>> Ascorbic Acid
1. Histopathological, morphometric and stereological studies of ascorbic acid and magnesium ascorbyl phosphate in a skin care formulation.
Silva, Maia Campos, International Journal of Cosmetic Science, Vol 22 Issue 3, Article first published online: 7 OCT 2008.
"Ascorbic acid (vitamin C) has been widely used in cosmetics and dermatological formulations due to its inhibitory effect on melanogenesis by
affecting collagen synthesis and scavenger properties. However, ascorbic acid (AA) is quickly oxidized and decomposes in aqueous solution
and to solve this problem, vitamin C derivatives were synthesized."
2. Formulation of ascorbicacid microemulsions with alkyl polyglycosides.
N.Pakpayat, F.Nielloud, R.Fortune, C.Tourne-Peteilh, A.Villarreal, I.Grillo, B.Bataille. Laboratoire de Pharmacie Glalenique, Pharmacotechnie et
Biopharmacie, UFR Pharmacie, Montpellier, France. Available online 20 January 2009.
"Ascorbicacid microemulsions for topical application were developed. In this study, microemulsions were prepared using HLD (hydrophilic
lipophilic deviation) concept to optimise the formulation. From this optimal formulation, the realisation of dilution ternary diagrams leads to obtain
microemulsion zones. In addition, the effects of composition variable on the physicochemical characteristics of each system were investigated.
After optimisation of the microemulsion systems, ascorbicacid was loaded in the formulations. Surface tension and small angle neutron
scattering were used to characterise the surface properties and the structure of the microemulsions. Bicontinuous structure microemulsions
were identified, and the influence of ascorbicacid localisation at the interface leading to modifications of the microemulsion structure was
pointed out. The solubilisation of ascorbicacid, the stabilisation and in vitro transdermal penetration “Frantz cells” of ascorbicacid microemulsions
were studied. Three different microemulsions were envisaged. The results confirmed that these microemulsion systems present a real interest
for formulation and protection of ascorbicacid. Regarding their transcutaneous penetration behaviour, the different microemulsions studied could
be useful for different topical applications. A major location of ascorbicacid found in the epidermis where the decomposition of melanin occurred
indicates that microemulsion could be considered as a suitable carrier system for application of ascorbicacid as a whitening agent. In addition, a
good passage of the drug in the dermis could be interesting for the relative oxygen matrix damage."
3. The Effects of Topical L(+) Lactic Acid and Ascorbic Acid on Skin Whitening.
Walter P.Smith, International Journal of Cosmetic Science Volume 21, Issue 1, pages 33-40, February 1999. Article first published online:24 DEC
"Subjects with medium to dark skin and many exhibiting facial age spots or discolorations participated in this twelve week study to evaluate the
skin whitening ability of lactic and ascorbic acid. Using clinical and biophysical test methods we observed prolonged treatment with 8.8% L(+)
lactic acid resulted in no significant effects on skin pigmentation. However treatment with L(+) lactic acid supplemented with ascorbic acid (1%)
did produce a whitening effect which becomes apparent after three months. These effects were demonstrated clinically by the test panelists,
and trained clinicians, and with objective instrumental methods. We observed a general skin lightening and did see a modest preferential
lightening of age spots with the combination of acids."