|
|
|
|
LEADER |
01000naa a22002652 4500 |
001 |
NLM168412837 |
003 |
DE-627 |
005 |
20231223115045.0 |
007 |
tu |
008 |
231223s2007 xx ||||| 00| ||eng c |
028 |
5 |
2 |
|a pubmed24n0561.xml
|
035 |
|
|
|a (DE-627)NLM168412837
|
035 |
|
|
|a (NLM)17300209
|
040 |
|
|
|a DE-627
|b ger
|c DE-627
|e rakwb
|
041 |
|
|
|a eng
|
100 |
1 |
|
|a Finnie, Kim S
|e verfasserin
|4 aut
|
245 |
1 |
0 |
|a Formation of silica nanoparticles in microemulsions
|
264 |
|
1 |
|c 2007
|
336 |
|
|
|a Text
|b txt
|2 rdacontent
|
337 |
|
|
|a ohne Hilfsmittel zu benutzen
|b n
|2 rdamedia
|
338 |
|
|
|a Band
|b nc
|2 rdacarrier
|
500 |
|
|
|a Date Completed 06.07.2007
|
500 |
|
|
|a Date Revised 21.11.2013
|
500 |
|
|
|a published: Print-Electronic
|
500 |
|
|
|a Citation Status MEDLINE
|
520 |
|
|
|a Silica nanoparticles for controlled release applications have been produced by the reaction of tetramethylorthosilicate (TMOS) inside the water droplets of a water-in-oil microemulsion, under both acidic (pH 1.05) and basic (pH 10.85) conditions. In-situ FTIR measurements show that the addition of TMOS to the microemulsion results in the formation of silica as TMOS, preferentially located in the oil phase, diffuses into the water droplets. Once in the hydrophilic domain, hydrolysis occurs rapidly as a result of the high local concentration of water. Varying the pH of the water droplets from 1.05 to 10.85, however, considerably slows the hydrolysis reaction of TMOS. The formation of a dense silica network occurs rapidly under basic conditions, with IR indicating the slower formation of more disordered silica in acid. SAXS analysis of the evolving particles shows that approximately 11 nm spheres are formed under basic conditions; these are stabilized by a water/surfactant layer on the particle surface during formation. Under acidic conditions, highly uniform approximately 5 nm spheres are formed, which appear to be retained within the water droplets (approximately 6 nm diameter) and form an ordered micelle nanoparticle structure that exhibits sufficient longer-range order to generate a peak in the scattering at q approximately equal to 0.05 A-1. Nitrogen adsorption analysis reveals that high surface area (510 m2/g) particles with an average pore size of 1 nm are formed at pH 1.05. In contrast, base synthesis results in low surface area particles with negligible internal porosity
|
650 |
|
4 |
|a Journal Article
|
650 |
|
7 |
|a Emulsions
|2 NLM
|
650 |
|
7 |
|a Micelles
|2 NLM
|
650 |
|
7 |
|a Water
|2 NLM
|
650 |
|
7 |
|a 059QF0KO0R
|2 NLM
|
650 |
|
7 |
|a Silicon Dioxide
|2 NLM
|
650 |
|
7 |
|a 7631-86-9
|2 NLM
|
650 |
|
7 |
|a Nitrogen
|2 NLM
|
650 |
|
7 |
|a N762921K75
|2 NLM
|
700 |
1 |
|
|a Bartlett, John R
|e verfasserin
|4 aut
|
700 |
1 |
|
|a Barbé, Christophe J A
|e verfasserin
|4 aut
|
700 |
1 |
|
|a Kong, Linggen
|e verfasserin
|4 aut
|
773 |
0 |
8 |
|i Enthalten in
|t Langmuir : the ACS journal of surfaces and colloids
|d 1992
|g 23(2007), 6 vom: 13. März, Seite 3017-24
|w (DE-627)NLM098181009
|x 1520-5827
|7 nnns
|
773 |
1 |
8 |
|g volume:23
|g year:2007
|g number:6
|g day:13
|g month:03
|g pages:3017-24
|
912 |
|
|
|a GBV_USEFLAG_A
|
912 |
|
|
|a SYSFLAG_A
|
912 |
|
|
|a GBV_NLM
|
912 |
|
|
|a GBV_ILN_22
|
912 |
|
|
|a GBV_ILN_350
|
912 |
|
|
|a GBV_ILN_721
|
951 |
|
|
|a AR
|
952 |
|
|
|d 23
|j 2007
|e 6
|b 13
|c 03
|h 3017-24
|