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mathematical model of the motion of colloidal particles in an aqueous medium is created. It is shown that Brownian motion plays the dominant role in the movement of colloidal particles with the diameter less than some critical value. 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N0# 2R;08P@A0=# 548<C<A4# {# ?V'# H3<# D548<C4A<<# 10A;@2A@K# r2?21432# - 50FAK4# F<;N43;<<# C2;@<L# Al2O3 (A # %6&&{-20 !JY# <# CdS (A # %6($&{-20 !JY# - D13<@ # &{{# A?# 96 !"#$% !"#$##!#!"#$#%&'()*!+&",)-).##/!0)$ XXVI/!1231/!47 (136) ;00@54@;@5D4@# S-N0@4AL<28D# C2;@<L# {# ?V'# !8G# 50FA0=# F<;N43;<<# C2;@<L# Au (+ # **6%&{ 20 !JY# 13<@<C4;1<=# F<2?4@3# ;00@54@;@5D4@# S-N0@4AL<28D# C2;@<L6#N345KO2PQ4?D#&{{#?V'# /21#N30G58G4@;G#32M?43AK=#Xss41@#5#F<A2?<14#2B34B2L<<#A2A0C2;@<L' n<R8<0B32s<C4;1<4#;;K81<) 1. Izaguirre J.A., Catarello D.P., Wozniak J.M., Skeel R.D. // J. Chem. Phys. 2001. Vol. 114. p. 2090-2098. 2. Visser J. // Adv. Colloid and Interface Sci. 1972. No. 3. p. 331-363. !"#$%%' -'E'#232N2456#-'r'#.D32F0526#W'V'#73@05 :0;;<=;1<=#><?<10-@4>A080B<C4;1<=#DA<543;<@4@#<?'#!'E'.4AF4844526#.0;1526#:0;;<G "%f4&'(&) ,*-'(1'gh) '*'"4*51(3) ,*-'&1(1*) () /*!,*3&$1(4&50() "%(,&!"$)2%#),!1-2(*-'"51(0( '*) "5'"$& !(&,%&,gh) V# F2AA0=# 32R0@4# RK8<# ;<A@4M<3052AK# B<F30s0RAK4# <# B<F30s<8IAK4# A2A0C2;@<LK# ?2BA4@<@2'# nK80# N3054F4A0# <;;84F052A<4# D;@0=C<50;@<# 1# 2B34B2L<<# <# ;4F<?4A@2L<<# B<F30s<8IAK># A2A0C2;@<L# Fe3O4 5# 50FA0?# 32;@503<@484'# V# 32R0@4# RK82# 32;;?0@34A2# 50M?0JA0;@I#518PC4A<G#A2A0C2;@<L#?2BA4@<@2#5#C2;@<LK#;0N08<?432#?080CA0=#<#B8<108450=# 1<;80@#qPLGAY#<#32;N34F484A<4#?2BA<@AK>#C2;@<L#5#0R32MDPQ<>;G#B<R3<FAK>#C2;@<L2>'# In the present work hydrophobic and hydrophilic nanoparticles of magnetite were synthesized. The stability to aggregation and sedimentation of hydrophilic nanoparticles Fe3O4 in aqueous solvent study was conducted. In the present work the inclusion of nanoparticles of magnetite in the particles of poly (lactic-co-glycolic acid) and the distribution of magnetic particles in the resulting hybrid particles were considered. .2BA<@AK4# A2A0C2;@<LK# A2>0FG@# O<30104# N3<?4A4A<4# 50# ?A0B<># 0@32;8G># ?4F<L<AK# <# N30?KO84AA0;@<'# V# ?4F<L<A4# N3<?4AGP@;G# 5# 12C4;@54#10A@32;@A0B0#;34F;@52#5#?2BA<@A0-34M0A2A;A0=#@0?0B32s<<#q.:/Y6# 5#12C4;@54#@32A;N03@A0B0#2B4A@2#F8G#A2N32584AA0=#F0;@251<#84123;@54AAK># ;34F;@5#<#@'F'#V#N30?KO84AA0;@<#50M?0JA0#N3<?4A4A<4#?2BA<@AK>#C2;@<L# 5# 12C4;@54# 0;A05K# F8G# N013K@<=# sDA1L<0A28IA0B0# A2MA2C4A<G6# # 5# 12C4;@54# 0;A05K#F8G#;0MF2A<G#?2BA<@AK>#J<F10;@4=#<#@'F'# !8G# ?4F<L<A;1<># N3<?4A4A<=# ?2BA<@AK># A2A0C2;@<L# 52JADP# 308I# <B324@# 50M?0JA0;@I# ;0MF2A<G# D;@0=C<5K># 10880<FAK># 32;@50305# C2;@<L6# R<0;05?4;@<?0;@I6# 2# @21J4# 50M?0JA0;@I# N3<;04F<A4A<G# 541@03AK># 10?N0A4A@05#1#C2;@<L2?' [;0R04#?4;@0#5#3GFD#?2BA<@AK>#A2A0?2@43<2805 M2A<?2P@#A2A0C2;@<LK# ?2BA4@<@2# qFeO·Fe2O3Y# 5# 5<FD# <># F0;@DNA0;@<6# 5K;010=# @4>A080B<CA0;@<# N30L4;;05#N08DC4A<G#<#A<M10=#@01;<CA0;@<#F8G#J<5K>#03B2A<M?05' 48IP# F2AA0=# 32R0@K# RK80# <;;84F052A<4# D;@0=C<50;@<# 1# 2B34B2L<<# <# ;4F<?4A@2L<<#B<F30s<8IAK>#A2A0C2;@<L#Fe3O4 5#50FA0?#32;@503<@4846#2#@21J4# ;0MF2A<4# A2A0C2;@<L# A2# 0;A054# s23?2L45@<C4;1<# N3<4?84?K># N08<?4305# qR<032M82B24?K>6#R<0;05?4;@<?K>6#A<M10@01;<CAK>Y#F8G#.:/-F<2BA0;@<1<' 97