insights into the effectiveness of SpECs as a fragrance delivery medium, while also considering the influence of skin chemistry and time on olfactory perception. By eliminating patient variability, crossover studies can be more efficient than equivalently sized parallel group trials, where each participant receives only one treatment. Hence, treatment effects can be measured with greater accuracy using the same number of participants.

Type of Study Pilot randomized, double-blind crossover trial Participants

• Sample size: 10 female participants.
• Inclusion criteria:

• Females aged between 18 and 45 years.
• No history of olfactory impairment, allergies to pollen or fragrances, or skin conditions.
• Exclusion criteria:

• Current use of medications that affect olfactory function (e.g., antihistamines).
• Pregnancy or breastfeeding.
• Any active upper respiratory tract infection within 2 weeks of the clinical trial
• Any known skin allergy. Intervention
• Fragrance delivery system: SpECs loaded with fragrance (50mg/ml perfume) versus fragrance without SpECs
• Application: A smear layer of the fragrance-loaded SpECs will be applied to the wrist of each participant.

Randomization and Blinding

• Participants will be randomized into two groups:

• Group A: Fragrance loaded with a concentration of SpECs grains.
• Group B: Fragrance loaded without SpECs grains.
• Double-blinding: Neither the participants nor the independent examiner will know which preparation of the fragrance will be applied to the skin.

Inclusion criteria

• Females aged between 18 and 45 years.
• No history of olfactory impairment, allergies to pollen or fragrances, or skin conditions.

Exclusion criteria

• Current use of medications that affect olfactory function (e.g., antihistamines).
• Pregnancy or breastfeeding.
• Any active upper respiratory tract infection within 2 weeks of the clinical trial
• Any known skin allergy.