Surface Properties of Cleaved Mica

Маслова, М. В.; Герасимова, Л. Г.; Forsling, Willis

doi:10.1023/b:coll.0000030843.30563.c9

Cited by 64 publications

(62 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Substrate, fi lm deposition, and doping : After cleavage in air, the mica sheets were rinsed with deionized water for several minutes to either substitute or neutralize charges that originated from the substrate, e.g., adherent potassium atoms, by dissociated water ions [45][46][47][48] . The substrates were then resistively heated in ultrahigh vacuum (UHV) (250 ° C for about 30 min) to remove adsorbates.…”

Section: Methodsmentioning

confidence: 99%

Alkali Metal Doped Organic Molecules on Insulators: Charge Impact on the Optical Properties

et al. 2010

View full text Add to dashboard Cite

Section: Methodsmentioning

confidence: 99%

Alkali Metal Doped Organic Molecules on Insulators: Charge Impact on the Optical Properties

et al. 2010

View full text Add to dashboard Cite

“…In fact, mica displays a large negative surface charge density in solution, which can form electrostatic bonds with protonated amine groups of aminosilane (Trens et al, 1995). Thus, we can relate the density of the protonated AAPS (i.e., 1.7 × 10 14 molecules.cm -2 ) to the density of negative charges on the bare surface, which is on the order of 1.8 × 10 14 cm -2 (Maslova et al, 2004). Thus, our results clearly indicate that adsorption first proceeds by ionic interaction between the protonated amino groups and the negative charges of the surface until these are neutralized.…”

Section: Effect Of Phmentioning

confidence: 98%

Tapping Mode AFM Imaging for Functionalized Surfaces

Candoni¹

2012

Atomic Force Microscopy Investigations Into Biology - From Cell to Protein

View full text Add to dashboard Cite

“…This may explain why spherulites were not formed on mica. Ion-exchange reactions usually take place on the surface of freshly cleaved mica 25 . Mica is negatively charged and ionic interactions with the ternary amine of SS may occur during the deposition stage promoting interactions between SS molecules and the substrate, preventing spherulite formation 25 .…”

Section: Properties Of the Substratementioning

confidence: 99%

“…Ion-exchange reactions usually take place on the surface of freshly cleaved mica 25 . Mica is negatively charged and ionic interactions with the ternary amine of SS may occur during the deposition stage promoting interactions between SS molecules and the substrate, preventing spherulite formation 25 . The three major components of UG are silicon, boron and sodium oxides, resulting in the relatively low contact angle of this substrate with deionized water and thus the inability of the spherulites to form on such a surface using low SS concentrations 26 .…”

Section: Properties Of the Substratementioning

confidence: 99%

Impact of Substrate Properties on the Formation of Spherulitic Films: A Case Study of Salbutamol Sulfate

Serrano

Mugheirbi

O’Connell

et al. 2016

Crystal Growth & Design

View full text Add to dashboard Cite

Spherulitic assemblies have applications as carriers for drug delivery and as targeting vectors. Presently, the driving force behind the formation of spherulites comprising small drug molecules is not fully understood. Herein, the impact of different substrate types on spherulitic crystallization of salbutamol sulfate (SS) was investigated. Freshly cleaved mica, silicon (111) wafer (SiW), uncoated borosilicate glass (UG), silane coated glass (CG) and stainless steel (MS) were used as substrates. It was demonstrated that the spherulite growth can be controlled via the substrate selection. Spherulite formation was inhibited on hydrophilic substrates, such as mica, possibly due to stronger intermolecular interactions between SS and the substrate than SS-SS interactions. Contact angle measurements established that mica possessed the lowest contact angle (15.1±0.5°) and the values of this parameter increased in the order of UC˂SiW˂CG˂MS. Substrate roughness also played a key role in controlling spherulite formation. SiW, UC and CG had isotropic surfaces with low average roughness, facilitating spherulite formation. Overall, this work demonstrates that it is possible to successfully produce SS spherulites using a single step process at room temperature. Furthermore, the formation of SS spherulites can be tuned by the hydrophobicity of the substrate, an approach that could be applied to assembling spherulites of other small organic molecules. Presently, the driving force behind the formation of spherulites comprising small drug molecules is not fully understood. Herein, the impact of different substrate types on spherulitic crystallization of salbutamol sulfate (SS) was investigated. Freshly cleaved mica, silicon (111) wafer (SiW), uncoated borosilicate glass (UG), silane coated glass (CG) and stainless steel (MS) were used as substrates. It was demonstrated that the spherulite growth can be controlled via the substrate selection. Spherulite formation was inhibited on hydrophilic substrates, such as mica, possibly due to stronger intermolecular interactions between SS and the substrate than SS-SS interactions. Contact angle measurements established that mica possessed the lowest contact angle (15.1±0.5°) and the values of this parameter increased in the order of UC˂SiW˂CG˂MS. Substrate roughness also played a key role in controlling spherulite formation. SiW, UC and CG had isotropic surfaces with low average roughness, facilitating spherulite formation. Overall, this work demonstrates that it is possible to successfully produce SS spherulites using a single step process at room temperature. Furthermore, the formation of SS spherulites can be tuned by the hydrophobicity of the substrate, an approach that could be applied to assembling spherulites of other small organic molecules.

show abstract

Surface Properties of Cleaved Mica

Cited by 64 publications

References 20 publications

Alkali Metal Doped Organic Molecules on Insulators: Charge Impact on the Optical Properties

Alkali Metal Doped Organic Molecules on Insulators: Charge Impact on the Optical Properties

Tapping Mode AFM Imaging for Functionalized Surfaces

Impact of Substrate Properties on the Formation of Spherulitic Films: A Case Study of Salbutamol Sulfate

Contact Info

Product

Resources

About