Process for preparing solid lipid sustained release nanoparticles for delivery of vitamins

A process for preparing solid lipid nanoparticles, said process comprising the following steps:

• i) preparing a lipid mix by melting at least one lipid selected from the group consisting of glycerides and fatty acids;
• ii) preparing an aqueous emulsifier mix by admixing at least one emulsifier and water followed by heating at a temperature at least equal to the melting point of the selected lipid of step (i) and maintaining the said temperature for desired time interval;
• iii) adding at least one vitamin to the lipid or lipid mix to obtain a solution or dispersion;
• iv) mixing the lipid mix of step (iii) with the aqueous emulsifier mix of step (ii) to obtain a hot microemulsion;
• v) stirring the hot micro-emulsion of step (iv) and simultaneously maintaining the temperature at the temperature of the lipid mix;
• vi) adding microemulsion of step (v) to the ice cold water in 1:1 ratio;
• vii) stirring the mixture of step (vi) at 5000 rpm for 1.5 to 3 hours;
• and
• viii) obtaining an aqueous dispersion of solid lipid nanoparticles having a particle size in the range of 5 nm to 500 nm, preferably 5 nm to 250 nm.