Synthesis of magnetic nanoparticles and their dispersions with special reference to applications in biomedicine and biotechnology

•Advantages of biomagnetic particles.•Direct binding of biomolecules and drugs on nanomagnetic particles•Nanomagnetic particles for targeted drug delivery•Self controlled hyperthermia•Synthesis of AgFe composite for antibacterial and antifungal activity•Photodynamic therapy

Biomedical and biotechnological applications of magnetic nanoparticles and their dispersions in liquids are found to be potentially useful. An exponential growth in publications of papers, reviews and patents has been observed. Possibilities of their indiscriminate use on individual as well as environmental health hazards are also investigated. Still, there appears to be a good scope for further research work in the field. Even a small improvement either in preparation method or development of novel nanoparticles may prove to be beneficial in longer run. With this aim in mind, the present review discussed the work carried out in author's laboratory on synthesis and characterization of certain biomagnetic particles and biocompatible fluids composed of these particles. Modified methods were used to synthesize these particles. Notable amongst these are direct binding of biomolecules or drug on magnetic nano particles, low Curie point functionalized magnetic particles, targeted drug delivery system, photodyne therapy, anti-bacterial activity and bioremediation of marine fungi. Advantages and limitations of these work in light of recent work is also discussed.