Nanostructured porous Si optical biosensors: effect of thermal oxidation on their performance and properties.

The influence of thermal oxidation conditions on the performance of porous Si optical biosensors used for label-free and real-time monitoring of enzymatic activity is studied. We compare three oxidation temperatures (400, 600, and 800 °C) and their effect on the enzyme immobilization efficiency and the intrinsic stability of the resulting oxidized porous Si (PSiO2), Fabry-Pérot thin films. Importantly, we show that the thermal oxidation profoundly affects the biosensing performance in terms of greater optical sensitivity, by monitoring the catalytic activity of horseradish peroxidase and trypsin-immobilized PSiO2. Despite the significant decrease in porous volume and specific surface area (confirmed by nitrogen gas adsorption-desorption studies) with elevating the oxidation temperature, higher content and surface coverage of the immobilized enzymes is attained. This in turn leads to greater optical stability and sensitivity of PSiO2 nanostructures. Specifically, films produced at 800 °C exhibit stable optical readout in aqueous buffers combined with superior biosensing performance. Thus, by proper control of the oxide layer formation, we can eliminate the aging effect, thus achieving efficient immobilization of different biomolecules, optical signal stability, and sensitivity.

[1]  E. Segal,et al.  Advancing nanostructured porous si-based optical transducers for label free bacteria detection. , 2012, Advances in experimental medicine and biology.

[2]  S. Libertino,et al.  Layer uniformity in glucose oxidase immobilization on SiO2 surfaces , 2007 .

[3]  J. Salonen,et al.  Thermal stabilization of porous silicon for biomedical applications , 2014 .

[4]  S. Leppävuori,et al.  Thermal Oxidation of Porous Silicon: Study on Reaction Kinetics , 2004 .

[5]  K. Gaus,et al.  Different functionalization of the internal and external surfaces in mesoporous materials for biosensing applications using "click" chemistry. , 2011, Langmuir : the ACS journal of surfaces and colloids.

[6]  Jun Liu,et al.  Entrapping enzyme in a functionalized nanoporous support. , 2002, Journal of the American Chemical Society.

[7]  Andreas Janshoff,et al.  Macroporous p-Type Silicon Fabry−Perot Layers. Fabrication, Characterization, and Applications in Biosensing , 1998 .

[8]  S. Katoh,et al.  Liposome immunoblotting assay using a substrate‐forming precipitate inside immunoliposomes , 2002, Biotechnology and bioengineering.

[9]  M. Sailor,et al.  Photoluminescence‐Based Sensing With Porous Silicon Films, Microparticles, and Nanoparticles , 2009 .

[10]  S. Libertino,et al.  XPS and AFM characterization of the enzyme glucose oxidase immobilized on SiO(2) surfaces. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[11]  Sabine Szunerits,et al.  Imaging of DNA hybridization on microscopic polypyrrole patterns using scanning electrochemical microscopy (SECM): the HRP bio-catalyzed oxidation of 4-chloro-1-naphthol. , 2006, The Analyst.

[12]  Lisa M. Bonanno,et al.  Nanostructured porous silicon-polymer-based hybrids: from biosensing to drug delivery. , 2011, Nanomedicine.

[13]  N. Voelcker,et al.  Catalyzed Oxidative Corrosion of Porous Silicon Used as an Optical Transducer for Ligand–Receptor Interactions , 2008, Chembiochem : a European journal of chemical biology.

[14]  F. Cunin,et al.  Characterization of phospholipid bilayer formation on a thin film of porous SiO2 by reflective interferometric Fourier transform spectroscopy (RIFTS). , 2012, Langmuir : the ACS journal of surfaces and colloids.

[15]  B. Miller Nano-structured Silicon Optical Sensors , 2010 .

[16]  M. Sailor Porous Silicon in Practice: Preparation, Characterization and Applications , 2012 .

[17]  J. Chao,et al.  Biofunctionalisation of porous silicon (PS) surfaces by using homobifunctional cross-linkers , 2006 .

[18]  M. J. Kim,et al.  Solid-state nanopore detection of protein complexes: applications in healthcare and protein kinetics. , 2013, Small.

[19]  C. Prestidge,et al.  Thermal oxidation for controlling protein interactions with porous silicon. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[20]  M. Maynadier,et al.  Anionic porphyrin-grafted porous silicon nanoparticles for photodynamic therapy. , 2013, Chemical communications.

[21]  Wei-hong Wang,et al.  Immobilized enzyme reactors in HPLC and its application in inhibitor screening: A review , 2011, Journal of pharmaceutical analysis.

[22]  Michael J. Sailor,et al.  Real-time monitoring of enzyme activity in a mesoporous silicon double layer , 2009, Nature nanotechnology.

[23]  Bin Guan,et al.  Protease detection using a porous silicon based Bloch surface wave optical biosensor. , 2010, Optics express.

[24]  U. Wollenberger,et al.  Influence of Modifications on the Efficiency of Pyrolysed CoTMPP as Electrode Material for Horseradish Peroxidase and the Reduction of Hydrogen Peroxide , 2006 .

[25]  Martin J. Sweetman,et al.  Interferometric porous silicon transducers using an enzymatically amplified optical signal , 2011 .

[26]  J. Devoisselle,et al.  Confinement of Thermoresponsive Hydrogels in Nanostructured Porous Silicon Dioxide Templates , 2007 .

[27]  G. Hays,et al.  Identification of genetically and oceanographically distinct blooms of jellyfish , 2013, Journal of The Royal Society Interface.

[28]  E. Segal,et al.  Designing porous silicon-based microparticles as carriers for controlled delivery of mitoxantrone dihydrochloride , 2013 .

[29]  Nicolas H Voelcker,et al.  Porous silicon biosensors on the advance. , 2009, Trends in biotechnology.

[30]  J. Sipe,et al.  Nanoscale porous silicon waveguide for label-free DNA sensing. , 2008, Biosensors & bioelectronics.

[31]  E. Segal,et al.  EFFECT OF THERMAL OXIDATION ON THE PERFORMANCE OF NANOSTRUCTURED POROUS SI OPTICAL BIOSENSORS , 2014 .

[32]  Lisa M. Bonanno,et al.  Tunable detection sensitivity of opiates in urine via a label-free porous silicon competitive inhibition immunosensor. , 2010, Analytical chemistry.

[33]  H. Zou,et al.  Size-selective proteolysis on mesoporous silica-based trypsin nanoreactor for low-MW proteome analysis. , 2010, Chemical communications.

[34]  Chao Liang,et al.  Thin-Layer Polymer Wrapped Enzymes Encapsulated in Hierarchically Mesoporous Silica with High Activity and Enhanced Stability , 2014, Scientific Reports.

[35]  Michael J Sailor,et al.  Biosensing using porous silicon double-layer interferometers: reflective interferometric Fourier transform spectroscopy. , 2005, Journal of the American Chemical Society.

[36]  Mitchel J. Doktycz,et al.  Comparison of techniques for enzyme immobilization on silicon supports , 1999 .

[37]  Conrad C. Huang,et al.  UCSF Chimera—A visualization system for exploratory research and analysis , 2004, J. Comput. Chem..

[38]  Kristopher A Kilian,et al.  The importance of surface chemistry in mesoporous materials: lessons from porous silicon biosensors. , 2009, Chemical communications.

[39]  Ester Segal,et al.  Picking up the pieces: a generic porous Si biosensor for probing the proteolytic products of enzymes. , 2013, Analytical chemistry.

[40]  John T. Yates,et al.  FTIR Study of the Oxidation of Porous Silicon , 1997 .

[41]  Ester Segal,et al.  Engineering nanostructured porous SiO2 surfaces for bacteria detection via "direct cell capture". , 2011, Analytical chemistry.

[42]  Kristopher A Kilian,et al.  Smart tissue culture: in situ monitoring of the activity of protease enzymes secreted from live cells using nanostructured photonic crystals. , 2009, Nano letters.

[43]  Lisa M. Bonanno,et al.  Steric crowding effects on target detection in an affinity biosensor. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[44]  P. Fauchet,et al.  Silicon photonic crystal nanocavity-coupled waveguides for error-corrected optical biosensing. , 2011, Biosensors & bioelectronics.

[45]  A. Hoff,et al.  Evidence that blue luminescence of oxidized porous silicon originates from SiO2 , 1994 .

[46]  A. G. Cullis,et al.  The structural and luminescence properties of porous silicon , 1997 .

[47]  Kristopher A Kilian,et al.  Peptide-modified optical filters for detecting protease activity. , 2007, ACS nano.

[48]  M. Sailor,et al.  Highly stable porous silicon-carbon composites as label-free optical biosensors. , 2012, ACS nano.

[49]  Ying Zhu,et al.  Functionalised porous silicon as a biosensor: emphasis on monitoring cells in vivo and in vitro. , 2013, The Analyst.

[50]  Chumin Wang,et al.  Oxygen Absorption in Free-Standing Porous Silicon: A Structural, Optical and Kinetic Analysis , 2010, Nanoscale research letters.

[51]  U. Pal,et al.  Effects of crystallization and dopant concentration on the emission behavior of TiO2:Eu nanophosphors , 2012, Nanoscale Research Letters.

[52]  Michael J Sailor,et al.  "Smart dust": nanostructured devices in a grain of sand. , 2005, Chemical communications.

[53]  E. Segal,et al.  DNA-directed immobilization of horseradish peroxidase onto porous SiO2 optical transducers , 2012, Nanoscale Research Letters.

[54]  Claudia Pacholski,et al.  Photonic Crystal Sensors Based on Porous Silicon , 2013, Sensors.

[55]  Luca De Stefano,et al.  Aminosilane functionalizations of mesoporous oxidized silicon for oligonucleotide synthesis and detection , 2013, Journal of The Royal Society Interface.

[56]  A. Sa’ar Photoluminescence from silicon nanostructures: The mutual role of quantum confinement and surface chemistry , 2009 .

[57]  E. Wang,et al.  In situ electrochemical scanning tunnelling microscopy investigation of structure for horseradish peroxidase and its electricatalytic property , 1996 .