Background Factors limiting the efficacy of conventional antiretroviral therapy for HIV-1 infection include treatment adherence, pharmacokinetics and penetration into viral sanctuaries. These affect the rate of viral mutation and drug resistance. In attempts to bypass such limitations, nanoparticles containing ritonavir, indinavir and efavirenz (described as nanoART) were manufactured to assess macrophage-based drug delivery. Methods NanoART were made by high-pressure homogenization of crystalline drug with various surfactants. Size, charge and shape of the nanoparticles were assessed. Monocyte-derived macrophage nanoART uptake, drug release, migration and cytotoxicity were determined. Drug levels were measured by reverse-phase high-performance liquid chromatography. Results Efficient monocyte-derived macrophage cytoplasmic vesicle uptake in less than 30 min based on size, charge and coating was observed. Antiretroviral drugs were released over 14 days and showed dose-dependent reduction in progeny virion production and HIV-1 p24 antigen. Cytotoxicities resulting from nanoART carriage were limited. Conclusion These results support the continued development of macrophage-mediated nanoART carriage for HIV-1 disease.

Micron‐sized monodisperse superparamagnetic polyglycidyl methacrylate (PGMA) particles with functional amino groups were prepared by a process involving: (1) preparation of parent monodisperse PGMA particles by the dispersion polymerization method, (2) chemical modification of the PGMA particles with ethylenediamine (EDA) to yield amino groups, and (3) impregnation of iron ions (Fe2+ and Fe3+) inside the particles and subsequently precipitating them with ammonium hydroxide to form magnetite (Fe3O4) nanoparticles within the polymer particles. The resultant magnetic PGMA particles with amino groups were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X‐ray diffractometry (XRD), and vibrating sample magnetometry (VSM). SEM showed that the magnetic particles had an average size of 2.6 μm and were highly monodisperse. TEM demonstrated that the magnetite nanoparticles distributed evenly within the polymer particles. The existence of amino groups in the magnetic polymer particles was confirmed by FTIR. XRD indicated that the magnetic nanoparticles within the polymer were pure Fe3O4 with a spinel structure. VSM results showed that the magnetic polymer particles were superparamagnetic, and saturation magnetization was found to be 16.3 emu/g. The Fe3O4 content of the magnetic particles was 24.3% based on total weight. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3433–3439, 2005

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A novel and effective protocol for the surface modification and quantitative characterization of magnetic polymeric nanospheres prepared by miniemulsion polymerization is reported. Composite nanospheres consisting of polymer-coated iron oxide nanoparticles were prepared by the miniemulsion polymerization of methyl methacrylate and divinylbenzene in the presence of magnetic fluid. Surface modification reaction of the magnetic polymer with poly(ethylene glycol) (PEG) was employed to obtain a hydrophilic hydroxyl-group-functionalized magnetic nanospheres. An affinity dye, Cibacron blue F3G-A (CB), was then coupled covalently to prepare a magnetic nonporous affinity adsorbent. The morphology and magnetic property of the polymer nanospheres obtained were examined by transmission electron microscopy and a vibrating sample magnetometer. The contents of surface groups modified were quantitatively measured by using diffusive reflectance Fourier transform infrared spectroscopy on the basis of a linear relationship between the intensity ratio of IC-O-C/IC=O and the content of PEG. X-ray photoelectron spectroscopy (XPS) was used to examine the surface of magnetic nanospheres. It was confirmed by the comparison of XPS spectra of both dye-coated and uncoated magnetic nanospheres to which the CB ligand was coupled, and the surface of the PEG-modified nanospheres had an exact 3:7 atomic ratio of sulfur to nitrogen.