كلية الصيدلة

Faculty of Pharmacy

A Thesis For The Degree of Doctor of Philosophy in Pharmaceutical Sciences (Pharmaceutics)/

Includes Bibliographic Referances, p171:196

Abstract.
I
Cosmeceuticals are cosmetic products with biologically active ingredients having a medical or drug‐like benefits, they can be considered as cosmetic actives with therapeutic, disease fighting, or healing properties against degenerative skin conditions. Cosmeceuticals typically claim to improve skin tone, texture, and radiance, while reducing wrinkling. Commonly used substances included in cosmeceutical formulations are described as follows: moisturizing agents, sunscreening agents, vitamins and chemical peeling agents.
The use of sunscreen cosmetic products could help to prevent or to minimize the harmful effects associated with the excessive sun exposure. Sunscreens are the main components of lotions and creams used to prevent UV-induced damage or to ameliorate its harmful effects. Sunscreening agents prevent early wrinkling, sunburns and skin cancer. The relationship between over exposure to sunlight and skin cancer has been widely explored; reduction or avoidance to unhealthy over exposure to sunlight or other sources of UVR appears to be clinically essential in protecting the skin from premature damages.
Photoprotection is an essential prophylactic and therapeutic element. Chemoprevention refers to the use of pharmacological or natural agents to prevent precancerous lesions to reverse invasive cancers or to suppress the process of carcinogenesis. Both photostability and water resistance measurements are mandatory, in the final sunscreen products besides having a pleasant sensory and tactile profiles that enhance the user‘s compliance.
Micropigments are defined as UVB and/or UVA absorbers. Examples are TiO2 (UVB) and ZnO (UVA) with a very weak IR protection. However, they can also be organic compounds like Tinosorb
S. These substances are chemically inert, largely UV stable, efficient even in low concentrations, relatively inexpensive, demanding in formulation development, they are colorless and odorless formula ingredients and are toxicologically safe.
Tinosorb S is the most efficient broad-spectrum UV-absorber having a dual mechanism of action in absorbing and reflecting photons beside its inherent photostability and compatibility with all types of cosmetic filters. Celecoxib, is a potent chemopreventive agent in different cancer types, it has been shown to decrease UVB mediated erythema and inflammation production. Apalight is one of the sun filter boosters and is considered skin-friendly solid actives in sunscreen cosmetics. The present study is an attempt to formulate and evaluate oleogels as cosmetic bases for the chemical sunscreening agent Tinosorb S, together with Celecoxib and Apalight as biological and physical photochemopreventive agents aiming to achieve an effective, photoprotective and preventive effects against UV exposure hazards.
Therefore, the work in this thesis is divided into three chapters:
Chapter I: Formulation of oleogels as cosmetic bases for Tinosorb S.
Chapter II: Formulation of photochemopreventive Tinosorb S oleogel formulae.
Chapter III: In-vivo performance of the optimum photochemopreventive oleogel formula.

Includes CD copy for The Thesis

Text In English and Abstract in Arabic .