Molecular interaction of egg lecithin with iodine

✍ Scribed by Benoy B. Bhowmik; Papiya Nandy

• Book ID: 103905615
• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 383 KB
• Volume: 40
• Category: Article
• ISSN: 1386-1425
• DOI: 10.1016/0584-8539(84)80194-4

✦ Synopsis

At very low concentration (10-100 FM), phosphatidylcholine (egg lecithin) forms a 1: 1 molecular complex with iodine in cyclohexane solvent. The thermodynamic and spectrophotometric properties of this complex have been determined. The thermodynamic values are: K,(24"C) = 7.35 x lo3 1 mol-i, AGo = -22.13 kJ mol-i, AH' = -78.47 kJ mol-i and AS0 = -0.19 kJ mol-i degree-'. The complex shows two absorption bands at 295 and 367 nm and both the bands are red shifted in the solid film. The absorption band at 367 nm is due to the blue shifted visible iodine band whereas the charge-transfer band appears at 295 nm. The calculated ionization potential of egg lecithin from the charge-transfer band is about 6.75 eV.