Porous silicon membrane for investigation of transmembrane proteins

Tantawi, Khalid; Berdiev, Bakhrom K.; Cerro, Ramón L.; Williams, John D.

doi:10.1016/j.spmi.2013.02.014

Cited by 22 publications

(22 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The membrane capacitance of 0.71 ± 0.053, 0.65 ± 0.034, and 0.61 ± 0.011 μF/cm 2 was obtained after fitting data for 50, 60, and 70 °C respectively, as shown in Figure 4 B. This data is consistent with lipid membranes produced on ordered porous silicon membrane (0.7 ± 0.3 μF/cm 2 ) [ 33 ], nonordered porous silicon membrane (0.63 μF/cm 2 ) [ 34 , 35 ], ordered porous alumina (0.65 ± 0.2 μF/cm 2 ) [ 36 ], and porous silicon nitride (0.40 μF/cm 2 ) [ 37 ]. The capacitance obtained in this work is in agreement with those obtained for the closely related phospholipid phosphatidylcholine membrane in a 1 mM NaCl electrolyte and was reported to be ~0.62 μF/cm 2 [ 38 , 39 ].…”

Section: Resultssupporting

confidence: 77%

Lipid Bilayer Membrane in a Silicon Based Micron Sized Cavity Accessed by Atomic Force Microscopy and Electrochemical Impedance Spectroscopy

et al. 2017

View full text Add to dashboard Cite

Supported lipid bilayers (SLBs) are widely used in biophysical research to probe the functionality of biological membranes and to provide diagnoses in high throughput drug screening. Formation of SLBs at below phase transition temperature (Tm) has applications in nano-medicine research where low temperature profiles are required. Herein, we report the successful production of SLBs at above—as well as below—the Tm of the lipids in an anisotropically etched, silicon-based micro-cavity. The Si-based cavity walls exhibit controlled temperature which assist in the quick and stable formation of lipid bilayer membranes. Fusion of large unilamellar vesicles was monitored in real time in an aqueous environment inside the Si cavity using atomic force microscopy (AFM), and the lateral organization of the lipid molecules was characterized until the formation of the SLBs. The stability of SLBs produced was also characterized by recording the electrical resistance and the capacitance using electrochemical impedance spectroscopy (EIS). Analysis was done in the frequency regime of 10−2–105 Hz at a signal voltage of 100 mV and giga-ohm sealed impedance was obtained continuously over four days. Finally, the cantilever tip in AFM was utilized to estimate the bilayer thickness and to calculate the rupture force at the interface of the tip and the SLB. We anticipate that a silicon-based, micron-sized cavity has the potential to produce highly-stable SLBs below their Tm. The membranes inside the Si cavity could last for several days and allow robust characterization using AFM or EIS. This could be an excellent platform for nanomedicine experiments that require low operating temperatures.

show abstract

Section: Resultssupporting

confidence: 77%

Lipid Bilayer Membrane in a Silicon Based Micron Sized Cavity Accessed by Atomic Force Microscopy and Electrochemical Impedance Spectroscopy

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The considerably higher mobile fraction for monolayer deposition created lipid sesquilayer, 0.76 ± 0.06, demonstrated that the controlled deposition of LB facilitates formation of a supported lipid structure with less defects as observed from prior studies. [57][58] The similar values for fluorescence intensities and nearly identical results for lipid diffusion suggest that a lipid sesquilayer is the structure that forms on EG for vesicle fusion samples. Since FRAP relies on fluorescence intensities and photobleaching to extract parameters for lipid diffusion, we propose that the lipid monolayer on EG was not directly involved in the diffusion coefficient and mobile fraction previously obtained from Raman-FRAP experiments of vesicle fusion samples.…”

Section: Langmuir-blodgett Technique For Lipid Monolayer Deposition Omentioning

confidence: 57%

Characterization of the Lipid Structure and Fluidity of Lipid Membranes on Epitaxial Graphene and Their Correlation to Graphene Features

et al. 2019

View full text Add to dashboard Cite

Graphene has been recognized as an enhanced platform for biosensors due to its high electron mobility. To integrate active membrane proteins into graphene-based materials for such applications, graphene's surface must be functionalized with lipids to mimic the biological environment of these proteins. Several studies have examined supported lipids on various types of graphene and obtained conflicting results for lipid structure. Here, we present a correlative characterization technique based on fluorescence measurements in a Raman spectroscopy setup to study lipid structure and dynamics on epitaxial graphene. Compared to other graphene variations, epitaxial graphene is grown on a substrate more conducive to production of electronics and offers unique topographic features. Based on experimental and computational results, we propose that a lipid sesquilayer (1.5 bilayer) forms on epitaxial graphene and demonstrate that the distinct surface features of epitaxial graphene affect structure and diffusion of supported lipids.

show abstract

“…Among the various porous materials, porous silicon (PSi) has been considered as a favorable material for constructing low-cost label-free optical biosensors due to the easy manipulation of its pore sizes, optical properties, and surface chemistries [ 35 – 37 ]. PSi membranes have been previously used to separate molecules [ 25 , 38 ], construct fuel cells [ 39 , 40 ], and investigate transmembrane proteins [ 41 ]. Open-ended PSi membranes have been fabricated by methods including anodization to etch thinned areas of silicon wafers (“etch-through” approach) [ 39 – 41 ] and electropolishing to separate an anodized PSi film from the substrate (“lift-off” approach) [ 19 , 26 , 42 ].…”

Section: Introductionmentioning

confidence: 99%

“…PSi membranes have been previously used to separate molecules [ 25 , 38 ], construct fuel cells [ 39 , 40 ], and investigate transmembrane proteins [ 41 ]. Open-ended PSi membranes have been fabricated by methods including anodization to etch thinned areas of silicon wafers (“etch-through” approach) [ 39 – 41 ] and electropolishing to separate an anodized PSi film from the substrate (“lift-off” approach) [ 19 , 26 , 42 ]. Challenges in these fabrication approaches arise for the formation of robust and high-quality multilayer optical structures.…”

Section: Introductionmentioning

confidence: 99%

Comparative Kinetic Analysis of Closed-Ended and Open-Ended Porous Sensors

et al. 2016

View full text Add to dashboard Cite

Efficient mass transport through porous networks is essential for achieving rapid response times in sensing applications utilizing porous materials. In this work, we show that open-ended porous membranes can overcome diffusion challenges experienced by closed-ended porous materials in a microfluidic environment. A theoretical model including both transport and reaction kinetics is employed to study the influence of flow velocity, bulk analyte concentration, analyte diffusivity, and adsorption rate on the performance of open-ended and closed-ended porous sensors integrated with flow cells. The analysis shows that open-ended pores enable analyte flow through the pores and greatly reduce the response time and analyte consumption for detecting large molecules with slow diffusivities compared with closed-ended pores for which analytes largely flow over the pores. Experimental confirmation of the results was carried out with open- and closed-ended porous silicon (PSi) microcavities fabricated in flow-through and flow-over sensor configurations, respectively. The adsorption behavior of small analytes onto the inner surfaces of closed-ended and open-ended PSi membrane microcavities was similar. However, for large analytes, PSi membranes in a flow-through scheme showed significant improvement in response times due to more efficient convective transport of analytes. The experimental results and theoretical analysis provide quantitative estimates of the benefits offered by open-ended porous membranes for different analyte systems.

show abstract

Porous silicon membrane for investigation of transmembrane proteins

Cited by 22 publications

References 28 publications

Lipid Bilayer Membrane in a Silicon Based Micron Sized Cavity Accessed by Atomic Force Microscopy and Electrochemical Impedance Spectroscopy

Lipid Bilayer Membrane in a Silicon Based Micron Sized Cavity Accessed by Atomic Force Microscopy and Electrochemical Impedance Spectroscopy

Characterization of the Lipid Structure and Fluidity of Lipid Membranes on Epitaxial Graphene and Their Correlation to Graphene Features

Comparative Kinetic Analysis of Closed-Ended and Open-Ended Porous Sensors

Contact Info

Product

Resources

About