Stability

• Simulated Gastro Intestinal fluids (SGF, SIF)
• Biorelevant media (FaSSIF and FeSSIF)
• Aqueous buffers at different pH
• Plasma and blood stability
• Dosing formulation

Pre-formulation

• Topical formulations
  • Creams/ointment/gel

Metabolism

1. Metabolic stability/ intrinsic clearance
   • Liver and intestinal microsomes
   • S9 fractions
   • Hepatocytes
   • Direct glucuronidation in liver microsomes using UDPGA
   • Reactive metabolites identification using GSH trapping assay
   • Metabolite finger printing analysis in liver microsomes
     
     
2. Metabolism based drug-drug Interactions
   • CYP inhibition (single point, IC₅₀) using human liver microsomes (HLM)
   • Time dependent CYP inhibition in HLM (IC₅₀ shift, K_i and K_inact)
   • CYP reaction phenotyping (purified rCYPs/microsomes)
   • CYP induction in plateable human hepatocytes
     1. 1A2, 2B6 and 3A4 enzyme activity
     2. mRNA analysis
     3. Cytotoxicity

Permeability/Absorbtion:

• Intrinsic permeability-PAMPA
• Mono and bi-directional transport: CaCo-2 and MDCK cells
• In presence and absence of efflux drug transport inhibitors (P-gp, BCRP and MRP)

Distribution/Binding

• Definitive plasma protein binding
• Microsomal  protein binding
• Brain tissue binding
• Blood-to-plasma concentration ratio (RBC partitioning)

Cytotoxicity

• HepG2 cell line
• Hepatocytes