Trang Mai - Academia.edu (original) (raw)

Papers by Trang Mai

Lecture Notes in Electrical Engineering, 2012

ABSTRACT

Journal of Ambient Intelligence and Humanized Computing, 2012

A recent development of a Semantic Web language is OWL 2, an extension of OWL. So far OWL 2 has b... more A recent development of a Semantic Web language is OWL 2, an extension of OWL. So far OWL 2 has been designed by W3C as the language for representing a web ontology. Earlier we have developed a meta-logical approach for reasoning with Semantic Web ontologies expressed in OWL, with the new extension-OWL 2, in this paper we shall extend our

Policy-driven Dynamic Spectrum Access (DSA) systems are emerging as one of the key technologies t... more Policy-driven Dynamic Spectrum Access (DSA) systems are emerging as one of the key technologies to enable the Department of Defense (DoD) to meet its increasing requirements for access to the electromagnetic spectrum. A key open issue surrounding deployment and continuing development of DSA systems concerns (1) the need to test and evaluate the performance of DSA in avoiding interference to itself and assigned incumbent users and (2) the performance of DSA network in the presence of various types of potential interference. In this paper we describe test framework and concepts to characterize performance of DSA-enabled policy-based radios. Our test framework includes tests to characterize the inherent interference-avoidance characteristics of DSA, such as the time to abandon a channel, as well as tests that address performance implications of a particular DSA policy. The test framework also provides for the ability to inject a relevant electromagnetic environment (EME). The proposed framework is flexible allowing for customization of the relevant test conditions, such as the EME, and facilitates simulation of typical communications events such as network formation and fragmentation.

IEEE Instrumentation and Measurement Technology Conference, 1993

A measurement system was developed to provide integrated signal generation and noise measurement ... more A measurement system was developed to provide integrated signal generation and noise measurement capability for the W-band frequency range, 75-110 GHz. An architecture conforming to established VXI technology was chosen for the implementation. The implementation consisted of integrating commercially available message-based VXI instruments, developing a unique module to provide W-band signal generation and downconversion capability that conformed to VXI specification, and creating software to access the system functionality and control instrument interactions. The authors address all three aspects of the development, but the central focus is on the unique W -band module. Extensions and benefits of the chosen approach are also discussed

2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), 2014

2014 IEEE Military Communications Conference, 2014

2008 IEEE AUTOTESTCON, 2008

Abstract In order to maintain the integrity and safe operation of a power system, a state-of-the-... more Abstract In order to maintain the integrity and safe operation of a power system, a state-of-the-art wiring diagnostic technique is imperative. Joint time-frequency domain reflectometry (JTFDR) is proposed as an ideal solution due to its customizable reference signal and ...

Proceedings AUTOTESTCON 2004., 2004

Page 1. 2004 IEEE AUTOTESTCON FIBER OPTIC TEST EQUIPMENT - EVALUATION OF OTDR DEAD ZONES AND ORLM... more Page 1. 2004 IEEE AUTOTESTCON FIBER OPTIC TEST EQUIPMENT - EVALUATION OF OTDR DEAD ZONES AND ORLM RETURN LOSS Trang V. Mai Joseph A. Molnar Lan H. Tran Naval Research Lab Naval Research Lab Naval Research Lab ...

IEEE Instrumentation and Measurement Technology Conference, 2005

Commercial off the shell (COTS) software/hardware and standalone instruments were used to study t... more Commercial off the shell (COTS) software/hardware and standalone instruments were used to study the feasibility of the development of a QAM evaluation system to support developments of components/sub-systems for high data rate digital communication. Once the concept was proven it was transferred from a rack-and-stack configuration to a standalone test system including its own circuitry and embedded controller. The standalone embedded system includes state-of-the-art A/D, D/A, DSP, FPGA, and development software

IEEE Instrumentation and Measurement Technology Conference, 2004

A major concern relating to the transmission of satellite has been the linearity of available hig... more A major concern relating to the transmission of satellite has been the linearity of available high power amplifier (HPA). Travelling wave tube amplifier (TWTA) offer the greatest efficient and power capacity, but are some limited in linearity. The paper discuss the development a synthetic instrument with most advance DSP, FPGA and very fast DAC - A/D to generate, capture and calculation for BER, EVM as stated in L.H. Tran et al. (2003).The system can configurable to calculate nonlinear pre-distortion neural network's weights for RF power amplifier.

AUTOTESTCON, International Automatic Testing Conference, 2004

This paper discusses methods to evaluate optical time domain reflectormeter (OTDR) and optical re... more This paper discusses methods to evaluate optical time domain reflectormeter (OTDR) and optical return loss meter (ORLM) for field applications. Variable reflectance references for multimode and single mode fibers were built to evaluate the attenuation dead zones of OTDRs. Evaluation of the OTDR attenuation dead zone against a reflectance event of -40 dB with recovery to within 0.5 dB of backscatter reflection is discussed. Methods of measurement related to the IEC 61746 standard are discussed. Optical return loss is another important parameter to determine the quality of a single mode fiber network. A variable reflection standard was built to evaluate ORLM models from three different manufacturers in the range of [10 dB to 45 dB] of return loss with an accuracy of +/-0.5 dB. The standard was verified down to -45 dB return loss within +/-0.5 dB. Testing showed that equipment adapter and fiber connector geometries, fiber contact cleanliness, and skill are also critical to the evaluation. Schematics depict setups are presented. Data collection, data analysis, skills, and difficulties in evaluation process are discussed.

AUTOTESTCON, International Automatic Testing Conference, 2003

In this paper, we discuss how Matlab and standalone COTS instruments can be used to cut down the ... more In this paper, we discuss how Matlab and standalone COTS instruments can be used to cut down the time to study the feasibility of a high speed digital communication test system. The result is a rack-and-stack QAM transceiver with the capability to characterize a device under test (DUT) in terms of bit error rate (BER) and error vector magnitude (EVM). Other characteristics of the DUT are also evaluated. The advantages of COTS rack-and-stack system are time reduction in development and return of capital investment, however, COTS stack-and-rack systems cannot cope with all aspects of high speed modern digital communications. Once the concept is proven, it will be transferred from rack-and-stack to a standalone test system which includes its own circuitry and embedded controller. The standalone digital communications test system is the ultimate goal of this study, since it provides the portability and speed required to support high speed modern digital communications. Advantages and disadvantage of stack-and-rack and standalone QAM test systems are presented.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2015

ABSTRACT Doxorubicin (DOX) is one of the most effective anticancer drugs for treating many types ... more ABSTRACT Doxorubicin (DOX) is one of the most effective anticancer drugs for treating many types of cancer. However, the clinical applications of DOX were hindered because of serious side-effects resulting from the unselective delivery to cancer cell including congestive heart failure, chronic cardiomyopathy and drug resistance. Recently, it has been demonstrated that loading anti-cancer drugs onto drug delivery nanosystems helps to maximize therapeutic efficiency and minimize unwanted side-effects via passive and active targeting mechanisms. In this study we prepared folate decorated DOX loaded PLA-TPGS nanoparticles with the aim of improving the potential as well as reducing the side-effects of DOX. Characteristics of nanoparticles were investigated by field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS) method and Fourier transform infrared spectroscopy (FTIR). Anticancer activity of the nanoparticles was evaluated through cytotoxicity and cellular uptake assays on HeLa and HT29 cancer cell lines. The results showed that prepared drug delivery system had size around 100 nm and exhibited higher cytotoxicity and cellular uptake on both tested HeLa and HT29 cells.

Biomedical Research and Therapy, 2014

The ability of dendritic cells to efficiently present tumor-derived antigens when primed with tum... more The ability of dendritic cells to efficiently present tumor-derived antigens when primed with tumor cell lysates makes them attractive as an approach for cancer treatment. This study aimed to evaluate the effects of dendritic cell transfusion dose on breast cancer tumor growth in a murine model. Dendritic cells were produced from allogeneic bone marrow-derived mononuclear cells that were cultured in RPMI 1640 medium supplemented with 20 ng/mL GM-CSF and 20 ng/mL IL-4 for 7 days. These cells were checked for maturation before being primed with a cancer cell-derived antigen. Cancer cell antigens were produced by a rapid freeze-thaw procedure using a 4T1 cell line. Immature dendritic cells were loaded with 4T1 cellderived antigens. Dendritic cells were transfused into mice bearing tumors at three different doses, included 5.10 4 , 10 5 , and 10 6 cells/mouse with a control consisting of RPMI 1640 media alone. The results showed that dendritic cell therapy inhibited breast cancer tumors in a murine model; however, this effect depended on dendritic cell dose. After 17 days, in the treated groups, tumor size decreased by 43%, 50%, and 87.5% for the doses of 5 × 10 4 , 10 5 , and 10 6 dendritic cells, respectively, while tumor size in the control group decreased by 44%. This result demonstrated that dendritic cell therapy is a promising therapy for breast cancer treatment.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

Curcumin (Cur), extracted from the Curcuma longa L. plant, is well known for its anti-tumor, anti... more Curcumin (Cur), extracted from the Curcuma longa L. plant, is well known for its anti-tumor, anti-oxidant, anti-inflammatory and anti-bacterial properties. Nanofiber mats of polylactic acid (PLA) loading Cur (5 wt%) were fabricated by electrospinning (e-spinning). Morphology and structure of the fibers were characterized by field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The diameters of the obtained fibers varied from 200 to 300 nm. The release capacity of curcumin from curcumin-loaded PLA fibers was investigated in phosphate buffer saline (PBS) containing ethanol. After 24 h, 50% of the curcumin was released from curcumin-loaded PLA fibers. These results of electrospun (e-spun) fibers exhibit the potential for biomedical application.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2011

Being naturally abundant resources and having many interesting physicochemical and biological pro... more Being naturally abundant resources and having many interesting physicochemical and biological properties, chitin/chitosan have been found to be useful in many fields, especially biomedical ones. This paper describes the strategy to design multifunctional, hybrid chitosan-based nanomaterials and test them in some typical biomedical applications.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxym... more In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxymethyl chitosan (OCMCS) on Fe 3 O 4 nanoparticles to be used as hyperthermic thermoseeds. Fe 3 O 4 particles were characterized by physico-chemical methods such as: thermogravimetry analysis (TGA), x-ray diffraction (XRD), Raman spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). The SEM images and XRD patterns showed that the synthesized Fe 3 O 4 nanoparticles were of single phase and spherical shape with 10-15 nm in diameter. The VSM measurements showed that Fe 3 O 4 particles were superparamagnetic with saturation magnetization of 70 emu g −1 . The adsorbed layers of CS and OCMCS on the magnetite surface (Fe 3 O 4 /CS) and (Fe 3 O 4 /OCMCS) were confirmed by FTIR, Raman spectra and SEM. In the ac magnetic field of 80 Oe and 236 kHz, the saturation heating temperatures of the sample Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS were 100 and 98 • C, respectively. At the same concentration of Fe 3 O 4 nanoparticles in suspension, the two magnetic fluids exhibited quite high heating capacity, with different behaviors of concentration dependence. The Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS nanoparticles would serve as good thermoseeds for localized hyperthermia treatment of cancers.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2014

ABSTRACT In this work the synthesis of thermo-sensitive polymer coated magnetic nanoparticles and... more ABSTRACT In this work the synthesis of thermo-sensitive polymer coated magnetic nanoparticles and their inductive heating have been studied. Poly (N-isopropylacrylamide-co-acrylic acid) (NA) polymers were first synthesized by emulsion polymerization of poly(N-isopropylacrylamide) (NIP) in water and followed by encapsulating magnetic nanoparticles (MNPs). As increasing the concentration of acrylic acid (AA), the lower critical solution temperature (LCST) increased, so that with 150% of AA (molar ratio) the LCST reached 42 °C, which is close to the temperature of hyperthermia treatment. Magnetization and ac susceptibility measurements were conducted to depict some characteristics of the NIP-MNPs and NA-MNPs that are related with the loss power. Attempts to analyze the rate of magnetic inductive heating were performed to show the Brownian relaxation origin of additional heat source created by the magnetite nanoparticles capped with thermosensitive polymers. Our results suggest that these thermo-sensitive polymer-coated magnetic nanoparticles show a potential for hyperthermia and drug delivery application.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxym... more In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxymethyl chitosan (OCMCS) on Fe 3 O 4 nanoparticles to be used as hyperthermic thermoseeds. Fe 3 O 4 particles were characterized by physico-chemical methods such as: thermogravimetry analysis (TGA), x-ray diffraction (XRD), Raman spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). The SEM images and XRD patterns showed that the synthesized Fe 3 O 4 nanoparticles were of single phase and spherical shape with 10-15 nm in diameter. The VSM measurements showed that Fe 3 O 4 particles were superparamagnetic with saturation magnetization of 70 emu g −1 . The adsorbed layers of CS and OCMCS on the magnetite surface (Fe 3 O 4 /CS) and (Fe 3 O 4 /OCMCS) were confirmed by FTIR, Raman spectra and SEM. In the ac magnetic field of 80 Oe and 236 kHz, the saturation heating temperatures of the sample Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS were 100 and 98 • C, respectively. At the same concentration of Fe 3 O 4 nanoparticles in suspension, the two magnetic fluids exhibited quite high heating capacity, with different behaviors of concentration dependence. The Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS nanoparticles would serve as good thermoseeds for localized hyperthermia treatment of cancers.

International Journal of Infectious Diseases, 2012

Lecture Notes in Electrical Engineering, 2012

ABSTRACT

Journal of Ambient Intelligence and Humanized Computing, 2012

A recent development of a Semantic Web language is OWL 2, an extension of OWL. So far OWL 2 has b... more A recent development of a Semantic Web language is OWL 2, an extension of OWL. So far OWL 2 has been designed by W3C as the language for representing a web ontology. Earlier we have developed a meta-logical approach for reasoning with Semantic Web ontologies expressed in OWL, with the new extension-OWL 2, in this paper we shall extend our

Policy-driven Dynamic Spectrum Access (DSA) systems are emerging as one of the key technologies t... more Policy-driven Dynamic Spectrum Access (DSA) systems are emerging as one of the key technologies to enable the Department of Defense (DoD) to meet its increasing requirements for access to the electromagnetic spectrum. A key open issue surrounding deployment and continuing development of DSA systems concerns (1) the need to test and evaluate the performance of DSA in avoiding interference to itself and assigned incumbent users and (2) the performance of DSA network in the presence of various types of potential interference. In this paper we describe test framework and concepts to characterize performance of DSA-enabled policy-based radios. Our test framework includes tests to characterize the inherent interference-avoidance characteristics of DSA, such as the time to abandon a channel, as well as tests that address performance implications of a particular DSA policy. The test framework also provides for the ability to inject a relevant electromagnetic environment (EME). The proposed framework is flexible allowing for customization of the relevant test conditions, such as the EME, and facilitates simulation of typical communications events such as network formation and fragmentation.

IEEE Instrumentation and Measurement Technology Conference, 1993

A measurement system was developed to provide integrated signal generation and noise measurement ... more A measurement system was developed to provide integrated signal generation and noise measurement capability for the W-band frequency range, 75-110 GHz. An architecture conforming to established VXI technology was chosen for the implementation. The implementation consisted of integrating commercially available message-based VXI instruments, developing a unique module to provide W-band signal generation and downconversion capability that conformed to VXI specification, and creating software to access the system functionality and control instrument interactions. The authors address all three aspects of the development, but the central focus is on the unique W -band module. Extensions and benefits of the chosen approach are also discussed

2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), 2014

2014 IEEE Military Communications Conference, 2014

2008 IEEE AUTOTESTCON, 2008

Abstract In order to maintain the integrity and safe operation of a power system, a state-of-the-... more Abstract In order to maintain the integrity and safe operation of a power system, a state-of-the-art wiring diagnostic technique is imperative. Joint time-frequency domain reflectometry (JTFDR) is proposed as an ideal solution due to its customizable reference signal and ...

Proceedings AUTOTESTCON 2004., 2004

Page 1. 2004 IEEE AUTOTESTCON FIBER OPTIC TEST EQUIPMENT - EVALUATION OF OTDR DEAD ZONES AND ORLM... more Page 1. 2004 IEEE AUTOTESTCON FIBER OPTIC TEST EQUIPMENT - EVALUATION OF OTDR DEAD ZONES AND ORLM RETURN LOSS Trang V. Mai Joseph A. Molnar Lan H. Tran Naval Research Lab Naval Research Lab Naval Research Lab ...

IEEE Instrumentation and Measurement Technology Conference, 2005

Commercial off the shell (COTS) software/hardware and standalone instruments were used to study t... more Commercial off the shell (COTS) software/hardware and standalone instruments were used to study the feasibility of the development of a QAM evaluation system to support developments of components/sub-systems for high data rate digital communication. Once the concept was proven it was transferred from a rack-and-stack configuration to a standalone test system including its own circuitry and embedded controller. The standalone embedded system includes state-of-the-art A/D, D/A, DSP, FPGA, and development software

IEEE Instrumentation and Measurement Technology Conference, 2004

A major concern relating to the transmission of satellite has been the linearity of available hig... more A major concern relating to the transmission of satellite has been the linearity of available high power amplifier (HPA). Travelling wave tube amplifier (TWTA) offer the greatest efficient and power capacity, but are some limited in linearity. The paper discuss the development a synthetic instrument with most advance DSP, FPGA and very fast DAC - A/D to generate, capture and calculation for BER, EVM as stated in L.H. Tran et al. (2003).The system can configurable to calculate nonlinear pre-distortion neural network's weights for RF power amplifier.

AUTOTESTCON, International Automatic Testing Conference, 2004

This paper discusses methods to evaluate optical time domain reflectormeter (OTDR) and optical re... more This paper discusses methods to evaluate optical time domain reflectormeter (OTDR) and optical return loss meter (ORLM) for field applications. Variable reflectance references for multimode and single mode fibers were built to evaluate the attenuation dead zones of OTDRs. Evaluation of the OTDR attenuation dead zone against a reflectance event of -40 dB with recovery to within 0.5 dB of backscatter reflection is discussed. Methods of measurement related to the IEC 61746 standard are discussed. Optical return loss is another important parameter to determine the quality of a single mode fiber network. A variable reflection standard was built to evaluate ORLM models from three different manufacturers in the range of [10 dB to 45 dB] of return loss with an accuracy of +/-0.5 dB. The standard was verified down to -45 dB return loss within +/-0.5 dB. Testing showed that equipment adapter and fiber connector geometries, fiber contact cleanliness, and skill are also critical to the evaluation. Schematics depict setups are presented. Data collection, data analysis, skills, and difficulties in evaluation process are discussed.

AUTOTESTCON, International Automatic Testing Conference, 2003

In this paper, we discuss how Matlab and standalone COTS instruments can be used to cut down the ... more In this paper, we discuss how Matlab and standalone COTS instruments can be used to cut down the time to study the feasibility of a high speed digital communication test system. The result is a rack-and-stack QAM transceiver with the capability to characterize a device under test (DUT) in terms of bit error rate (BER) and error vector magnitude (EVM). Other characteristics of the DUT are also evaluated. The advantages of COTS rack-and-stack system are time reduction in development and return of capital investment, however, COTS stack-and-rack systems cannot cope with all aspects of high speed modern digital communications. Once the concept is proven, it will be transferred from rack-and-stack to a standalone test system which includes its own circuitry and embedded controller. The standalone digital communications test system is the ultimate goal of this study, since it provides the portability and speed required to support high speed modern digital communications. Advantages and disadvantage of stack-and-rack and standalone QAM test systems are presented.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2015

ABSTRACT Doxorubicin (DOX) is one of the most effective anticancer drugs for treating many types ... more ABSTRACT Doxorubicin (DOX) is one of the most effective anticancer drugs for treating many types of cancer. However, the clinical applications of DOX were hindered because of serious side-effects resulting from the unselective delivery to cancer cell including congestive heart failure, chronic cardiomyopathy and drug resistance. Recently, it has been demonstrated that loading anti-cancer drugs onto drug delivery nanosystems helps to maximize therapeutic efficiency and minimize unwanted side-effects via passive and active targeting mechanisms. In this study we prepared folate decorated DOX loaded PLA-TPGS nanoparticles with the aim of improving the potential as well as reducing the side-effects of DOX. Characteristics of nanoparticles were investigated by field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS) method and Fourier transform infrared spectroscopy (FTIR). Anticancer activity of the nanoparticles was evaluated through cytotoxicity and cellular uptake assays on HeLa and HT29 cancer cell lines. The results showed that prepared drug delivery system had size around 100 nm and exhibited higher cytotoxicity and cellular uptake on both tested HeLa and HT29 cells.

Biomedical Research and Therapy, 2014

The ability of dendritic cells to efficiently present tumor-derived antigens when primed with tum... more The ability of dendritic cells to efficiently present tumor-derived antigens when primed with tumor cell lysates makes them attractive as an approach for cancer treatment. This study aimed to evaluate the effects of dendritic cell transfusion dose on breast cancer tumor growth in a murine model. Dendritic cells were produced from allogeneic bone marrow-derived mononuclear cells that were cultured in RPMI 1640 medium supplemented with 20 ng/mL GM-CSF and 20 ng/mL IL-4 for 7 days. These cells were checked for maturation before being primed with a cancer cell-derived antigen. Cancer cell antigens were produced by a rapid freeze-thaw procedure using a 4T1 cell line. Immature dendritic cells were loaded with 4T1 cellderived antigens. Dendritic cells were transfused into mice bearing tumors at three different doses, included 5.10 4 , 10 5 , and 10 6 cells/mouse with a control consisting of RPMI 1640 media alone. The results showed that dendritic cell therapy inhibited breast cancer tumors in a murine model; however, this effect depended on dendritic cell dose. After 17 days, in the treated groups, tumor size decreased by 43%, 50%, and 87.5% for the doses of 5 × 10 4 , 10 5 , and 10 6 dendritic cells, respectively, while tumor size in the control group decreased by 44%. This result demonstrated that dendritic cell therapy is a promising therapy for breast cancer treatment.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

Curcumin (Cur), extracted from the Curcuma longa L. plant, is well known for its anti-tumor, anti... more Curcumin (Cur), extracted from the Curcuma longa L. plant, is well known for its anti-tumor, anti-oxidant, anti-inflammatory and anti-bacterial properties. Nanofiber mats of polylactic acid (PLA) loading Cur (5 wt%) were fabricated by electrospinning (e-spinning). Morphology and structure of the fibers were characterized by field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The diameters of the obtained fibers varied from 200 to 300 nm. The release capacity of curcumin from curcumin-loaded PLA fibers was investigated in phosphate buffer saline (PBS) containing ethanol. After 24 h, 50% of the curcumin was released from curcumin-loaded PLA fibers. These results of electrospun (e-spun) fibers exhibit the potential for biomedical application.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2011

Being naturally abundant resources and having many interesting physicochemical and biological pro... more Being naturally abundant resources and having many interesting physicochemical and biological properties, chitin/chitosan have been found to be useful in many fields, especially biomedical ones. This paper describes the strategy to design multifunctional, hybrid chitosan-based nanomaterials and test them in some typical biomedical applications.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxym... more In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxymethyl chitosan (OCMCS) on Fe 3 O 4 nanoparticles to be used as hyperthermic thermoseeds. Fe 3 O 4 particles were characterized by physico-chemical methods such as: thermogravimetry analysis (TGA), x-ray diffraction (XRD), Raman spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). The SEM images and XRD patterns showed that the synthesized Fe 3 O 4 nanoparticles were of single phase and spherical shape with 10-15 nm in diameter. The VSM measurements showed that Fe 3 O 4 particles were superparamagnetic with saturation magnetization of 70 emu g −1 . The adsorbed layers of CS and OCMCS on the magnetite surface (Fe 3 O 4 /CS) and (Fe 3 O 4 /OCMCS) were confirmed by FTIR, Raman spectra and SEM. In the ac magnetic field of 80 Oe and 236 kHz, the saturation heating temperatures of the sample Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS were 100 and 98 • C, respectively. At the same concentration of Fe 3 O 4 nanoparticles in suspension, the two magnetic fluids exhibited quite high heating capacity, with different behaviors of concentration dependence. The Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS nanoparticles would serve as good thermoseeds for localized hyperthermia treatment of cancers.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2014

ABSTRACT In this work the synthesis of thermo-sensitive polymer coated magnetic nanoparticles and... more ABSTRACT In this work the synthesis of thermo-sensitive polymer coated magnetic nanoparticles and their inductive heating have been studied. Poly (N-isopropylacrylamide-co-acrylic acid) (NA) polymers were first synthesized by emulsion polymerization of poly(N-isopropylacrylamide) (NIP) in water and followed by encapsulating magnetic nanoparticles (MNPs). As increasing the concentration of acrylic acid (AA), the lower critical solution temperature (LCST) increased, so that with 150% of AA (molar ratio) the LCST reached 42 °C, which is close to the temperature of hyperthermia treatment. Magnetization and ac susceptibility measurements were conducted to depict some characteristics of the NIP-MNPs and NA-MNPs that are related with the loss power. Attempts to analyze the rate of magnetic inductive heating were performed to show the Brownian relaxation origin of additional heat source created by the magnetite nanoparticles capped with thermosensitive polymers. Our results suggest that these thermo-sensitive polymer-coated magnetic nanoparticles show a potential for hyperthermia and drug delivery application.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxym... more In this study magnetic fluids were manufactured by the adsorption of chitosan (CS) and O-carboxymethyl chitosan (OCMCS) on Fe 3 O 4 nanoparticles to be used as hyperthermic thermoseeds. Fe 3 O 4 particles were characterized by physico-chemical methods such as: thermogravimetry analysis (TGA), x-ray diffraction (XRD), Raman spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). The SEM images and XRD patterns showed that the synthesized Fe 3 O 4 nanoparticles were of single phase and spherical shape with 10-15 nm in diameter. The VSM measurements showed that Fe 3 O 4 particles were superparamagnetic with saturation magnetization of 70 emu g −1 . The adsorbed layers of CS and OCMCS on the magnetite surface (Fe 3 O 4 /CS) and (Fe 3 O 4 /OCMCS) were confirmed by FTIR, Raman spectra and SEM. In the ac magnetic field of 80 Oe and 236 kHz, the saturation heating temperatures of the sample Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS were 100 and 98 • C, respectively. At the same concentration of Fe 3 O 4 nanoparticles in suspension, the two magnetic fluids exhibited quite high heating capacity, with different behaviors of concentration dependence. The Fe 3 O 4 /CS and Fe 3 O 4 /OCMCS nanoparticles would serve as good thermoseeds for localized hyperthermia treatment of cancers.

International Journal of Infectious Diseases, 2012