CLINICAL STUDY
Bond Repair Protocol
Repaired, stronger and nourished hair
The Bond Repair Protocol was developed to repair hair.
Thanks to a combination of complementary treatments, it acts directly on the hair fibre to restore its structure, improve its resilience and restore softness, suppleness and shine to hair.
Scientifically evaluated efficacy
The repair protocol was the subject of two types of scientific evaluation:
- a double ex-vivo study allowing analysis of the effect of the protocol on the hair fibre
- a consumer study to evaluate perceived efficacy after use
The protocol studied comprises:
- Bond Repair Shampoo
- Bond Repair Mask
- Bond Repair Serum
EVALUATION PROTOCOLS
The method
Ex-vivo studies on the hair fibre
The ex-vivo studies are conducted on strands of natural human hair.
This scientific method allows precise observation of the condition of the hair fibre and its improvement after use of the protocol.
The protocol consists of:
- analyse the initial condition of the hair fibre
- apply the full routine
- compare the results with untreated strands or strands treated with a neutral product
Study by SCANNING ELECTRON MICROSCOPY (SEM)
This method is carried out on strands to visualise the hair surface and is performed in several steps:
- Analyse the initial condition of the hair fibre
- Bleach the hair strands
- Analyse the condition of the strands
- Apply the full protocol
- Observe the effect of the protocol on the hair surface
Observations are carried out on 10 strands using a scanning electron microscope, allowing precise analysis of the hair surface and the condition of the cuticle. Hair morphology is then evaluated by a trained expert using an assessment scale.
Colorimetric evaluation
The protocol consists of monitoring the evolution of the hair fibre condition across 3 groups:
- Treated group: bleached strands + treated with the tested products (shampoo, mask & conditioner)
- Positive control (CTR+): bleached, untreated strands
- Negative control (CTR-): unbleached, untreated strands
Measurements are taken at 5 time points: before bleaching (T-1), after bleaching (T0), then after 1, 8 and 16 applications (T1, T8, T16).
An Ellman test (colorimetric method) is carried out to quantify thiol groups (-SH) in hair strands, allowing evaluation of the protocol's capacity to repair disulphide bonds degraded by bleaching. Ellman's reagent reacts with free thiols to produce a yellow anion measurable by spectrophotometry at 412 nm. The absorbance intensity is directly proportional to the thiol content.
Two measurements are taken:
1. Free thiols naturally present in hair
2. Total thiols after complete reduction of disulphide bonds with sodium borohydride (NaBH4).
The samples are incubated, neutralised and then analysed to quantify thiols from the absorbance obtained.
STUDY RESULTS
Results
The studies demonstrate a visible improvement in the quality of the hair fibre:
- the fibre is repaired and strengthened*
- the surface of the hair is smoother*
CONSUMER RESULTS
The damaged appearance of lengths and ends is reduced
Hair appears softer and more supple. It is nourished and more resilient.
A usage test was conducted on 44 subjects after 28 days of using the Bond Repair Protocol (Shampoo + Mask + Bond Repair Serum Luxéol), 2 to 3 times a week.
Repaired, nourished and visibly more beautiful hair
97% find their hair revitalised, hydrated and nourished
95% find their hair repaired
95% find that the protocol restores the hair fibre
97% find their hair more beautiful
97% find their split ends less visible
90% notice immediate and long-lasting results
*Ex-vivo tests, 10 strands, 16 applications of the Protocol (Shampoo, Mask and Bond Repair Serum):
+64% surface repair, measured by scanning electron microscopy
+46% in-depth repair, evaluated by colorimetry
