Lipid character characteration for the drug-giving system

Carnell, senior applied scientist at Malvern Instruments, and Mike Kazsuba, technical support manager, discussed the application and effect of nanoparticle tracking and analysis techniques and photoscale techniques in characterization liposomes as drug vectors.
lipids are an important drug-giving vector and have been approved for use in a variety of therapeutic formulations. Lipids are made up of phospholipids, with single or multi-layer structures, hydrophobic inner layers and hydrophobic outer layers, which can be made into particles of different sizes. These particles are biodegradable and largely non-toxic.
most important, it encapsulates both hydrophobic and hydrophobic substances. In addition, by modifying the surface of the lipid body, specific physiological sites can also be targeted for drugation, extending the retention time of the lipid body in the body, and can be used to design diagnostic tools.
, as in other similar studies, the key to applying lipids is to ensure that their physical properties are consistent with their use. For example, how does lipids react when they enter the body? Is the lipid body stable enough to ensure targeting? Is granularity suitable for clinical use, or will it disappear in the blood circulation?Understanding the granularity, concentration, and zeta potential of lipid regimens can help predict its changing trends in organisms, while the molecular relationship between charged lipids and the opposite electrical properties can also be monitored by measuring the zeta potential of the polymers produced by the two.
these factors have a significant impact on the effectiveness of drug transmission, especially when drug formulation researchers believe that a lipid body is suitable for transmission vectors, the above factors should be taken into account. Therefore, an analytical system that provides comprehensive data can be of great benefit to the formulation design process. Nanoparticle tracking and analysis technology and dynamic light scattering technology are two important analytical methods, which provide important information for liposome research.
nanoparticle tracking and analysis technology
nanoparticle tracking analysis technology (NTA) uses laser scattering to test nanoparticles in solutions. Using this analysis method, the researchers were able to observe individual particles and track their Brown motion trajectory, which quickly produces a particle size map of each particle based on a single particle over a short period of time.using a scientific digital camera to capture scattered light from particles in the solution, the instrument software can track the movement of each particle frame by frame.velocity of the particles is related to the radius of sphere equivalent fluid mechanics calculated by the Stokes-Einstein equation. NTA technology can calculate granularity grain by grain, and because of the image fragments as the basis for analysis, users can accurately personalise real-time dynamics.NTA technology allows researchers to observe individual nanoparticles at the same time, so that in addition to the basic particle size analysis, the relative light scattering intensity of each lipid body can be determined. The data results are plotted with measured granularity data to distinguish particles consisting of different refractive index (RI) or material in greater detail.
With this unique capability, researchers can explore whether nanoscale drug delivery vectors, such as liposomes, are encapsulated differently: the refractive index (light scattering capacity) of hollow liposomes may be lower than that of liposomes that contain higher refractive index substances. Such differences allow people to distinguish lipids of similar size. In addition, NTA's single particle detection system makes particle concentration measurement possible.
particle size and zeta potential
the position of lipids and cells in the body is largely determined by the granularity of lipids. Mastering the zeta potential of lipid regimens can help predict changes in lipids in the body. The zetaity of a particle is the total charge that a particle obtains in a particular medium. In the case of
gene
therapy, zeta potential measurements can be used to optimize the ratio of specific lipids to various
DNA
protons to minimize formulation aggregation (Figure 4).Dynamic Light Scattering (DLS) is a relatively mature and widely used liposome charactering technique. In addition, marvin Instruments' Zetasizer Nano system is one of the increasingly popular analytical systems capable of measuring both particle size and zeta level, as zeta levels are also important parameters. In general, the researchers used dynamic light scattering technology to measure particle size and laser Doppler microelectring technology to measure zeta protness.light scattering produced by particle Brown motion is also at the heart of DLS technology. DLS technology measures fluctuations in the intensity of scattered light over time and determines the diffusion coefficient of particles. On this basis, the Stokes-Einstein equation is used to
data
into a particle size distribution.when the zeta level is measured using laser Doppler microelectring technology, an electric field is applied to the molecular solution or particle dispersion, and the particles move at a rate that is related to the zeta level. By measuring this rate, the electrophoresis migration rate can be calculated, and the zeta and zeta map distribution of particles can be calculated accordingly.Conclusion
The physical charactering of liposomes is very important for understanding the suitability of lipids in various applications, and rapid and repeatable charactering is an important consideration in the process of research and development and quality control. The techniques described in this paper can provide additional information such as particle size, concentration, zeta potential, etc. of lipid regimens.