title: Interfacial film stabilized W/O/W nano multiple emulsions loaded with green tea and lotus extracts: systematic characterization of physicochemical properties and shelf-storage stability.
abstract: OBJECTIVE
  Multiple emulsions have excellent encapsulating potential and this investigation has been aimed to encapsulate two different plant extracts as functional cosmetic agents in the W/O/W multiple emulsions and the resultant system's long term stability has been determined in the presence of a thickener, hydroxypropyl methylcellulose (HPMC).
  
  
  METHODS
  Multiple W/O/W emulsions have been generated using cetyl dimethicone copolyol as lipophilic emulsifier and a blend of polyoxyethylene (20) cetyl ether and cetomacrogol 1000® as hydrophilic emulsifiers. The generated multiple emulsions have been characterized with conductivity, pH, microscopic analysis, phase separation and rheology for a period of 30 days. Moreover, long term shelf-storage stability has been tested to understand the shelf-life by keeping the generated multiple emulsion formulations at 25 ± 10°C and at 40 ± 10% relative humidity for a period of 12 months.
  
  
  RESULTS
  It has been observed that the hydrophilic emulsifiers and HPMC have considerably improved the stability of multiple emulsions for the followed period of 12 months at different storage conditions. These multiple emulsions have shown improved entrapment efficiencies concluded on the release rate of conductometric tracer entrapped in the inner aqueous phase of the multiple emulsions.
  
  
  CONCLUSIONS
  Multiple emulsions have been found to be stable for a longer period of time with promising characteristics. Hence, stable multiple emulsions loaded with green tea and lotus extracts could be explored for their cosmetic benefits.
authors.affiliation: Department of Pharmacy, Faculty of Pharmacy and Alternative Medicine, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan. tariqmahmood750@gmail.com.
authors.forename: Tariq
authors.initials: T
authors.lastname: Mahmood
authors.forename: Naveed
authors.initials: N
authors.lastname: Akhtar
authors.forename: Sivakumar
authors.initials: S
authors.lastname: Manickam
mesh_terms: D003358:Cosmetics / Q000008:administration & dosage* / Q000737:chemistry; D045703:Emulsifying Agents / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D000070116:Lotus / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D010936:Plant Extracts / Q000008:administration & dosage* / Q000737:chemistry; D013662:Tea / Q000737:chemistry*
chemical_list: D003358:Cosmetics; D045703:Emulsifying Agents; D004655:Emulsions; D010936:Plant Extracts; D013662:Tea