3.6. Order ↔ DisorderIntroductory examples

TBT4135 Biopolymers

2

Introductory examples

3

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Melting of DNA monitored by fluorescence

5

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Ribonuclease: Heat denaturation monitored by intrinsic viscosity

Differential scanning calorimetry

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Slow (constant heating)Exo/endothermic peak

Chiroptical methods(Polarometry)

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pH driven denaturation of BSA (bovine serum albumin) at different temperatures

Turbidity (transmittance)

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Heat-driven precipitation of HPMC(Hydroxypropyl methyl cellulose)

RheologyGel melting/setting of fish gelatine

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1. Cool from 30C to 4C(melting)

2. Keep at 4C

3. Heat from 4C to 30C(setting)

Other methods

• Circular dichroism (ellipsometry)• Diffusion coefficient• Sedimentation coefficient (ultracentrifuge)• Light scattering (X-ray scattering): RG, A2

• Osmometry (A2)• NMR

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Prion protein

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Gelation/crystallisation of polysaccharides

• Alginates: Chain dimerisation with Ca+

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• ϰ-carrageenan: Gelation with K+

• Agarose: Chain association and gel formation by cooling