Porphyrin Shell Microbubbles with Intrinsic Ultrasound and Photoacoustic Properties

 
Porphyrin–phospholipid conjugates were used to create photonic microbubbles (MBs) having a porphyrin shell (“porshe”), and their acoustic and photoacoustic properties were investigated. The inclusion of porphyrin–lipid in the MB shell increased the yield, improved the serum stability, and generated a narrow volumetric size distribution with a peak size of 2.7 ± 0.2 μm. Using an acoustic model, we calculated the porshe stiffness to be 3–5 times greater than that of commercial lipid MBs. Porshe MBs were found to be intrinsically suitable for both ultrasound and photoacoustic imaging with a resonance frequency of 9–10 MHz. The distinctive properties of porshe MBs make them potentially advantageous for a broad range of biomedical imaging and therapeutic applications.