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Nonlinear photoacoustic signal amplification from single targets in absorption background.

Sarimollaoglu M, Nedosekin DA, Menyaev YA, Juratli MA, Zharov VP - Photoacoustics (2014)

Bottom Line: This approach was demonstrated by using nonlinear PA flow cytometry platform for label-free detection of circulating melanoma cells in blood background in vitro and in vivo.Nonlinearly amplified PA signals from overheated melanin nanoclusters in melanoma cells became detectable above still linear blood background.Nonlinear nanobubble-based photoacoustics provide new opportunities to significantly (5-20-fold) increase PA contrast of single nanoparticles, cells, viruses and bacteria in complex biological environments.

View Article: PubMed Central - PubMed

Affiliation: Phillips Classic Laser and Nanomedicine Laboratories, Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR USA 72205.

ABSTRACT
Photoacoustic (PA) detection of single absorbing targets such as nanoparticles or cells can be limited by absorption background. We show here that this problem can be overcome by using the nonlinear photoacoustics based on the differences in PA signal dependences on the laser energy from targets and background. Among different nonlinear phenomena, we focused on laser generation of nanobubbles as more efficient PA signal amplifiers from strongly absorbing, highly localized targets in the presence of spatially homogenous absorption background generating linear signals only. This approach was demonstrated by using nonlinear PA flow cytometry platform for label-free detection of circulating melanoma cells in blood background in vitro and in vivo. Nonlinearly amplified PA signals from overheated melanin nanoclusters in melanoma cells became detectable above still linear blood background. Nonlinear nanobubble-based photoacoustics provide new opportunities to significantly (5-20-fold) increase PA contrast of single nanoparticles, cells, viruses and bacteria in complex biological environments.

No MeSH data available.


Related in: MedlinePlus

PA signal traces and rates of melanoma cells in flow at various laser energy fluences. (a) Cells in PBS and (b) mouse blood spiked with cells in artificial flow. (c) PA monitoring of a 50-μm vessel in mouse ear after injection of melanoma cells. (d) Peak rate in flow as function of laser energy fluence. Rates were normalized to the rate at the highest fluence applied. Averaging was 10.
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fig0035: PA signal traces and rates of melanoma cells in flow at various laser energy fluences. (a) Cells in PBS and (b) mouse blood spiked with cells in artificial flow. (c) PA monitoring of a 50-μm vessel in mouse ear after injection of melanoma cells. (d) Peak rate in flow as function of laser energy fluence. Rates were normalized to the rate at the highest fluence applied. Averaging was 10.

Mentions: The study was first performed in artificial flow using 100 μm × 100 μm sized quartz tube to mimic small blood vessels. The flow velocity was set to 5 mm/s. When PBS was run through the tube as control, no PA signals were detected at various laser energy fluences applied. Then melanoma cells in PBS were diluted to achieve concentration of 1 cell per irradiation volume, in order to minimize the possibility of multiple cells passing the laser beam at the same time. PAFC was performed at the same set of laser energy fluences used in the study of static cells, for 5 min each. Snippets of the PAFC traces are shown in Fig. 7a. Peak rates (number of detected cells per minute) were averaged over the 5 min duration and normalized to the rate where highest fluence applied (Fig. 7d). After cleaning the tubes using alcohol, the same procedure repeated using blood (as control) and blood spiked with melanoma cells at the same concentration of 1 cell per irradiation volume (Fig. 7b and d). Although the peak rates differed for cells in PBS and blood at the same energy fluence, normalized rates revealed a similar nonlinear trend (Fig. 7d) as in the static conditions.


Nonlinear photoacoustic signal amplification from single targets in absorption background.

Sarimollaoglu M, Nedosekin DA, Menyaev YA, Juratli MA, Zharov VP - Photoacoustics (2014)

PA signal traces and rates of melanoma cells in flow at various laser energy fluences. (a) Cells in PBS and (b) mouse blood spiked with cells in artificial flow. (c) PA monitoring of a 50-μm vessel in mouse ear after injection of melanoma cells. (d) Peak rate in flow as function of laser energy fluence. Rates were normalized to the rate at the highest fluence applied. Averaging was 10.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4048727&req=5

fig0035: PA signal traces and rates of melanoma cells in flow at various laser energy fluences. (a) Cells in PBS and (b) mouse blood spiked with cells in artificial flow. (c) PA monitoring of a 50-μm vessel in mouse ear after injection of melanoma cells. (d) Peak rate in flow as function of laser energy fluence. Rates were normalized to the rate at the highest fluence applied. Averaging was 10.
Mentions: The study was first performed in artificial flow using 100 μm × 100 μm sized quartz tube to mimic small blood vessels. The flow velocity was set to 5 mm/s. When PBS was run through the tube as control, no PA signals were detected at various laser energy fluences applied. Then melanoma cells in PBS were diluted to achieve concentration of 1 cell per irradiation volume, in order to minimize the possibility of multiple cells passing the laser beam at the same time. PAFC was performed at the same set of laser energy fluences used in the study of static cells, for 5 min each. Snippets of the PAFC traces are shown in Fig. 7a. Peak rates (number of detected cells per minute) were averaged over the 5 min duration and normalized to the rate where highest fluence applied (Fig. 7d). After cleaning the tubes using alcohol, the same procedure repeated using blood (as control) and blood spiked with melanoma cells at the same concentration of 1 cell per irradiation volume (Fig. 7b and d). Although the peak rates differed for cells in PBS and blood at the same energy fluence, normalized rates revealed a similar nonlinear trend (Fig. 7d) as in the static conditions.

Bottom Line: This approach was demonstrated by using nonlinear PA flow cytometry platform for label-free detection of circulating melanoma cells in blood background in vitro and in vivo.Nonlinearly amplified PA signals from overheated melanin nanoclusters in melanoma cells became detectable above still linear blood background.Nonlinear nanobubble-based photoacoustics provide new opportunities to significantly (5-20-fold) increase PA contrast of single nanoparticles, cells, viruses and bacteria in complex biological environments.

View Article: PubMed Central - PubMed

Affiliation: Phillips Classic Laser and Nanomedicine Laboratories, Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR USA 72205.

ABSTRACT
Photoacoustic (PA) detection of single absorbing targets such as nanoparticles or cells can be limited by absorption background. We show here that this problem can be overcome by using the nonlinear photoacoustics based on the differences in PA signal dependences on the laser energy from targets and background. Among different nonlinear phenomena, we focused on laser generation of nanobubbles as more efficient PA signal amplifiers from strongly absorbing, highly localized targets in the presence of spatially homogenous absorption background generating linear signals only. This approach was demonstrated by using nonlinear PA flow cytometry platform for label-free detection of circulating melanoma cells in blood background in vitro and in vivo. Nonlinearly amplified PA signals from overheated melanin nanoclusters in melanoma cells became detectable above still linear blood background. Nonlinear nanobubble-based photoacoustics provide new opportunities to significantly (5-20-fold) increase PA contrast of single nanoparticles, cells, viruses and bacteria in complex biological environments.

No MeSH data available.


Related in: MedlinePlus