Vesicles, Bilayers, Micelles Through H-Bonding

21b were also found to gelate nonpolar aliphatic hydrocarbons including n-hexane, cyclohexane, n-heptane, n-octane, and n-decane. 

SPR (surface plasmon resonance) was used to probe the interactions between the vesicles. When one of the LUVs was bound to the surface of an SPR substrate, the addition of complementary LUVs produced noticeable concentration dependent signals whereas no signals were observed in the case of the control LUVs. Cryo-TEM was used to check whether mixing of 5 % TM-PE and 5 % TCA-PE LUVs 

AFM images of NDI-1 solutions in water (Fig. 6.38a) revealed the presence of spherical objects with heights and widths of (3.5 0.2) nm and 50-70 nm, respectively. TEM images (Fig. 6.38b) similarly showed the presence of spherical stmctures (diameter 50-80 nm) with hollow interiors. These microscopic observations thus clearly indicated the presence of vesicular structures resulting from NDI-1. 

Interestingly, the electron deficient NDI chromophores could accommodate electron rich, water insoluble pyrene in the vesicular membrane through intercalation in a stoichiometric ratio. The CT interactions (as evident from the red coloration of the solution) thus provided an additional stabilization but did not disrupt the hydrogen-bonding framework between the hydrazide moieties as found from the FTIR studies. Moreover, pyrene intercalation resulted in a 2D-to-lD vesicle-to-fiber transition and upon prolonged standing (2-3 days), the red solution turned to be more viscous and above a threshold concentration (5 mM of each component), a transparent red gel (Fig. 6.39) was obtained. TEM images (Fig. 6.39) recorded for the gel revealed the presence of micrometer-sized fibers, in clear contrast to the spherical vesicles observed for NDI-1. 

Sijbesma RP, Beijer FH, Bmnsveld L, Folmer BJB, Hirschberg JFIK, Lange RFM, Lowe JKL, Meijer EW (1997) Science 278 1601 

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