4.7 Article

Factors Influencing the Repeated Transient Optical Droplet Vaporization Threshold and Lifetimes of Phase Change, Perfluorocarbon Nanodroplets

Journal

NANOMATERIALS
Volume 13, Issue 15, Pages -

Publisher

MDPI
DOI: 10.3390/nano13152238

Keywords

perfluorocarbon nanodroplets; emulsion; photoacoustic; ultrasound; vaporization; ODV

Ask authors/readers for more resources

This study investigates the vaporization thresholds of PFCnDs (perfluorocarbon nanodroplets) through optical stimulation, and discovers a phenomenon called preconditioning. The impact of surfactants on the vaporization threshold and imaging lifetime is also studied, and a correlation between PFC critical temperatures and vaporization thresholds is observed.
Perfluorocarbon nanodroplets (PFCnDs) are sub-micrometer emulsions composed of a surfactant-encased perfluorocarbon (PFC) liquid and can be formulated to transiently vaporize through optical stimulation. However, the factors governing repeated optical droplet vaporization (ODV) have not been investigated. In this study, we employ high-frame-rate ultrasound (US) to characterize the ODV thresholds of various formulations and imaging parameters and identify those that exhibit low vaporization thresholds and repeatable vaporization. We observe a phenomenon termed preconditioning, where initial laser pulses generate reduced US contrast that appears linked with an increase in nanodroplet size. Variation in laser pulse repetition frequency is found not to change the vaporization threshold, suggesting that preconditioning is not related to residual heat. Surfactants (bovine serum albumin, lipids, and zonyl) impact the vaporization threshold and imaging lifetime, with lipid shells demonstrating the best performance with relatively low thresholds (21.6 & PLUSMN; 3.7 mJ/cm(2)) and long lifetimes (t(1/2) = 104 & PLUSMN; 21.5 pulses at 75 mJ/cm(2)). Physiological stiffness does not affect the ODV threshold and may enhance nanodroplet stability. Furthermore, PFC critical temperatures are found to correlate with vaporization thresholds. These observations enhance our understanding of ODV behavior and pave the way for improved nanodroplet performance in biomedical applications.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available