Formulation evaluation development and validation of simultaneous equation method for estimation of vitamin C and vitamin D in multivitamin lipstick

Abstract

Use of vitamins in cosmetic applications has been increased exponentially during recent years. The objective of the present study involves the formulation and evaluation of multivitamin lipstick containing vitamin C and D. Evaluation parameters such as softening point, breaking load test, pay off test, rancidity, force of application, surface anomalies, skin irritation test, aging stability, solubility test were performed. All the formulations F₁,F₂, F₃ containing Vitamin C and D have better stability and showed good pay off results and were accordingly as per daily intake of the Vitamins. A new UV simultaneous equation method was developed and validated for simultaneous estimation of Vitamin C and D according to ICH Q2 (R1) guidelines. The relationship was found to be linear in the concentration range 15-35µg/mL. Analysis was carried out at its _λmax 242nm for vitamin C and at _λmax 264 for vitamin D. The spectrophotometric method was optimized and validated according to ICH Q2 (R1) guidelines. The developed method was sensitive and the LOQ value was found to be 1.64µg/mL for vitamin C and 3.65µg/mL for vitamin D. All the parameters were within the limits.