TY - JOUR
T1 - Aqueous red-emitting silicon nanoparticles for cellular imaging
T2 - Consequences of protecting against surface passivation by hydroxide and water for stable red emission
AU - Chiu, Sheng Kuei
AU - Manhat, Beth A.
AU - De Benedetti, William J.I.
AU - Brown, Anna L.
AU - Fichter, Katye
AU - Vu, Tania
AU - Eastman, Micah
AU - Jiao, Jun
AU - Goforth, Andrea M.
PY - 2013/1/28
Y1 - 2013/1/28
N2 - Stable, aqueous, red-to-near infrared emission is critical for the use of silicon nanoparticles (Si NPs) in biological fluorescence assays, but such Si NPs have been difficult to attain. We report a synthesis and surface modification strategy that protects Si NPs and preserves red photoluminescence (PL) in water for more than 6 mo. The Si NPs were synthesized via high temperature reaction, liberated from an oxide matrix, and functionalized via hydrosilylation to yield hydrophobic particles. The hydrophobic Si NPs were phase transferred to water using the surfactant cetyltrimethylammonium bromide (CTAB) with retention of red PL. CTAB apparently serves a double role in providing stable, aqueous, red-emitting Si NPs by (i) forming a hydrophobic barrier between the Si NPs and water and (ii) providing aqueous colloidal stability via the polar head group. We demonstrate preservation of the aqueous red emission of these Si NPs in biological media and examine the effects of pH on emission color.
AB - Stable, aqueous, red-to-near infrared emission is critical for the use of silicon nanoparticles (Si NPs) in biological fluorescence assays, but such Si NPs have been difficult to attain. We report a synthesis and surface modification strategy that protects Si NPs and preserves red photoluminescence (PL) in water for more than 6 mo. The Si NPs were synthesized via high temperature reaction, liberated from an oxide matrix, and functionalized via hydrosilylation to yield hydrophobic particles. The hydrophobic Si NPs were phase transferred to water using the surfactant cetyltrimethylammonium bromide (CTAB) with retention of red PL. CTAB apparently serves a double role in providing stable, aqueous, red-emitting Si NPs by (i) forming a hydrophobic barrier between the Si NPs and water and (ii) providing aqueous colloidal stability via the polar head group. We demonstrate preservation of the aqueous red emission of these Si NPs in biological media and examine the effects of pH on emission color.
KW - PMT detector sensitivity
KW - aqueous colloid
KW - cell uptake study
KW - fluorescent imaging agent
KW - red fluorescence
KW - semiconductor nanoparticle
KW - silicon nanoparticle
UR - http://www.scopus.com/inward/record.url?scp=84873866125&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84873866125&partnerID=8YFLogxK
U2 - 10.1557/jmr.2012.377
DO - 10.1557/jmr.2012.377
M3 - Article
AN - SCOPUS:84873866125
SN - 0884-2914
VL - 28
SP - 216
EP - 230
JO - Journal of Materials Research
JF - Journal of Materials Research
IS - 2
ER -