In this study, a kind of melanin lipid nanovesicle contrast agent (M-lvca) material with good light absorption and melanin doping is proposed. In this contrast material, lipid nanospheres containing melanin are obtained by ether titration. Then, it is prepared by freeze-drying. In the
experimental part, the shape, structure, particle size and absorption spectrum of the material are studied. In vitro agarose gel model, the ultrasound/photoacoustic analysis of the contrast agent is carried out to detect the effect of different concentration of contrast agent on phagocytosis
of cells. In the diagnosis of breast cancer, the enhancement boundary, the distribution of contrast agent, the enhancement shape, the range change after enhancement, and the penetration of blood vessels are detected. The experimental results show that the contrast agent has the characteristics
of microsphere shape, uniform distribution and strong light absorption ability in the wavelength range of 100 nm∼900 nm. In vitro ultrasound imaging/photoacoustic imaging test, the contrast agent has a good imaging ability. With the increase of the concentration, the imaging ability
will be further enhanced. In the diagnosis of breast cancer, there is a significant difference in the indexes related to ultrasound diagnosis of breast cancer after adding M-lvca contrast agent (P < 0.05). Only a few indexes such as enhancement intensity and perfusion defect have
no significant difference (P > 0.05). In this study, the proposed M-lvca material can improve the imaging effect of related indicators in the early diagnosis of breast cancer, which is helpful to improve the accuracy of breast cancer diagnosis.
Comparison between Fluorescence Imaging and Elemental Analysis to Determine Biodistribution of Inorganic Nanoparticles with Strong Light Absorption