Spatial light modulators have become an essential tool for advanced microscopy, enabling breakthroughs in 3D, phase, and super-resolution imaging. However, continuous spatial-light modulation that is capable of capturing sub-millisecond microscopic motion without diffraction artifacts and polarization dependence is challenging. Here we present a photothermal spatial light modulator (PT-SLM) enabling fast phase imaging for nanoscopic 3D reconstruction. The PT-SLM can generate a step-like wavefront change, free of diffraction artifacts, with a high transmittance and a modulation efficiency independent of light polarization. We achieve a phase-shift > π and a response time as short as 70 µs with a theoretical limit in the sub microsecond range. We used the PT-SLM to perform quantitative phase imaging of sub-diffractional species to decipher the 3D nanoscopic displacement of microtubules and study the trajectory of a diffusive microtubule-associated protein, providing insights into the mechanism of protein navigation through a complex microtubule network.
- MeSH
- časové faktory MeSH
- interferenční mikroskopie metody statistika a číselné údaje MeSH
- kovové nanočástice ultrastruktura MeSH
- lidé MeSH
- mikroskopie atomárních sil MeSH
- mikroskopie fázově kontrastní metody statistika a číselné údaje MeSH
- mikrotubuly metabolismus ultrastruktura MeSH
- nanotechnologie MeSH
- nanotrubičky ultrastruktura MeSH
- optické jevy MeSH
- počítačová simulace MeSH
- proteiny asociované s mikrotubuly metabolismus MeSH
- proteiny buněčného cyklu metabolismus MeSH
- Schizosaccharomyces pombe - proteiny metabolismus MeSH
- světlo MeSH
- tubulin metabolismus MeSH
- zlato MeSH
- zobrazování trojrozměrné metody statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
We report a novel approach to biosensor-based observations of biomolecular interactions which enables real-time monitoring of biomolecular interactions in complex media. This approach is demonstrated by investigating the interaction between the human chorionic gonadotropin (hCG) and its antibody in blood plasma using a surface plasmon resonance biosensor and a dispersionless microfluidics system. The real-time binding data obtained in blood plasma are compared with those obtained in buffer and blood plasma using a conventional method. It is also demonstrated that the proposed approach can enhance the capability of the biosensor to detect biomolecules in complex samples in terms of detection time and sensitivity. In the model experiment, this approach is shown to enable direct detection of hCG in blood plasma at levels which are five times lower than those detected using the conventional detection approach.
- MeSH
- biosenzitivní techniky metody MeSH
- choriogonadotropin krev chemie MeSH
- lidé MeSH
- mikrofluidika MeSH
- povrchová plasmonová rezonance metody MeSH
- protilátky chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Surface plasmon resonance (SPR) biosensor for high-throughput screening of protein biomarkers in diluted blood plasma is reported. The biosensor combines a high-resolution SPR imaging sensor and a high-density protein array with low-fouling background. The SPR imaging sensor utilizes polarization contrast and advanced referencing and provides a total of 120 sensing areas (each 200 μm×150 μm). Antibodies are immobilized on the sensing areas via hybridization of antibody-oligonucleotide conjugates to thiolated complementary oligonucleotides microspotted on the sensor surface (DNA-directed immobilization). A low-fouling background is achieved by covalent immobilization of bovine serum albumin to carboxyl-terminated thiols filling the areas among the thiolated oligonucleotides and outside the sensing areas. The biosensor was evaluated for detection of protein biomarkers relevant to cancer diagnostics--human chorionic gonadotropin (hCG) and activated leukocyte cell adhesion molecule (ALCAM) both in buffer and in 10% blood plasma. Limits of detection as low as 45 ng/mL (ALCAM) and 100 ng/mL (hCG) were achieved in blood plasma samples.
- MeSH
- biologické markery krev MeSH
- CD antigeny krev MeSH
- choriogonadotropin krev MeSH
- design vybavení MeSH
- fetální proteiny MeSH
- imobilizační protilátky MeSH
- imobilizované proteiny MeSH
- krevní proteiny analýza MeSH
- lidé MeSH
- limita detekce MeSH
- molekuly buněčné adheze neuronové krev MeSH
- nádorové biomarkery krev MeSH
- nádory krev diagnóza MeSH
- oligonukleotidy MeSH
- povrchová plasmonová rezonance přístrojové vybavení metody statistika a číselné údaje MeSH
- refraktometrie MeSH
- sérový albumin hovězí MeSH
- skot MeSH
- thionukleotidy MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
We present a compact surface plasmon resonance (SPR) biosensor for the detection of bisphenol A (BpA), an endocrine-disrupting chemical. The biosensor is based on an SPR sensor platform (SPRCD) and the binding inhibition detection format. The detection of BpA in PBS and wastewater was performed at concentrations ranging from 0.05 to 1,000 ng/ml. The limit of detection for BpA in PBS and wastewater was estimated to be 0.08 and 0.14 ng/ml, respectively. It was also demonstrated that the biosensor can be regenerated for repeated use. Results achieved with the SPR biosensor are compared with those obtained using ELISA and HPLC methods.
High-throughput surface plasmon resonance (SPR) biosensor for rapid and parallelized detection of nucleic acids identifying specific bacterial pathogens is reported. The biosensor consists of a high-performance SPR imaging sensor with polarization contrast and internal referencing (refractive index resolution 2 x 10(-7) RIU) and an array of DNA probes microspotted on the surface of the SPR sensor. It is demonstrated that short sequences of nucleic acids (20-23 bases) characteristic for bacterial pathogens such as Brucella abortus, Escherichia coli, and Staphylococcus aureus can be detected at 100 pM levels. Detection of specific DNA or RNA sequences can be performed in less than 15 min by the reported SPR sensor.
- MeSH
- aerobní bakterie genetika izolace a purifikace MeSH
- analýza potravin metody MeSH
- analýza selhání vybavení MeSH
- biosenzitivní techniky metody přístrojové vybavení MeSH
- design vybavení MeSH
- DNA bakterií analýza genetika MeSH
- financování organizované MeSH
- kontaminace potravin analýza MeSH
- potravinářská mikrobiologie MeSH
- povrchová plasmonová rezonance metody přístrojové vybavení MeSH
- reprodukovatelnost výsledků MeSH
- sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů přístrojové vybavení MeSH
- senzitivita a specificita MeSH
- Publikační typ
- hodnotící studie MeSH
This paper describes the direct label-free detection of antibodies against the Epstein-Barr virus (anti-EBNA) using a surface plasmon resonance (SPR) biosensor. The antibody detection was performed using the immunoreaction between anti-EBNA and a respective synthetic peptide (EBNA-1), which was conjugated with bovine serum albumin (BSA-EBNA) and immobilized on the sensor surface. Three immobilization chemistries for the attachment of BSA-EBNA were investigated to optimize ligand density and minimize loss of EBNA-1 immunoreactivity. The developed SPR biosensor functionalized with the optimal immobilization method was calibrated and characterized in terms of detection limit, reproducibility, regenerability and storability. It was demonstrated that the sensor is capable of detecting concentrations of anti-EBNA as low as 0.2 ng/ml (approximately 1 pM) both in buffer and 1% human serum and can be stored and regenerated for repeated use.
- MeSH
- analýza selhání vybavení MeSH
- biosenzitivní techniky metody přístrojové vybavení MeSH
- design vybavení MeSH
- financování organizované MeSH
- imunoanalýza metody přístrojové vybavení MeSH
- protilátky analýza imunologie MeSH
- virus Epsteinův-Barrové - jaderné antigeny analýza imunologie MeSH
- virus Epsteinův-Barrové imunologie MeSH
Surface plasmon resonance (SPR) biosensors are affinity sensing devices exploiting a special mode of electromagnetic field-surface plasmon-polariton-to detect the binding of analyte molecules from a liquid sample to biomolecular recognition elements immobilized on the surface of the sensor. In this paper, we review advances of SPR biosensor technology towards detection systems for the simultaneous detection of multiple analytes (multi-analyte detection). In addition, we report application of a recently developed multichannel SPR sensor based on spectroscopy of surface plasmons and wavelength division multiplexing of sensing channels to multi-analyte detection.