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Small high density lipoprotein subclasses: some of their physico-chemical properties and stability in solution.

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Atmeh R. F., Abd Elrazeq I. O.

Acta Biochimica Polonica

2005

vol. 52

issue 2

515-525

Small high density lipoproteins (SHDL) contribute to the protection from atherosclerosis, but detailed information about their properties is not available yet. We isolated four of the smallest HDL subclasses that contain apoA-I alone, the small lipoprotein A-I (SLpAI), by their separation on gradient polyacrylamide gel followed by electroelution. Their physico-chemical properties were calculated from their displacement in non-denaturing gradient polyacrylamide gel under the effect of electrical potential. The properties are: Stokes' radii 2.96-3.56 nm; molecular masses 42-70 kDa; net negative charge 7.2-13.5; surface charge densities 3139-4069 -esu∙˙cm^(-2); surface potentials 10.6-15.7 -mV; coefficients of friction 5.74-6.90 × 10-8 g∙˙s^(-1); and diffusion coefficients 5.76-6.94 7× 10-7 cm^2∙˙s^(-1). We found that these particles were of low stability as they underwent molecular transformation into larger particles on storage. The estimated dimensions of these particles do not support ellipsoidal shape, therefore, the most probable shape is spherical; consequently, their hydrated characteristics were estimated. We conclude that these particles have high values of negative surface charge and diffusion coefficients, and are of low stability. Their small Stokes' radii were similar to each other and they are spherical and highly hydrated.

ON OBTAINING BINARY POLYELECTROLYTE COMPLEXES OF CHITOSAN BOMBYX MORI WITH COLLAGEN

100%

Rakhimovna Vokhidova N., Shamsiddinovich Khudoyberdiyev S., Nakipovich Nurgaliev I., Sharafovna Rashidova S.

Progress on Chemistry and Application of Chitin and its Derivatives

2023

vol. 28

188-203

We obtained binary polyelectrolyte complexes containing chitosan from Bombyx mori and collagen with a mass ratio of 10:1; 10:2, and 10:3. During the interaction between the macromolecules, due to the compensation of the positive charges of chitosan with the negative charges of collagen, the zeta potential of the solutions of polyelectrolyte complexes changed from +15.2 to +5.67 mV. We revealed the dependence of the size characteristics of the particles of polyelectrolyte complexes on time and the ratio of macromolecules. An examination of the morphology of the films of polyelectrolyte complexes demonstrated that in the evaluated chitosan/collagen mass ratios, non-spherical nanosized particles up to ≤ 60 nm form on the surface of the films. We evaluated the mechanism of formation of complexes by using Fourier-transform infrared spectroscopy and confirmed the findings with density functional theory and molecular dynamics. We found that the particle diameter is inversely proportional to the diffusion coefficient. The results show that the particles are almost uniformly distributed over the surface of the polymer matrix and have a unimodal character. We obtained reproducible results when using a chitosan/collagen mass ratio of 10:2 to dye natural silk. We found that the complexes contribute to increase the intensity and stability of colour relative to soap and friction.

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1 Acta Biochimica Polonica

1 Progress on Chemistry and Application of Chitin and its Derivatives

1 2023

1 2005

1 Abd Elrazeq I. O.

1 Atmeh R. F.

1 Nakipovich Nurgaliev I.

1 Rakhimovna Vokhidova N.

1 Shamsiddinovich Khudoyberdiyev S.

1 Sharafovna Rashidova S.

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Small high density lipoprotein subclasses: some of their physico-chemical properties and stability in solution.

ON OBTAINING BINARY POLYELECTROLYTE COMPLEXES OF CHITOSAN BOMBYX MORI WITH COLLAGEN