Clinical study of the bond repair protocol
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 has been the subject of two types of scientific evaluations:
- a double ex-vivo study allowing the effect of the protocol on the hair fibre to be analysed
- a consumer study allowing the perceived efficacy after use to be evaluated
The protocol studied includes:
- Bond Repair Shampoo
- Bond Repair Mask
- Bond Repair Serum
EVALUATION PROTOCOLS
The method
Ex-vivo studies on the hair fibre
Ex-vivo studies are carried out on locks of natural hair of human origin.
This scientific method allows the condition of the hair fibre and its improvement after use of the protocol to be observed precisely.
The protocol consists of:
- analysing the initial condition of the hair fibre
- applying the full routine
- comparing the results with untreated locks or locks treated with a neutral product
Study by SCANNING ELECTRON MICROSCOPY (SEM)
This method is carried out on locks to visualise the surface of the hair and is performed in several steps:
- Analysing the initial condition of the hair fibre
- Bleaching the locks
- Analysing the condition of the locks
- Applying the full protocol
- Observing the effect of the protocol on the hair surface
Observations are carried out on 10 locks using a scanning electron microscope, enabling precise analysis of the hair surface and the condition of the cuticle. The morphology of the hair is then evaluated by a trained expert, according to an evaluation scale.
Evaluation by colorimetry
The protocol consists of monitoring the evolution of the condition of the hair fibre across 3 groups:
- Treated group: bleached locks + treated with the tested products (shampoo, mask & conditioner)
- Positive control (CTR+): bleached, untreated locks
- Negative control (CTR-): unbleached, untreated locks
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 the thiol groups (-SH) in the hair locks, enabling the ability of the protocol to repair the disulphide bonds degraded by bleaching to be evaluated. 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 the hair
2. total thiols after complete reduction of disulphide bonds with sodium borohydride (NaBH4).
The samples are incubated, neutralised and then analysed to quantify the thiols from the absorbance obtained.
STUDY RESULTS
The 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 the lengths and ends is reduced
Hair appears softer and more supple. It is nourished and more resilient.
A usage test was carried out on 44 subjects after 28 days of using the bond repair protocol (Shampoo + Mask + bond repair serum Luxéol), 2 to 3 times per 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 lasting results
*Ex vivo tests, 10 locks, 16 applications of the Protocol (Shampoo, Mask and bond repair serum):
+ 64% surface repair, measured by scanning electron microscopy
+46% deep repair, evaluated by colorimetry
