@article{MTMT:31142384,
	title = {Multiview microscopy of single cells through microstructure-based indirect optical manipulation},
	url = {https://m2.mtmt.hu/api/publication/31142384},
	author = {Vizsnyiczai, Gaszton and Búzás, András and Aekbote Lakshman Rao, Badri and Fekete, Tamás and Grexa, István and Ormos, Pál and Kelemen, Lóránd},
	doi = {10.1364/BOE.379233},
	journal-iso = {BIOMED OPT EXPRESS},
	journal = {BIOMEDICAL OPTICS EXPRESS},
	volume = {11},
	unique-id = {31142384},
	issn = {2156-7085},
	abstract = {Fluorescent observation of cells generally suffers from the limited axial resolution due to the elongated point spread function of the microscope optics. Consequently, three-dimensional imaging results in axial resolution that is several times worse than the transversal. The optical solutions to this problem usually require complicated optics and extreme spatial stability. A straightforward way to eliminate anisotropic resolution is to fuse images recorded from multiple viewing directions achieved mostly by the mechanical rotation of the entire sample. In the presented approach, multiview imaging of single cells is implemented by rotating them around an axis perpendicular to the optical axis by means of holographic optical tweezers. For this, the cells are indirectly trapped and manipulated with special microtools made with two-photon polymerization. The cell is firmly attached to the microtool and is precisely manipulated with 6 degrees of freedom. The total control over the cells' position allows for its multiview fluorescence imaging from arbitrarily selected directions. The image stacks obtained this way are combined into one 3D image array with a multiview image processing pipeline resulting in isotropic optical resolution that approaches the lateral diffraction limit. The presented tool and manipulation scheme can be readily applied in various microscope platforms.},
	year = {2020},
	eissn = {2156-7085},
	pages = {945-962},
	orcid-numbers = {Vizsnyiczai, Gaszton/0000-0003-3245-3736; Fekete, Tamás/0000-0002-1557-845X; Ormos, Pál/0000-0003-2541-5686; Kelemen, Lóránd/0000-0001-7772-2165}
}

@{MTMT:3283144,
	title = {Complex polymer microtools for on-demand contact-free applications},
	url = {https://m2.mtmt.hu/api/publication/3283144},
	author = {Vizsnyiczai, Gaszton and Aekbote Lakshman Rao, Badri and Búzás, András and Ormos, Pál and Kelemen, Lóránd},
	booktitle = {Light Robotics},
	doi = {10.1016/B978-0-7020-7096-9.00006-9},
	unique-id = {3283144},
	abstract = {In this chapter results on light-activated microstructures are surveyed. A short introduction is given on the preparation and actuation methods that make these applications most versatile. The presented structures are fabricated with two-photon polymerization, a 3D direct laser writing technique. With this technique, 3D objects with practically unlimited complexity can be polymerized with 100 nm feature size. The demonstrated systems exploit radiation pressure, single or multibeam optical tweezing and the combination of the two. We also discuss how the microtools can be functionalized with specific physical, chemical, and biochemical methods. With the appropriate surface treatment, specific tailored interactions between the microtools and the targeted objects can be designed into the system, further enhancing the capabilities of this extended optical manipulation approach. © 2017 Elsevier Ltd All rights reserved.},
	year = {2017},
	pages = {167-191},
	orcid-numbers = {Vizsnyiczai, Gaszton/0000-0003-3245-3736; Ormos, Pál/0000-0003-2541-5686; Kelemen, Lóránd/0000-0001-7772-2165}
}

@article{MTMT:3027725,
	title = {Surface-modified complex SU-8 microstructures for indirect optical manipulation of single cells},
	url = {https://m2.mtmt.hu/api/publication/3027725},
	author = {Aekbote Lakshman Rao, Badri and Fekete, Tamás and Jacak, J and Vizsnyiczai, Gaszton and Ormos, Pál and Kelemen, Lóránd},
	doi = {10.1364/BOE.7.000045},
	journal-iso = {BIOMED OPT EXPRESS},
	journal = {BIOMEDICAL OPTICS EXPRESS},
	volume = {7},
	unique-id = {3027725},
	issn = {2156-7085},
	abstract = {We introduce a method that combines two-photon polymerization (TPP) and surface functionalization to enable the indirect optical manipulation of live cells. TPP-made 3D microstructures were coated specifically with a multilayer of the protein streptavidin and non-specifically with IgG antibody using polyethylene glycol diamine as a linker molecule. Protein density on their surfaces was quantified for various coating methods. The streptavidin-coated structures were shown to attach to biotinated cells reproducibly. We performed basic indirect optical micromanipulation tasks with attached structure-cell couples using complex structures and a multi-focus optical trap. The use of such extended manipulators for indirect optical trapping ensures to keep a safe distance between the trapping beams and the sensitive cell and enables their 6 degrees of freedom actuation. (C)2015 Optical Society of America},
	keywords = {DAMAGE; ESCHERICHIA-COLI; DEPENDENCE; WAVELENGTH; ADSORPTION; FABRICATION; MICROFLUIDIC SYSTEMS; force spectroscopy; TWEEZERS; 2-PHOTON POLYMERIZATION},
	year = {2016},
	eissn = {2156-7085},
	pages = {45-56},
	orcid-numbers = {Fekete, Tamás/0000-0002-1557-845X; Vizsnyiczai, Gaszton/0000-0003-3245-3736; Ormos, Pál/0000-0003-2541-5686; Kelemen, Lóránd/0000-0001-7772-2165}
}

@article{MTMT:3120643,
	title = {High accuracy indirect optical manipulation of live cells with functionalized microtools},
	url = {https://m2.mtmt.hu/api/publication/3120643},
	author = {Vizsnyiczai, Gaszton and Aekbote Lakshman Rao, Badri and Búzás, András and Grexa, István and Ormos, Pál and Kelemen, Lóránd},
	doi = {10.1117/12.2237601},
	journal-iso = {PROCEEDINGS OF SPIE},
	journal = {PROCEEDINGS OF SPIE - THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING},
	volume = {9922},
	unique-id = {3120643},
	issn = {0277-786X},
	abstract = {Optical micro manipulation of live cells has been extensively used to study a wide range of cellular phenomena with relevance in basic research or in diagnostics. The approaches span from manipulation of many cells for high throughput measurement or sorting, to more elaborated studies of intracellular events on trapped single cells when coupled with modern imaging techniques. In case of direct cell trapping the damaging effects of light-cell interaction must be minimized, for instance with the choice of proper laser wavelength. Microbeads have already been used for trapping cells indirectly thereby reducing the irradiation damage and increasing trapping efficiency with their high refractive index contrast. We show here that such intermediate objects can be tailor-made for indirect cell trapping to further increase cell-to-focal spot distance while maintaining their free and fast maneuverability. Carefully designed structures were produced with two-photon polymerization with shapes optimized for effective manipulation and cell attachment. Functionalization of the microstructures is also presented that enables cell attachment to them within a few seconds with strength much higher that the optical forces. Fast cell actuation in 6 degrees of freedom is demonstrated with the outlook to possible applications in cell imaging.},
	year = {2016},
	eissn = {1996-756X},
	orcid-numbers = {Vizsnyiczai, Gaszton/0000-0003-3245-3736; Ormos, Pál/0000-0003-2541-5686; Kelemen, Lóránd/0000-0001-7772-2165}
}

@article{MTMT:2946588,
	title = {Optically Trapped Surface-Enhanced Raman Probes Prepared by Silver Photoreduction to 3D Microstructures},
	url = {https://m2.mtmt.hu/api/publication/2946588},
	author = {Vizsnyiczai, Gaszton and Lestyán, T and Joniova, J and Aekbote Lakshman Rao, Badri and Strejčková, A and Ormos, Pál and Miskovsky, P and Kelemen, Lóránd and Bánó, G},
	doi = {10.1021/acs.langmuir.5b01210},
	journal-iso = {LANGMUIR},
	journal = {LANGMUIR},
	volume = {31},
	unique-id = {2946588},
	issn = {0743-7463},
	abstract = {3D microstructures partially covered by silver nanoparticles have been developed and tested for surface-enhanced Raman spectroscopy (SERS) in combination with optical tweezers. The microstructures made by two-photon polymerization of SU-8 photoresist were manipulated in a dual beam optical trap. The active area of the structures was covered by a SERS-active silver layer using chemically assisted photoreduction from silver nitrate solutions. Silver layers of different grain size distributions were created by changing the photoreduction parameters and characterized by scanning electron microscopy. The structures were tested by measuring the SERS spectra of emodin and hypericin. © 2015 American Chemical Society.},
	keywords = {microstructure; SILVER; scanning electron microscopy; raman spectroscopy; Grain size and shape; Surface enhanced Raman spectroscopy; Photoresists; Optical Tweezers; Grain Size Distribution; Silver nanoparticles; Metallographic microstructure; 3D microstructures; Two photon polymerization; SU-8 photoresist; Trapped surfaces; Silver nitrate solutions},
	year = {2015},
	eissn = {1520-5827},
	pages = {10087-10093},
	orcid-numbers = {Vizsnyiczai, Gaszton/0000-0003-3245-3736; Ormos, Pál/0000-0003-2541-5686; Kelemen, Lóránd/0000-0001-7772-2165}
}

@article{MTMT:3003252,
	title = {Integrated optical biosensor for rapid detection of bacteria},
	url = {https://m2.mtmt.hu/api/publication/3003252},
	author = {Mathesz, Anna and Valkai, Sándor and Újvárosy, Attila and Aekbote Lakshman Rao, Badri and Sipos, Orsolya and Stercz, Balázs and Kocsis, Béla and Szabó, Dóra and Dér, András},
	doi = {10.1515/optof-2015-0002},
	journal-iso = {OPTOFLUID MICROFLUID NANOFLUID},
	journal = {OPTOFLUIDICS MICROFLUIDICS AND NANOFLUIDICS},
	volume = {2},
	unique-id = {3003252},
	abstract = {In medical diagnostics, rapid detection of pathogenic bacteria from body fluids is one of the basic issues. Most state-of-the-art methods require optical labeling, increasing the complexity, duration and cost of the analysis. Therefore, there is a strong need for developing selective sensory devices based on label-free techniques, in order to increase the speed, and reduce the cost of detection. In a recent paper, we have shown that an integrated optical Mach-Zehnder interferometer, a highly sensitive all-optical device made of a cheap photopolymer, can be used as a powerful lab-on-a-chip tool for specific, labelfree detection of proteins. By proper modifications of this technique, our interferometric biosensor was combined with a microfluidic system allowing the rapid and specific detection of bacteria from solutions, having the surface of the sensor functionalized by bacterium-specific antibodies. The experiments proved that the biosensor was able to detect Escherichia coli bacteria at concentrations of 106 cfu/ml within a few minutes, that makes our device an appropriate tool for fast, label-free detection of bacteria from body fluids such as urine or sputum. On the other hand, possible applications of the device may not be restricted to medical microbiology, since bacterial identification is an important task in microbial forensics, criminal investigations, bio-terrorism threats and in environmental studies, as well.},
	year = {2015},
	eissn = {2300-7435},
	pages = {15-21},
	orcid-numbers = {Valkai, Sándor/0000-0001-8479-8141; Stercz, Balázs/0000-0002-9585-8397; Kocsis, Béla/0000-0002-7067-7055; Szabó, Dóra/0000-0002-8601-3923}
}

@mastersthesis{MTMT:3027317,
	title = {Functionalization of polymerized 3D microstructures for biological applications},
	url = {https://m2.mtmt.hu/api/publication/3027317},
	author = {Aekbote Lakshman Rao, Badri},
	doi = {10.14232/phd.2650},
	publisher = {SZTE},
	unique-id = {3027317},
	year = {2015}
}

@article{MTMT:2810059,
	title = {Gold nanoparticle-mediated fluorescence enhancement by two-photon polymerized 3D microstructures},
	url = {https://m2.mtmt.hu/api/publication/2810059},
	author = {Aekbote Lakshman Rao, Badri and Schubert, Félix and Ormos, Pál and Kelemen, Lóránd},
	doi = {10.1016/j.optmat.2014.10.064},
	journal-iso = {OPT MATER},
	journal = {OPTICAL MATERIALS},
	volume = {38},
	unique-id = {2810059},
	issn = {0925-3467},
	abstract = {Fluorescence enhancement achieved by functionalized microstructures made by two-photon polymerization (TPP) is reported for the first time. Microstructures of various shapes made of SU-8 photoresist were prepared and coated with gold nanoparticles (NP) of 80 nm. Localized fluorescence enhancement was demonstrated by microstructures equipped with tips of sub-micron dimensions. The enhancement was realized by positioning the NP-coated structures over fluorescent protein layers. Two fluorophores with their absorption in the red and in the green region of the VIS spectrum were used. Laser scanning confocal microscopy was used to quantify the enhancement. The enhancement factor was as high as 6 in areas of several square-micrometers and more than 3 in the case of local enhancement, comparable with literature values for similar nanoparticles. The structured pattern of the observed fluorescence intensity indicates a classic enhancement mechanism realized by standing waves over reflecting surfaces. With further development mobile microtools made by TPP and functionalized by metal NPs can be actuated by optical tweezers and position to any fluorescent micro-object, such as single cells to realize localized, targeted fluorescence enhancement. (C) 2014 Elsevier B.V. All rights reserved.},
	keywords = {AU; METAL; Mirrors; nanomaterials; Fluorescence enhancement; Surface functionalization; Gold nanoparticle; two-photon polymerization; live cells; INTERFERENCE-CONTRAST MICROSCOPY; Microstructure fabrication},
	year = {2014},
	eissn = {1873-1252},
	pages = {301-309},
	orcid-numbers = {Schubert, Félix/0000-0001-8647-5354; Ormos, Pál/0000-0003-2541-5686; Kelemen, Lóránd/0000-0001-7772-2165}
}

@article{MTMT:2835251,
	title = {Optical tools for localized fluorescence enhancement and single cell studies},
	url = {https://m2.mtmt.hu/api/publication/2835251},
	author = {Aekbote Lakshman Rao, Badri and Kelemen, L and Busaz, A and Ormos, P},
	journal-iso = {EUR BIOPHYS J},
	journal = {EUROPEAN BIOPHYSICS JOURNAL},
	volume = {42},
	unique-id = {2835251},
	issn = {0175-7571},
	year = {2013},
	eissn = {1432-1017},
	pages = {S139-S139}
}

@article{MTMT:2835252,
	title = {Indirect optical manipulation of live cells with functionalized polymer microtools},
	url = {https://m2.mtmt.hu/api/publication/2835252},
	author = {Vizsnyiczai, G and Kelemen, L and Aekbote Lakshman Rao, Badri and Búzás, András and Ormos, P},
	journal-iso = {EUR BIOPHYS J},
	journal = {EUROPEAN BIOPHYSICS JOURNAL},
	volume = {42},
	unique-id = {2835252},
	issn = {0175-7571},
	year = {2013},
	eissn = {1432-1017},
	pages = {S114-S114}
}