Near-infrared light-triggered mild-temperature photothermal effect of nanodiamond with functional groups

AbstractGold nanorods have a strong surface plasmon band at the near infrared region. The absorbed light energy is then converted to heat. Since near infrared light can penetrate deeply into tissue, gold nanorods are expected to be used as a contrast agent for bioimaging using the near infrared light and photosensitizers for photothermal therapy. The surface plasmon bands of intravenously injected the gold nanorods were directly monitored from the mouse abdomen by using a spectrophotometer equipped with an integrating sphere. The absorbance at 900 nm from PEG5,000-modified gold nanorods immediately increased after injection and reached a plateau. The injection of phosphatidylcholine-modified gold nanorods also increased the absorbance at 900 nm, but the absorbance decreased single exponentially with a 1.3-min half-life. To demonstrate photothermal tumor therapy, the PEG-modified gold nanorods were directly injected into subcutaneous tumors in mice, then, near infrared laser light was irradiated to the tumor. After the treatment, significant suppression of tumor growth was observed.

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Near-infrared light modulated photothermal effect increases vascular perfusion and enhances polymeric drug delivery

Journal of Controlled Release ◽

10.1016/j.jconrel.2011.06.030 ◽

2011 ◽

Vol 156 (2) ◽

pp. 265-272 ◽

Cited By ~ 55

Author(s):

Marites P. Melancon ◽

Andrew M. Elliott ◽

Anil Shetty ◽

Qian Huang ◽

R. Jason Stafford ◽

...

Keyword(s):

Drug Delivery ◽

Near Infrared ◽

Infrared Light ◽

Photothermal Effect ◽

Vascular Perfusion ◽

Near Infrared Light ◽

Polymeric Drug Delivery ◽

Polymeric Drug

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Near-Infrared Light Triggers Release of Paclitaxel from Biodegradable Microspheres: Photothermal Effect and Enhanced Antitumor Activity

Small ◽

10.1002/smll.201000028 ◽

2010 ◽

Vol 6 (9) ◽

pp. 1022-1031 ◽

Cited By ~ 129

Author(s):

Jian You ◽

Ruping Shao ◽

Xin Wei ◽

Sanjay Gupta ◽

Chun Li

Keyword(s):

Antitumor Activity ◽

Near Infrared ◽

Infrared Light ◽

Photothermal Effect ◽

Biodegradable Microspheres ◽

Near Infrared Light

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Off-on switching of enzyme activity by near-infrared light-induced photothermal phase transition of nanohybrids

Science Advances ◽

10.1126/sciadv.aaw4252 ◽

2019 ◽

Vol 5 (8) ◽

pp. eaaw4252 ◽

Cited By ~ 12

Author(s):

Song Zhang ◽

Changping Wang ◽

Hong Chang ◽

Qiang Zhang ◽

Yiyun Cheng

Keyword(s):

Phase Transition ◽

Enzyme Activity ◽

Near Infrared ◽

Infrared Light ◽

Solution Temperature ◽

Photothermal Effect ◽

Platinum Nanoparticle ◽

Near Infrared Light ◽

Upper Critical Solution Temperature ◽

New Strategy

The off-on manipulation of enzyme activity is a challenging task. We report a new strategy for reversible off-on control of enzyme activity by near-infrared light. Enzymes acting on macromolecular substrates are embedded with an ultrasmall platinum nanoparticle and decorated with thermoresponsive copolymers, which exhibit upper critical solution temperature (UCST) behavior. The polymer-enzyme nanohybrids form microscale aggregates in solution below the UCST to prevent macromolecular substrates from approaching the enzymes and thus inhibit the enzyme activity, and they disassemble above the UCST to reactivate the enzyme. Upon near-infrared irradiation, platinum nanoparticles inside the enzymes generate heat through a photothermal effect to cause phase transition of the copolymers. Therefore, we can reversibly switch off and on the activities of three enzymes acting on polysaccharide, protein, and plasmid. The enzyme activities are increased by up to 61-fold after laser irradiation. This study provides a facile and efficient method for off-on control of enzyme activity.

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