Biomedical Engineering Reference
In-Depth Information
(A)
(B)
FIGURE 2.8
Small instrument for the purification of magnetic NMs: (A) Multitube Magnetic
Separator™ and (B) Supermag Separator™.
From Ocean NanoTech. (For color version of this
figure, the reader is referred to the online version of this topic)
organ targeting, (b) therapeutic molecules for drug delivery, and (c) other mol-
ecules such as small organic dyes for detection and other functions of NP.
2.2.6.3 MNPs Characterization
The characterization of MNPs is similar to those of the AuNPs and QDs. TEM
and gel electrophoresis are used to establish size and size distribution (
Figure 2.9
),
quantitative elemental analysis can be carried out with ICP-AES or with elec-
tron diffraction spectrum (EDS). Magnetic properties are measured with a Lake-
shore 7404 high-sensitivity vibrating sample magnetometer (VSM) with fields
up to 1 T at RT. The hydrodynamic diameter of the particles (core diameter plus
shell thickness) in water is measured using a Malvern Zeta Sizer Nano S-90 DLS
instrument. UV-vis analysis is used to establish concentration. Just like in the
preparation of QDs samples for TEM, the MNP samples are prepared by drying
a hexane dispersion of the particles on amorphous carbon-coated copper grids.
2.3 ORGANIC NM
s
Currently, the most widely used NMs for medical applications are those that
are organic in nature. These include liposomes, micelles, dendrimers, and
