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Are quantum dots ready for in vivo imaging in human subjects?

Cai W, Hsu AR, Li ZB, Chen X - Nanoscale Res Lett (2007)

Bottom Line: Numerous studies on QDs have resulted in major advancements in QD surface modification, coating, biocompatibility, sensitivity, multiplexing, targeting specificity, as well as important findings regarding toxicity and applicability.For in vitro applications, QDs can be used in place of traditional organic fluorescent dyes in virtually any system, outperforming organic dyes in the majority of cases.With new advances in QD technology such as bioluminescence resonance energy transfer, synthesis of smaller size non-Cd based QDs, improved surface coating and conjugation, and multifunctional probes for multimodality imaging, it is likely that human applications of QDs will soon be possible in a clinical setting.

View Article: PubMed Central - PubMed

Affiliation: The Molecular Program at Stanford (MIPS), Department of Radiology and Bio-X Program, Stanford University School of Medicine, 1201 Welch Rd, P095, Stanford, CA 94305-5484, USA.

ABSTRACT
Nanotechnology has the potential to profoundly transform the nature of cancer diagnosis and cancer patient management in the future. Over the past decade, quantum dots (QDs) have become one of the fastest growing areas of research in nanotechnology. QDs are fluorescent semiconductor nanoparticles suitable for multiplexed in vitro and in vivo imaging. Numerous studies on QDs have resulted in major advancements in QD surface modification, coating, biocompatibility, sensitivity, multiplexing, targeting specificity, as well as important findings regarding toxicity and applicability. For in vitro applications, QDs can be used in place of traditional organic fluorescent dyes in virtually any system, outperforming organic dyes in the majority of cases. In vivo targeted tumor imaging with biocompatible QDs has recently become possible in mouse models. With new advances in QD technology such as bioluminescence resonance energy transfer, synthesis of smaller size non-Cd based QDs, improved surface coating and conjugation, and multifunctional probes for multimodality imaging, it is likely that human applications of QDs will soon be possible in a clinical setting.

No MeSH data available.


Related in: MedlinePlus

Different surface coating of QDs results in different in vivo kinetics. mPEG-750 coated QDs circulates much shorter than mPEG-5000 coated QDs. Even at 1 min, significant liver uptake of mPEG-750 QDs is visible. At 1 h, mPEG-750 QDs completely cleared from the circulation while mPEG-5000 QDs persisted. From [151]
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Figure 7: Different surface coating of QDs results in different in vivo kinetics. mPEG-750 coated QDs circulates much shorter than mPEG-5000 coated QDs. Even at 1 min, significant liver uptake of mPEG-750 QDs is visible. At 1 h, mPEG-750 QDs completely cleared from the circulation while mPEG-5000 QDs persisted. From [151]

Mentions: Extensive study of different QD surface coatings revealed important insights for future design of QD-based probes and experimental setups [151,152]. First, QDs are easily visible through the skin of nude mice using NIR QDs. The excitation wavelength is also important in determining how deep QDs may be observed. Second, carboxyl-coated QDs are rapidly taken up by the RES while amino-terminal PEG-coated QDs have varying half-lives in circulation depending on the molecular weight of PEG. Third, when using neutral methoxy-terminated PEG (mPEG) coating, results vary depending on the length of the PEG and the degree of substitution. Highly substituted QDs yielded half-lives in the 3- to 8-h range for mPEG-5000 coated QDs (Fig. 7). Increasing the PEG size to 10 kD or 20 kD produced no further improvement in the circulation half-life. Fourth, sites of deposition vary with the QD surface coating. Amino-PEG, carboxy-PEG, and mPEG-700 coated QDs are all deposited in the RES with sites slightly varying. Deposition of uncharged PEG coated QDs depended on the molecular size of the PEG and on the density of substitution. Most importantly, the injected dose of all types of QDs tested in these studies was excreted in the feces within 1–2 days.


Are quantum dots ready for in vivo imaging in human subjects?

Cai W, Hsu AR, Li ZB, Chen X - Nanoscale Res Lett (2007)

Different surface coating of QDs results in different in vivo kinetics. mPEG-750 coated QDs circulates much shorter than mPEG-5000 coated QDs. Even at 1 min, significant liver uptake of mPEG-750 QDs is visible. At 1 h, mPEG-750 QDs completely cleared from the circulation while mPEG-5000 QDs persisted. From [151]
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3050636&req=5

Figure 7: Different surface coating of QDs results in different in vivo kinetics. mPEG-750 coated QDs circulates much shorter than mPEG-5000 coated QDs. Even at 1 min, significant liver uptake of mPEG-750 QDs is visible. At 1 h, mPEG-750 QDs completely cleared from the circulation while mPEG-5000 QDs persisted. From [151]
Mentions: Extensive study of different QD surface coatings revealed important insights for future design of QD-based probes and experimental setups [151,152]. First, QDs are easily visible through the skin of nude mice using NIR QDs. The excitation wavelength is also important in determining how deep QDs may be observed. Second, carboxyl-coated QDs are rapidly taken up by the RES while amino-terminal PEG-coated QDs have varying half-lives in circulation depending on the molecular weight of PEG. Third, when using neutral methoxy-terminated PEG (mPEG) coating, results vary depending on the length of the PEG and the degree of substitution. Highly substituted QDs yielded half-lives in the 3- to 8-h range for mPEG-5000 coated QDs (Fig. 7). Increasing the PEG size to 10 kD or 20 kD produced no further improvement in the circulation half-life. Fourth, sites of deposition vary with the QD surface coating. Amino-PEG, carboxy-PEG, and mPEG-700 coated QDs are all deposited in the RES with sites slightly varying. Deposition of uncharged PEG coated QDs depended on the molecular size of the PEG and on the density of substitution. Most importantly, the injected dose of all types of QDs tested in these studies was excreted in the feces within 1–2 days.

Bottom Line: Numerous studies on QDs have resulted in major advancements in QD surface modification, coating, biocompatibility, sensitivity, multiplexing, targeting specificity, as well as important findings regarding toxicity and applicability.For in vitro applications, QDs can be used in place of traditional organic fluorescent dyes in virtually any system, outperforming organic dyes in the majority of cases.With new advances in QD technology such as bioluminescence resonance energy transfer, synthesis of smaller size non-Cd based QDs, improved surface coating and conjugation, and multifunctional probes for multimodality imaging, it is likely that human applications of QDs will soon be possible in a clinical setting.

View Article: PubMed Central - PubMed

Affiliation: The Molecular Program at Stanford (MIPS), Department of Radiology and Bio-X Program, Stanford University School of Medicine, 1201 Welch Rd, P095, Stanford, CA 94305-5484, USA.

ABSTRACT
Nanotechnology has the potential to profoundly transform the nature of cancer diagnosis and cancer patient management in the future. Over the past decade, quantum dots (QDs) have become one of the fastest growing areas of research in nanotechnology. QDs are fluorescent semiconductor nanoparticles suitable for multiplexed in vitro and in vivo imaging. Numerous studies on QDs have resulted in major advancements in QD surface modification, coating, biocompatibility, sensitivity, multiplexing, targeting specificity, as well as important findings regarding toxicity and applicability. For in vitro applications, QDs can be used in place of traditional organic fluorescent dyes in virtually any system, outperforming organic dyes in the majority of cases. In vivo targeted tumor imaging with biocompatible QDs has recently become possible in mouse models. With new advances in QD technology such as bioluminescence resonance energy transfer, synthesis of smaller size non-Cd based QDs, improved surface coating and conjugation, and multifunctional probes for multimodality imaging, it is likely that human applications of QDs will soon be possible in a clinical setting.

No MeSH data available.


Related in: MedlinePlus