Pectin atomic force microscopy

Round A, MacDougall AJ, Ring SG, Morris VJ. Unexpected branching in pectin observed by atomic force microscopy. Carbohydr Res 1997 303 251-253. 

Sriamornsak P, Thirawong N, Nunthanid J, Puttipipatkhachorn S, Thongborisute J, Takeu-chi H (2008) Atomic force microscopy imaging of novel self-assembling pectin-liposome nanocomplexes. Carbohydr Polym 71 (2) 324—329 Takeuchi H, Yamamoto H, Niwa T, Hino T, Kawashima Y (1994) Mucoadhesion of polymer-coated liposomes to rat intestine in vitro. Chem Pharm Bull 42(9) 1954-1956 Takeuchi H, Yamamoto H, Niwa K, Hino T, Kawashima Y (1996) Enteral absorption of insulin in rats from mucoadhesive chitosan-coated liposomes. Pharm Res 13 896-901 Takeuchi H, Kojima H, Yamamoto H, Kawashima Y (2000) Polymer coating of liposomes with a modified polyvinyl alcohol and their systemic circulation and RES uptake in rats. J Control Rel 68(2) 195-205... 

Even today, the resolution of the method is not good and occasional branch points can be missed. This is particularly the case where occasional branch points giving rise to long branches are involved, as with pectin, where they showed up only in the atomic force microscopy of single molecules. Similarly, examination of single molecules of amylose by atomic force microscopy reveals occasional branch points (1 residue in 10 ), well below the resolution of methylation analysis. ... 

There have been a number of other papers on the hydration of biopolymers the effects of the degree of methylation of pectins on the proton relaxation times of water have been measured 50 l70 relaxation has been used to examine the hydration of bovine and caprine casein,51--54 and solid-state NMR combined with atomic force microscopy has been used to examine the influence of water on the nanomechanical behaviour of cutin.55 The effects of locust bean gum on water diffusion in sugar solutions has shown little effect,56 and the effects of gellan gum hydrogel structure on restricted diffusion has also been considered.57... 

Atomic force microscopy height images of samples before (left) and after 30 h ultraviolet irradiation (right) (a) pectin (PEC), (b) PEC/polyvinylpyrrolidone (PVP) (80/20), and (c) PEC/ PVP (60/40). (Reproduced from Kowalonek, J., and Kaczmarek, H. 2010. Studies of pectin/ polyvinylpyrrolidone blends exposed to ultraviolet radiation. European Polymer Journal 46 345-353 with permission from Elsevier.)... 

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