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Cell Labeling for 19F MRI: New and Improved Approach to Perfluorocarbon Nanoemulsion Design.

Patel SK, Williams J, Janjic JM - Biosensors (Basel) (2013)

Bottom Line: This in turn can decrease efficacy of excess nanoemulsion removal and reliability of the cell labeling in vitro.Further, stressors such as elevated temperature in the presence of cells, and centrifugation, did not affect the nanoemulsion droplet size and polydispersity.Detailed synthetic methodology and in vitro testing for these new PFC nanoemulsions is presented.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA. patels1@duq.edu.

ABSTRACT
This report describes novel perfluorocarbon (PFC) nanoemulsions designed to improve ex vivo cell labeling for 19F magnetic resonance imaging (MRI). 19F MRI is a powerful non-invasive technique for monitoring cells of the immune system in vivo, where cells are labeled ex vivo with PFC nanoemulsions in cell culture. The quality of 19F MRI is directly affected by the quality of ex vivo PFC cell labeling. When co-cultured with cells for longer periods of time, nanoemulsions tend to settle due to high specific weight of PFC oils (1.5-2.0 g/mL). This in turn can decrease efficacy of excess nanoemulsion removal and reliability of the cell labeling in vitro. To solve this problem, novel PFC nanoemulsions are reported which demonstrate lack of sedimentation and high stability under cell labeling conditions. They are monodisperse, have small droplet size (~130 nm) and low polydispersity (<0.15), show a single peak in the 19F nuclear magnetic resonance spectrum at -71.4 ppm and possess high fluorine content. The droplet size and polydispersity remained unchanged after 160 days of follow up at three temperatures (4, 25 and 37 °C). Further, stressors such as elevated temperature in the presence of cells, and centrifugation, did not affect the nanoemulsion droplet size and polydispersity. Detailed synthetic methodology and in vitro testing for these new PFC nanoemulsions is presented.

No MeSH data available.


Related in: MedlinePlus

Droplet diameter of nanoemulsions at different concentrations of Pluronic® surfactants (% w/v). Error bars represent the half width of polydispersity index (PDIw/2).
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biosensors-03-00341-f003: Droplet diameter of nanoemulsions at different concentrations of Pluronic® surfactants (% w/v). Error bars represent the half width of polydispersity index (PDIw/2).

Mentions: Figure 2 shows the schematic of nanoemulsion preparation procedures, sonication and microfluidization. Table 1 shows representative test Formulations S1–S6 prepared with olive oil. The dispersed phase concentration was maintained at 10% w/v while surfactants were screened at 1, 3 and 5% w/v. A 1:1 w/w ratio between surfactants was used for the dual surfactant systems. As shown in Figure 3, both 3% and 5% w/v showed droplet diameter and PDI less than 200 nm and 0.2 respectively for Formulations S1, S2, S5 and S6. Formulation S3 containing L121 and P105 showed phase separation, while Formulation S4 formed a gel during thin film leading to further processing problems. Table 1 shows droplet size (diameter), PDIw/2 and PDI of all formulations prepared at 3% w/v surfactant concentration. Though P105 showed optimum stability, P123/P105 (S6) was selected due to its low hydrophilic-lipophilic balance (HLB) value of 12.25. Average HLB values of P123 and P105 were taken as 9.5 and 15 respectively [30].


Cell Labeling for 19F MRI: New and Improved Approach to Perfluorocarbon Nanoemulsion Design.

Patel SK, Williams J, Janjic JM - Biosensors (Basel) (2013)

Droplet diameter of nanoemulsions at different concentrations of Pluronic® surfactants (% w/v). Error bars represent the half width of polydispersity index (PDIw/2).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4263580&req=5

biosensors-03-00341-f003: Droplet diameter of nanoemulsions at different concentrations of Pluronic® surfactants (% w/v). Error bars represent the half width of polydispersity index (PDIw/2).
Mentions: Figure 2 shows the schematic of nanoemulsion preparation procedures, sonication and microfluidization. Table 1 shows representative test Formulations S1–S6 prepared with olive oil. The dispersed phase concentration was maintained at 10% w/v while surfactants were screened at 1, 3 and 5% w/v. A 1:1 w/w ratio between surfactants was used for the dual surfactant systems. As shown in Figure 3, both 3% and 5% w/v showed droplet diameter and PDI less than 200 nm and 0.2 respectively for Formulations S1, S2, S5 and S6. Formulation S3 containing L121 and P105 showed phase separation, while Formulation S4 formed a gel during thin film leading to further processing problems. Table 1 shows droplet size (diameter), PDIw/2 and PDI of all formulations prepared at 3% w/v surfactant concentration. Though P105 showed optimum stability, P123/P105 (S6) was selected due to its low hydrophilic-lipophilic balance (HLB) value of 12.25. Average HLB values of P123 and P105 were taken as 9.5 and 15 respectively [30].

Bottom Line: This in turn can decrease efficacy of excess nanoemulsion removal and reliability of the cell labeling in vitro.Further, stressors such as elevated temperature in the presence of cells, and centrifugation, did not affect the nanoemulsion droplet size and polydispersity.Detailed synthetic methodology and in vitro testing for these new PFC nanoemulsions is presented.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA. patels1@duq.edu.

ABSTRACT
This report describes novel perfluorocarbon (PFC) nanoemulsions designed to improve ex vivo cell labeling for 19F magnetic resonance imaging (MRI). 19F MRI is a powerful non-invasive technique for monitoring cells of the immune system in vivo, where cells are labeled ex vivo with PFC nanoemulsions in cell culture. The quality of 19F MRI is directly affected by the quality of ex vivo PFC cell labeling. When co-cultured with cells for longer periods of time, nanoemulsions tend to settle due to high specific weight of PFC oils (1.5-2.0 g/mL). This in turn can decrease efficacy of excess nanoemulsion removal and reliability of the cell labeling in vitro. To solve this problem, novel PFC nanoemulsions are reported which demonstrate lack of sedimentation and high stability under cell labeling conditions. They are monodisperse, have small droplet size (~130 nm) and low polydispersity (<0.15), show a single peak in the 19F nuclear magnetic resonance spectrum at -71.4 ppm and possess high fluorine content. The droplet size and polydispersity remained unchanged after 160 days of follow up at three temperatures (4, 25 and 37 °C). Further, stressors such as elevated temperature in the presence of cells, and centrifugation, did not affect the nanoemulsion droplet size and polydispersity. Detailed synthetic methodology and in vitro testing for these new PFC nanoemulsions is presented.

No MeSH data available.


Related in: MedlinePlus