title: Role of genetic algorithms and artificial neural networks in predicting the phase behavior of colloidal delivery systems.
abstract: OBJECTIVE
  A genetic neural network (GNN) model was developed to predict the phase behavior of microemulsion (ME), lamellar liquid crystal (LC), and coarse emulsion forming systems (W/O EM and O/W EM) depending on the content of separate components in the system and cosurfactant nature.
  
  
  METHODS
  Eight pseudoternary phase triangles, containing ethyl oleate as the oil component and a mixture of two nonionic surfactants and n-alcohol or 1,2-alkanediol as a cosurfactant, were constructed and used for training, testing, and validation purposes. A total of 21 molecular descriptors were calculated for each cosurfactant. A genetic algorithm was used to select important molecular descriptors, and a supervised artificial neural network with two hidden layers was used to correlate selected descriptors and the weight ratio of components in the system with the observed phase behavior.
  
  
  RESULTS
  The results proved the dominant role of the chemical composition, hydrophile-lipophile balance, length of hydrocarbon chain, molecular volume, and hydrocarbon volume of cosurfactant. The best GNN model, with 14 inputs and two hidden layers with 14 and 9 neurons, predicted the phase behavior for a new set of cosurfactants with 82.2% accuracy for ME, 87.5% for LC, 83.3% for the O/W EM, and 91.5% for the W/O EM region.
  
  
  CONCLUSIONS
  This type of methodology can be applied in the evaluation of the cosurfactants for pharmaceutical formulations to minimize experimental effort.
authors.affiliation: School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia. nena@usm.my
authors.forename: S
authors.initials: S
authors.lastname: Agatonovic-Kustrin
authors.forename: R G
authors.initials: RG
authors.lastname: Alany
mesh_terms: D000465:Algorithms; D002626:Chemistry, Pharmaceutical; D003102:Colloids / Q000737:chemistry / Q000493:pharmacokinetics; D016503:Drug Delivery Systems / Q000379:methods; D008957:Models, Genetic; D016571:Neural Networks, Computer; D011237:Predictive Value of Tests; D013501:Surface-Active Agents / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D003102:Colloids; D013501:Surface-Active Agents