MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last d... more MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last decade. Presently, the need has come to scale down to nanoscale cantilevers for better and faster sensing. Previously, metallic cantilevers were mostly used for biochemical/analyte detection which is more expensive compared to the polymeric ones. Arrays of sensors can be fabricated easily as SU-8 is highly resistant to chemicals. In addition, SU-8 is also biocompatible, making it the most suitable material for biochemical sensors. Furthermore, due to its low Young’s modulus, high sensitivity can be achieved. Polymeric nanocantilevers have been used in this study for detection of BSA (Bovine Serum Albumin) in a short time and low amount of concentration. Deflection was measured and observed through optical beam deflection technique and optical diffraction-based approach using high-speed camera.
An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. ... more An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. Images collected from cancerous patients and normal volunteers have shown a clear difference in fluorescence intensity.
In this study a hand held probe has been automated using a motorized stage and LabVIEW based cont... more In this study a hand held probe has been automated using a motorized stage and LabVIEW based control and acquisition system for in-vitro cervical precancer diagnosis. The stage movement is controlled by two motors for vertical and horizontal movement while a third motor is utilized for changing the polarization state. The data acquisition and storing was thus performed by moving the probe to a specific site, acquiring polarized fluorescence and elastic scattering signals and creating a user friendly graphical user interface(GUI) panel to suit our needs. Another GUI in MATLAB has also been developed for the real time analysis of data captured through the automatic acquisition system. Three windows were created inside the GUI to display calculated intrinsic fluorescence, for statistical analysis and classification. Principal component analysis was applied to extract the features and classification was done by Mahalanobis distance based algorithm. The classification results have been presented of different grades of cervical cancer
Cervical cancer can be treated and cured if diagnosed at an early stage. Optical devices, develop... more Cervical cancer can be treated and cured if diagnosed at an early stage. Optical devices, developed on smartphone-based platforms, are being tested for this purpose as they are cost-effective, robust, and field portable, showing good efficiency compared to the existing commercial devices. This study reports on the applicability of a 3D printed smartphone-based spectroscopic device (3D-SSD) for the early diagnosis of cervical cancer. The proposed device has the ability to evaluate intrinsic fluorescence (IF) from the collected polarized fluorescence (PF) and elastic-scattering (ES) spectra from cervical tissue samples of different grades. IF spectra of 30 cervical tissue samples have been analyzed and classified using a combination of principal component analysis (PCA) and random forest (RF)-based multi-class classification algorithm with an overall accuracy above 90%. The usage of smartphone for image collection, spectral data analysis, and display makes this device a potential cont...
Translational Biophotonics: Diagnostics and Therapeutics
An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. ... more An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. Images collected from cancerous patients and normal volunteers have shown a clear difference in fluorescence intensity
Fluorescence spectroscopy has the potential to identify discriminatory signatures, crucial for ea... more Fluorescence spectroscopy has the potential to identify discriminatory signatures, crucial for early diagnosis of cervical cancer. We demonstrate here the design, fabrication and testing of a 3D printed smartphone based spectroscopic device. Polarized fluorescence and elastic scattering spectra are captured through the device using a 405 nm laser and a white LED source respectively. The device has been calibrated by comparison of spectra of standard fluorophores (Flavin adenine dinucleotide, fluorescein, rhodamine, and porphyrin) with the corresponding spectra collected from a commercial spectrometer. A few cervical tissue spectra have also been captured for proof of its applicability as a portable, standalone device for the collection of intrinsic fluorescence spectra from human cervix.
In this study a hand held probe has been automated using a motorized stage and LabVIEW based cont... more In this study a hand held probe has been automated using a motorized stage and LabVIEW based control and acquisition system for in-vitro cervical precancer diagnosis. The stage movement is controlled by two motors for vertical and horizontal movement while a third motor is utilized for changing the polarization state. The data acquisition and storing was thus performed by moving the probe to a specific site, acquiring polarized fluorescence and elastic scattering signals and creating a user friendly graphical user interface(GUI) panel to suit our needs. Another GUI in MATLAB has also been developed for the real time analysis of data captured through the automatic acquisition system. Three windows were created inside the GUI to display calculated intrinsic fluorescence, for statistical analysis and classification. Principal component analysis was applied to extract the features and classification was done by Mahalanobis distance based algorithm. The classification results have been p...
In this work we have developed a novel rGO-MWCNT (reduced graphene oxide-multiwalled carbon nanot... more In this work we have developed a novel rGO-MWCNT (reduced graphene oxide-multiwalled carbon nanotube) nanocomposite material with Poly-L-Lysine functionalization which can be used for detection of biomolecules with enhanced sensitivity. The reduced GO sheets are found to play a major role as a connector and helps in the assembly of bundles of carbon nanotubes (CNTs) which may sometime play a role of upstanding nanostructures. The overall composite structure is further fully functionalized resulting in an overall high density of amino groups that can be used to capture biomolecules. The sensitivity of the as synthesized film is tested by the oxidation of cholesterol through cholesterol oxidase enzyme that is biochemically immobilized over these composite films. The test for the immobilization density of the novel films are carried out by mounting these films on sensitive thin section static micro/nano-cantilever platforms. The platforms have capability to measure cholesterol traces i...
An in-house fabricated portable device has been tested to detect cervical precancer through the i... more An in-house fabricated portable device has been tested to detect cervical precancer through the intrinsic fluorescence from human cervix of the whole uterus in a clinical setting. A previously validated technique based on simultaneously acquired polarized fluorescence and polarized elastic scattering spectra from a turbid medium is used to extract the intrinsic fluorescence. Using a diode laser at 405 nm, intrinsic fluorescence of flavin adenine dinucleotide, which is the dominant fluorophore and other contributing fluorophores in the epithelium of cervical tissue, has been extracted. Different grades of cervical precancer (cervical intraepithelial neoplasia; CIN) have been discriminated using principal component analysis-based Mahalanobis distance and linear discriminant analysis. Normal, CIN I and CIN II samples have been discriminated from one another with high sensitivity and specificity at 95% confidence level. This ex vivo study with cervix of whole uterus samples immediately ...
MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last d... more MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last decade. Presently, the need has come to scale down to nanoscale cantilevers for better and faster sensing. Previously, metallic cantilevers were mostly used for biochemical/analyte detection which is more expensive compared to the polymeric ones. Arrays of sensors can be fabricated easily as SU-8 is highly resistant to chemicals. In addition, SU-8 is also biocompatible, making it the most suitable material for biochemical sensors. Furthermore, due to its low Young’s modulus, high sensitivity can be achieved. Polymeric nanocantilevers have been used in this study for detection of BSA (Bovine Serum Albumin) in a short time and low amount of concentration. Deflection was measured and observed through optical beam deflection technique and optical diffraction-based approach using high-speed camera.
MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last d... more MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last decade. Presently, the need has come to scale down to nanoscale cantilevers for better and faster sensing. Previously, metallic cantilevers were mostly used for biochemical/analyte detection which is more expensive compared to the polymeric ones. Arrays of sensors can be fabricated easily as SU-8 is highly resistant to chemicals. In addition, SU-8 is also biocompatible, making it the most suitable material for biochemical sensors. Furthermore, due to its low Young’s modulus, high sensitivity can be achieved. Polymeric nanocantilevers have been used in this study for detection of BSA (Bovine Serum Albumin) in a short time and low amount of concentration. Deflection was measured and observed through optical beam deflection technique and optical diffraction-based approach using high-speed camera.
An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. ... more An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. Images collected from cancerous patients and normal volunteers have shown a clear difference in fluorescence intensity.
In this study a hand held probe has been automated using a motorized stage and LabVIEW based cont... more In this study a hand held probe has been automated using a motorized stage and LabVIEW based control and acquisition system for in-vitro cervical precancer diagnosis. The stage movement is controlled by two motors for vertical and horizontal movement while a third motor is utilized for changing the polarization state. The data acquisition and storing was thus performed by moving the probe to a specific site, acquiring polarized fluorescence and elastic scattering signals and creating a user friendly graphical user interface(GUI) panel to suit our needs. Another GUI in MATLAB has also been developed for the real time analysis of data captured through the automatic acquisition system. Three windows were created inside the GUI to display calculated intrinsic fluorescence, for statistical analysis and classification. Principal component analysis was applied to extract the features and classification was done by Mahalanobis distance based algorithm. The classification results have been presented of different grades of cervical cancer
Cervical cancer can be treated and cured if diagnosed at an early stage. Optical devices, develop... more Cervical cancer can be treated and cured if diagnosed at an early stage. Optical devices, developed on smartphone-based platforms, are being tested for this purpose as they are cost-effective, robust, and field portable, showing good efficiency compared to the existing commercial devices. This study reports on the applicability of a 3D printed smartphone-based spectroscopic device (3D-SSD) for the early diagnosis of cervical cancer. The proposed device has the ability to evaluate intrinsic fluorescence (IF) from the collected polarized fluorescence (PF) and elastic-scattering (ES) spectra from cervical tissue samples of different grades. IF spectra of 30 cervical tissue samples have been analyzed and classified using a combination of principal component analysis (PCA) and random forest (RF)-based multi-class classification algorithm with an overall accuracy above 90%. The usage of smartphone for image collection, spectral data analysis, and display makes this device a potential cont...
Translational Biophotonics: Diagnostics and Therapeutics
An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. ... more An imaging device based on fluorescence for in vivo detection of oral cancer has been developed. Images collected from cancerous patients and normal volunteers have shown a clear difference in fluorescence intensity
Fluorescence spectroscopy has the potential to identify discriminatory signatures, crucial for ea... more Fluorescence spectroscopy has the potential to identify discriminatory signatures, crucial for early diagnosis of cervical cancer. We demonstrate here the design, fabrication and testing of a 3D printed smartphone based spectroscopic device. Polarized fluorescence and elastic scattering spectra are captured through the device using a 405 nm laser and a white LED source respectively. The device has been calibrated by comparison of spectra of standard fluorophores (Flavin adenine dinucleotide, fluorescein, rhodamine, and porphyrin) with the corresponding spectra collected from a commercial spectrometer. A few cervical tissue spectra have also been captured for proof of its applicability as a portable, standalone device for the collection of intrinsic fluorescence spectra from human cervix.
In this study a hand held probe has been automated using a motorized stage and LabVIEW based cont... more In this study a hand held probe has been automated using a motorized stage and LabVIEW based control and acquisition system for in-vitro cervical precancer diagnosis. The stage movement is controlled by two motors for vertical and horizontal movement while a third motor is utilized for changing the polarization state. The data acquisition and storing was thus performed by moving the probe to a specific site, acquiring polarized fluorescence and elastic scattering signals and creating a user friendly graphical user interface(GUI) panel to suit our needs. Another GUI in MATLAB has also been developed for the real time analysis of data captured through the automatic acquisition system. Three windows were created inside the GUI to display calculated intrinsic fluorescence, for statistical analysis and classification. Principal component analysis was applied to extract the features and classification was done by Mahalanobis distance based algorithm. The classification results have been p...
In this work we have developed a novel rGO-MWCNT (reduced graphene oxide-multiwalled carbon nanot... more In this work we have developed a novel rGO-MWCNT (reduced graphene oxide-multiwalled carbon nanotube) nanocomposite material with Poly-L-Lysine functionalization which can be used for detection of biomolecules with enhanced sensitivity. The reduced GO sheets are found to play a major role as a connector and helps in the assembly of bundles of carbon nanotubes (CNTs) which may sometime play a role of upstanding nanostructures. The overall composite structure is further fully functionalized resulting in an overall high density of amino groups that can be used to capture biomolecules. The sensitivity of the as synthesized film is tested by the oxidation of cholesterol through cholesterol oxidase enzyme that is biochemically immobilized over these composite films. The test for the immobilization density of the novel films are carried out by mounting these films on sensitive thin section static micro/nano-cantilever platforms. The platforms have capability to measure cholesterol traces i...
An in-house fabricated portable device has been tested to detect cervical precancer through the i... more An in-house fabricated portable device has been tested to detect cervical precancer through the intrinsic fluorescence from human cervix of the whole uterus in a clinical setting. A previously validated technique based on simultaneously acquired polarized fluorescence and polarized elastic scattering spectra from a turbid medium is used to extract the intrinsic fluorescence. Using a diode laser at 405 nm, intrinsic fluorescence of flavin adenine dinucleotide, which is the dominant fluorophore and other contributing fluorophores in the epithelium of cervical tissue, has been extracted. Different grades of cervical precancer (cervical intraepithelial neoplasia; CIN) have been discriminated using principal component analysis-based Mahalanobis distance and linear discriminant analysis. Normal, CIN I and CIN II samples have been discriminated from one another with high sensitivity and specificity at 95% confidence level. This ex vivo study with cervix of whole uterus samples immediately ...
MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last d... more MEMS-based microcantilevers have become an indispensable technique for mass sensing in the last decade. Presently, the need has come to scale down to nanoscale cantilevers for better and faster sensing. Previously, metallic cantilevers were mostly used for biochemical/analyte detection which is more expensive compared to the polymeric ones. Arrays of sensors can be fabricated easily as SU-8 is highly resistant to chemicals. In addition, SU-8 is also biocompatible, making it the most suitable material for biochemical sensors. Furthermore, due to its low Young’s modulus, high sensitivity can be achieved. Polymeric nanocantilevers have been used in this study for detection of BSA (Bovine Serum Albumin) in a short time and low amount of concentration. Deflection was measured and observed through optical beam deflection technique and optical diffraction-based approach using high-speed camera.
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