Orthogonal self-assembly on colloidal gold-platinum nanorods

Advanced Materials

Volumn 11, Issue 12, 1999, Pages 1021-1025

  Martin, Benjamin R ^a   Dermody, Daniel J ^a   Reiss, Brian D ^a   Fang, Mingming ^a   Lyon, L Andrew ^a   Natan, Michael J ^a   Mallouk, Thomas E ^a  

^a PENNSYLVANIA STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALCOHOLS; COLLOIDS; CYANIDES; ELECTROCHEMISTRY; ELECTROPLATING; GOLD; MEMBRANES; MOLECULAR STRUCTURE; PARTICLES (PARTICULATE MATTER); PLATINUM; POROUS MATERIALS; SURFACE CHEMISTRY;

ISOCYANIDE; NANOPARTICLES; NANORODS; SELF-ASSEMBLED MONOLAYERS (SAM); THIOL;

NANOSTRUCTURED MATERIALS;

EID: 0032625830     PISSN: 09359648     EISSN: None     Source Type: Journal    
DOI: 10.1002/(SICI)1521-4095(199908)11:12<1021::AID-ADMA1021>3.0.CO;2-S     Document Type: Article

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38. Rods, suspended in ca. 2 mL hexane, were added to 2 mL of 1 mM 1-butaneisocyanide (BIC, Acros) and allowed to react for 18 h. During this time, the solution was shaken several times. The rods were collected and rinsed by 5 centrifugation/resuspension cycles with hexane, and then 1 cycle with ethanol. The rods were resuspended by sonicating briefly in ethanol. This suspension was added to 2 mL of 1 mM 2-mercaptoethylamine (MEA, Aldrich), and was allowed to react for 18 h. Isocyanide groups were displaced from gold by thiols, but not from platinum. The rods were washed and centrifuged with ethanol five times, then suspended in 10 mL of ethanol and purged with argon for 10 min. 5 mL ethanol containing 20 mg Rhodamine B isothiocyanate (Aldrich) was added, and the solution was stirred for 18 h under a positive pressure of Ar. The rods were rinsed and centrifuged 10 times with ethanol. A drop of the resuspended rods was placed on a quartz microscope slide, blotted with filter paper, and allowed to dry.