Reviving Hair with Micro Proteins

BASF's new low-molecular-weight proteins Nutrilan® Keratin LM and Gluadin® Kera-P LM are presented with strong claims such as deep penetration, repair, strengthening, durability and softness, as well as different claims for high-performance hair care products regarding enhanced protection and renewal of hair structure. The natural keratin building block Nutrilan Keratin LM is derived from animal-source keratins, while Gluadin Kera-P LM, a plant-based alternative to keratin, is BASF's first low-molecular-weight phytokeratin product for the personal care market. Our hair is exposed every day to many stress-creating factors that can cause damage. This includes environmental effects such as UV light and pollution; however, commonly used hair dyes and hair strengthening treatments as well as daily procedures such as combing and styling hair can also cause this. The two new microproteins developed by BASF can now protect hair from these problems both from within and from outside. Gluadin Kera-P LM, with an amino acid spectrum extremely similar to animal-source keratins, is BASF's first low-molecular-weight phytokeratin product for the personal care market. BASF offers two low-molecular-weight proteins, the natural keratin building block Nutrilan Keratin LM, produced with enzymatic, non-GMO methods and capable of cold processing. Recommended dosages are between 0.5% and 2%. They are gluten-free, halal-certified and can be considered for products with EU Ecolabel and Nordic Swan label.

New Microproteins Repair Hair from Within

While many protein hydrolysates have an effect on the hair surface or outer surface, the low-molecular-weight proteins Nutrilan Keratin LM and Gluadin Kera-P LM penetrate deeply from the outer surface into the cortex. Here, they restore the missing protein building blocks of hair and help reduce stress.

Double the Protection on Hair Surface

Microproteins provide protection for the outer surface on the hair surface. Normally free radicals weaken hair, leading to protein degradation, while Nutrilan Keratin LM and Gluadin Kera-P LM reduce the damage hair experiences thanks to their dual protective effects: First, they can capture free radicals to prevent premature hair aging. Second, they reduce oxidative stress-induced damage by eliminating copper binding in hair.

Proof of Concept

Many tests have been performed to support each claim: penetration into the interior (cortex), repair and strengthening of hair and protection of the exterior (epidermis) against free radicals.

Penetration

Confocal fluorescence microscopy provides evidence that the total amount of protein penetrating into the cortex is greater than from high-molecular-weight hydrolysates and that the penetrating proteins remain in the hair even after washing. For measurement, protein hydrolysates were labeled with fluorescein isothiocyanate (FITC). Hair strands from a person with white skin that had not been treated were processed three times with persulfate ("ultra") bleaching, incubated in aqueous solution of labeled protein hydrolysates (1% active; 8 hours), immersed in active surfactant solution (12% Texapon® NSO; 24 and 72 hours) and dried. Deep penetration continued. Hair Repair Hair is a complex composite material composed of α-helical crystalline proteins embedded in non-crystalline amorphous protein material. Differential scanning calorimetry (DSC) is a highly sensitive method for determining the denaturation temperature of human hair protein structure, such as the temperature at which the protein structure breaks after heating. Furthermore, energy (enthalpy) is required for this breakage to be measured. In general, low denaturation temperatures and low denaturation enthalpies are characteristic of more damaged hair. In DSC, denaturation temperature can be seen as an indicator of the durability of the protein matrix, while enthalpy is a measure of the content and structural rigidity of the α-helical material. The potential of the new microproteins to repair damaged hair was measured via DSC. First, hair strands from a person with white skin were damaged by ultra bleaching. Damaged hair treated with aqueous solutions containing protein hydrolysate (5% protein hydrolysate; 24 hours) showed higher denaturation temperature and enthalpy, which was interpreted as hair repair. Based on DSC denaturation temperature results, Gluadin Kera-P LM showed a higher effect in repairing the amorphous protein matrix compared to Nutrilan Keratin LM: Denaturation temperature increased by up to 60% with Gluadin Kera-P LM while it increased by up to 35% with Nutrilan Keratin LM. This may be due to Gluadin Kera-P LM's much lower molecular weight. DSC enthalpy results relate to the integrity of the α-helical protein structure of hair, where Nutrilan Keratin LM exhibited better results. This can be explained through two effects:

Hair Strengthening

Hair is strengthened through several mechanisms. For example; bringing together protein fragments, affecting the matrix or interacting with keratin filaments and thus increasing the stiffness of hair fibers can strengthen hair. Stiffness is defined as the hair volume divided by "the energy required to break the hair fiber"; more energy is required when breaking thicker hair compared to thinner hair to reduce the effect of hair diameter. Hair integrity is measured in terms of stiffness by pulling hair fibers until they break. To measure the durability effectiveness of microproteins, ultra-bleached hair strands from a person with white skin were treated for 24 hours with 5% protein hydrolysate and placebo. Stiffness increased by approximately 20% with Nutrilan Keratin LM. The effect of proteins on hair breakage was measured by gravimetric combing tests: hair of medium-bleached level from a person with white skin was treated with HB-De-179-1 styling product with and without 1% protein hydrolysate. Gluadin Kera-P LM reduced breakage by 20% while Nutrilan Keratin LM reduced it by 50%. Thus, it was shown that LM protein hydrolysates make hair more resistant to mechanical stress. Medium-bleached hair from a person with white skin with styling product with/without 1% Nutrilan® Keratin LM/1% Gluadin® Kera-P LM; gravimetric combing test. Finally, the effect of microproteins on combability was measured by combing tests performed on dry hair after five repeated treatments: Untreated hair from a person with white skin was treated five times with HB-DE-173-12 shampoo with/without 1% protein hydrolysate and then dried. Gluadin Kera-P LM reduced the energy required for combing by 15 percent, while Nutrilan Keratin LM reduced it by 20 percent. When these results are considered together, It is concluded that Nutrilan Keratin LM strengthens α-helical protein with increased structural rigidity and hair stiffness, while Gluadin Kera-P LM restores non-helical protein by filling the matrix.

Epidermis Protection

During oxidative processes such as bleaching, coloring and sun exposure, copper facilitates the formation of free radicals that cause protein degradation on the outer surface. A large portion of copper comes from water sources used to wash hair. Swimming in treated pools can result in intake of very high levels of copper. In collaboration with GEMATRIA Test Lab GmbH, a free radical research specialist, BASF has shown that less copper ions attach to hair after treatment with Nutrilan Keratin LM or Gluadin Kera-P LM. Hair from a person with white skin that had been ultra-bleached twice was cut into 1 cm length pieces. 10 mg samples were incubated for 20 minutes with aqueous solutions containing 5% protein hydrolysate (1% active) or placebo and then rinsed. Thereafter, the strands were incubated in 40 mm CuSO4 solution for 10 minutes to determine the amount of copper applied to the hair, rinsed twice and placed in an electron spin resonance (ESR) spectrometer (Magnettech MS 300). Nutrilan Keratin LM reduced copper adhesion to the epidermis by 20%, while Gluadin Kera-P LM reduced it by 30%. Photometric measurement was used to determine protection against free radicals. Results were compared with Trolox, a water-soluble vitamin E analog, and showed that LM protein hydrolysates are highly active antioxidants, particularly in high pH applications.

Conclusion

The low-molecular-weight proteins Nutrilan Keratin LM and Gluadin Kera-P LM penetrate deeply from the outer surface into the cortex. On the hair surface, they provide dual protective effect by protecting the outer surface as a result of reducing copper adhesion to hair and capturing free radicals, reducing damage caused by oxidative stress and preventing premature hair aging. Bilinç Barçın Ersun / BASF Türkiye ve Orta / Doğu Bölgesi Kişisel Bakım / Marketing Manager / BASF Türk Kimya Sanayi ve Ticaret Ltd. Şti.