Sadegh Nourbakhsh - Academia.edu (original) (raw)

Papers by Sadegh Nourbakhsh

International Journal of Biological Macromolecules

Journal of Microencapsulation

AIM In this study chitosan-coated niosome (ChN) was utilized for bioavailability enhancement of c... more AIM In this study chitosan-coated niosome (ChN) was utilized for bioavailability enhancement of curcumin (Cn) and boswellic acids (BAs). METHODS The bare niosome (BN) was prepared by the heating method and optimized by using the mixture design procedure. Physicochemical stability, as well as the in vitro release, and bioavailability of Cn and BAs in BN and ChN were studied. RESULTS The optimized BN had a mean diameter of 70.00 ± 0.21 nm and surface charge of -31.00 ± 0.25 mv, which changed to 60.01 ± 0.20 nm and +40.00 ± 0, respectively, in ChN. In-vitro digestion study revealed chitosan layer augmented the bioavailability of Cn and BAs to 79.02 ± 0.13 and 81 ± 0.10, respectively. The chitosan layer obviously improved the physical stability of Cn and BA in the niosome vehicle, by means of vesicle size, zeta potential, and encapsulation efficiency. CONCLUSION The Chitosan-coated niosome was considered to be promising delivery system for increasing the bioavailability of Cn and BAs.

Laser soldering is based on applying some soldering material (albumin) onto the approximated edge... more Laser soldering is based on applying some soldering material (albumin) onto the approximated edges of the cut and heating the solder (and the underlying tissues) by a laser beam. Endogenous and exogenous materials such as indocyanine green (ICG) are often added to solders to enhance light absorption. Gold nanoshells are new materials which have an optical response dictated by the plasmon resonance. The wavelength at which the resonance occurs depends on the core and shell sizes, allowing nanoshells to be tailored for particular applications. The purposes of this study was use combination of ICG and different concentration of gold nanoshells for skin tissue soldering and also to examine the effect of laser soldering parameters on the properties of repaired skin. Two mixtures of albumin solder and different combinations of ICG and gold nanoshells were prepared. A full thickness incision of 2×20 mm2 was made on the surface and after addition of mixtures it was irradiated by an 810nm di...

Iranian Journal of Medical Physics, 2009

Introduction: Laser tissue soldering using albumin and indocyanine green dye (ICG) is an effectiv... more Introduction: Laser tissue soldering using albumin and indocyanine green dye (ICG) is an effective technique utilized in various surgical procedures. The purpose of this study was to perform laser soldering of rat skin under a feedback control system and compare the results with those obtained using standard sutures. Material and Methods: Skin incisions were made over eight rats’ dorsa, which were subsequently closed using different wound closure interventions in two groups: (a) using a temperature controlled infrared detector or (b) by suture. Tensile strengths were measured at 2, 5, 7 and 10 days post-incision. Histological examination was performed at the time of sacrifice. Results: Tensile strength results showed that during the initial days following the incisions, the tensile strengths of the sutured samples were greater than the laser samples. However, 10 days after the incisions, the tensile strengths of the laser soldered incisions were higher than the sutured cuts. Histopa...

Gold nanoshells are a new type of nanoparticles including dielectric cores with a continuous thin... more Gold nanoshells are a new type of nanoparticles including dielectric cores with a continuous thin layer of gold. By varying the core diameter, shell thickness, and the ratio of these parameters, the optical properties of gold nanoshells can be tuned to have maximum absorption in the visible and near infrared spectrum range. The purpose of this research was to synthesize gold coated SiO2 nanoshells for biomedical applications particularly laser tissue soldering. Nanoshells were * رايداتسا ** داتسا D ow nl oa de d fr om ja m e. iu t.a c. ir at 8 :2 6 IR S T o n T ue sd ay J an ua ry 2 1s t 2 02 0

International Journal of Polymeric Materials and Polymeric Biomaterials, 2018

Polycaprolactone is a biodegradable and biocompatible polyester which has a wide range of applica... more Polycaprolactone is a biodegradable and biocompatible polyester which has a wide range of applications in tissue engineering. Electrospinning, the versatile technique, used for the fabrication of fibrous scaffolds, which is widely used in tissue engineering, due to the ability of fabrication of nano/micro-scale fiber scaffolds. Polycaprolactone nanofiber scaffolds are widely used in tissue engineering and drug delivery. Polycaprolactone can be used in a wide variety of scaffolds construction. In this review, we will discuss the recent advances in the electrospinning of polycaprolactone nanofiber scaffolds in bone, cardiovascular, nerve, and skin tissue engineering.

Journal of Sol-Gel Science and Technology, 2018

Recently, cobalt ferrite nanoparticles have attracted much attention due to their physical, chemi... more Recently, cobalt ferrite nanoparticles have attracted much attention due to their physical, chemical and magnetic properties. Numerous studies have focused on facile production of these nanoparticles. In this study, CoFe 2 O 4 , Zn 0.4 Co 0.6 Fe 2 O 4 , Cd 0.4 Co 0.6 Fe 2 O 4 , and Cd 0.2 Zn 0.2 Co 0.6 Fe 2 O 4 were successfully synthesized by using economical and simple microwavemodified Pechini sol-gel method, calcined by microwave radiation. The nanoparticles were characterized by some techniques such as X-ray diffraction, energy dispersive spectroscopy, field emission scanning electron microscopy, Fourier transform infrared, and vibrating sample magnetometer analyses. The X-ray diffraction, energy dispersive spectroscopy and Fourier transform infrared results confirmed the formation of CoFe 2 O 4 nanoparticles. Fourier transform infrared indicated two fundamental absorption bands of spinel structure. The diameters of the spherical and rod form structures of nanoparticles ranged from 18 to 39 nm. The results indicated that the substitution of Co with Zn and Cd in cobalt ferrite influenced the physical properties, magnetic properties and cytotoxicity of these nanoparticles as medical devices. Zn doping had the significant effect on decreasing the size of cobalt ferrite nanoparticles and improving the magnetic properties. Zn-doped nanoparticles exhibited super paramagnetic behavior (coercivity was nearly 0oe and saturation magnetization was 52.78 emu/g). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (in vitro cytotoxicity MTT assay) assay confirmed that all samples were non-toxic and potentially can be used in biomedical application.

IFMBE Proceedings, 2008

Laser tissue soldering based on protein as biological glues and other compounds can provide great... more Laser tissue soldering based on protein as biological glues and other compounds can provide greater bond strength and less collateral damage. Endogenous and exogenous materials such as indocyanine green (ICG) are often added to solders to enhance light absorption. The purpose of this study was to examine the impact of static and dynamic modes of laser soldering on the thermo-physical properties of the sheep skin. A mixture of albumin solder and ICG was prepared with the ratio of 1000:1 and then the coated samples were irradiated by a diode laser (≈ 800nm) at different conditions. Temperature rise, number of scan (Ns), and scan velocity (Vs) were investigated in dynamic mode. The results showed that at each laser power density (I) the tissue tensile strength (σt) of cuts repaired in dynamic mode is higher than static mode. However, in practice to have an optimal condition for skin closure the above parameters must be carefully studied. In our case, the results showed that the σt increases by increasing both Ns and I. But, also it has been equally shown that at lower Vs, hence higher temperature, a higher value of σt is achieved. It is therefore imperative to consider the trade off between the scan and the surface temperature for achieving the optimum operating condition. Finally, it is tentatively concluded that the skin temperature should not exceed 90°C at any time of work, then the acceptable conditions in our experiment correspond to I= 47 Wcm−2, σt =300gr, Ns=8, Vs=0.3mms−1.

IFMBE Proceedings, 2008

Tissue laser soldering is a method of closure of incisions that in principle may have advantages ... more Tissue laser soldering is a method of closure of incisions that in principle may have advantages over conventional closure methods. It is a non-contact technique, continuous and watertight and the procedure is faster and requires less skill to master. However, in practice there have been difficulties in obtaining strong and reliable welding. The quality of the weld depends on the ability to monitor and control the surface temperature of soldering zone during the procedure. Our goal was to use laser soldering to seal cuts in rat skin under temperature feed-back control and compare the results with standard sutures. Full-thickness incision created on the dorsum of rats and albumin solder with Indocyanine- Green (ICG) dye was added between the incision edges and photothermally coagulated with diode laser. We have developed an automated soldering system based on diode laser, IR detector, photodiode, digital thermocouple and camera. The true temperature of the heated tissue was determined by using and improved calibration soft ware method. Laser soldering was carried out spot by spot until it reached a preset value of 70–75°C at each point. The tensile strength of laser soldered cuts was measured after 2–10 days postoperatively and was found comparable to that of sutured cuts. Histopathological studies showed better healing and less inflammatory reactions than that caused by standard sutures after 7th day.

Medical Laser Application, 2011

Background and objective: Gold-coated silica core nanoparticles have an optical response dictated... more Background and objective: Gold-coated silica core nanoparticles have an optical response dictated by plasmon resonance. The wavelength at which the resonance occurs depends on the core and shell sizes, allowing nanoshells to be tailored to particular applications. The purpose of this in vitro study was to synthesize and use different concentrations of gold nanoshells as exogenous material for skin tissue soldering and to examine the effect of laser soldering parameters (irradiance, number of scans and scan velocity) on the properties of repaired skin. Materials and methods: Two protein solder solutions mixed with albumin solder and two different gold nanoshell concentrations (1 and 2 ml) were prepared. A 2-mm-thick, 20-mm-long incision was made on the surface of depilated sheep skin strips using a surgical blade, and after the addition of the solder solution, it was irradiated with a diode laser (810 nm), varying the irradiance I (24-83 W/cm 2), the number of laser scans N s (2-10 scans), and the scan velocity v s (0.2-0.42 mm/s). The temperature T was monitored using a digital K-type thermometer (CHY502A1, CHY Firemate Co., Taiwan) that was positioned under the skin with a probe diameter of 0.5 mm and a response time of 0.1 s. Approximately 30 min after the completion of the soldering process, the tensile strength σ was evaluated in a tensile test. Results: The results show that the tensile strength of the repaired skin increased with increasing laser irradiance for both gold nanoshell concentrations. At a constant irradiance, the tensile strength of the repaired incisions increased with increasing N s and decreasing v s. A higher irradiance resulted in a larger tissue temperature rise. Conclusion: It was demonstrated that gold nanoshells can be used for laser tissue soldering, provided that the operating conditions are carefully optimized. In our case the optimal parameters were: σ = 0.16 N/mm 2 at I ∼ 60 W/cm 2 , T ∼ 65 • C, N s = 10 and v s = 0.2 mm/s.

Journal of Modern Physics, 2011

We described the synthesis of Au coated SiO 2 nanoshells linked with NH 2 biomolecular ligands us... more We described the synthesis of Au coated SiO 2 nanoshells linked with NH 2 biomolecular ligands using a simple wet chemical method with a particular application for laser tissue soldering. Tunable nanoshells were prepared by using different gold colloidal concentrations. The nanoshells are characterized by UV-vis spectroscopy, FTIR, XRD and AFM. The FTIR results confirmed the functionalized surfaces of silica nanoparticles with NH 2 terminal groups. A broad absorption was observed between 470-600 nm with a maximum range between 530-560 nm. Based on the XRD results three main peaks of Au (111), (200) and (220) were identified. In addition, AFM results showed that the diameter of silica core was between 90-110 nm with gold shell thickness between 10-30 nm. A possible tissue soldering using gold nanoshells and laser-induced thermal effect based on surface plasmon resonance is demonstrated. In our case this corresponds to 90˚C (i.e. below vaporization) using the higher gold concentration (2 ml) at 60 W•cm-2 .

2007 Conference on Lasers and Electro-Optics (CLEO), 2007

The optical and thermal parameters are optimized for an invitro skin closure using a 10 W diode l... more The optical and thermal parameters are optimized for an invitro skin closure using a 10 W diode laser at 800 nm. The major results showed the effects of static and dynamic modes of treatments on tissue tensile strength.

Journal of Sol-Gel Science and Technology, 2015

In this study, the surface of the hydrothermally synthesized SBA-16 was modified with 3-aminoprop... more In this study, the surface of the hydrothermally synthesized SBA-16 was modified with 3-aminopropyltriethoxysilane (APTES) as a controlled drug delivery system. In this case, ibuprofen was chosen as a drug. Furthermore, it was loaded into the SBA-16 base and functionalized SBA-16. Then, the adsorption and release properties of mention samples were studied. In addition, mesoporous materials were characterized using X-ray diffraction, fourier-transform infra-red spectroscopy, N 2 adsorption/desorption analysis and ultraviolet spectroscopy. The results showed that adsorption and release behavior of ibuprofen were extremely depended on various surface properties of SBA-16 particles. Furthermore, it was observed that the sample with a higher percent loaded of ibuprofen exhibited a higher percent of the ibuprofen released molecules in a phosphate buffer solution.

Lasers in Medical Science, 2007

The effect of the 488-nm wavelength of argon laser at different power densities and irradiation t... more The effect of the 488-nm wavelength of argon laser at different power densities and irradiation times on the degree of conversion (DC), temperature rise, water sorption, solubility, flexural strength, flexural modulus, and microhardness of bisphenole A glycol dimethacrylate and triethylen glycol dimethacrylate with a mass ratio of 75:25 was studied. Camphorquinone and N,N′-dimethyl aminoethyl methacrylate were added to the monomer as a photo initiator system. The DC% of the resin was measured using Fourier transform infrared spectroscopy. The maximum DC% (50%), which was reached in 20 s, and temperature rise because of the reaction (13.5°C) were both higher at 1075 than 700 mW/cm2. Water sorption and solubility were measured according to ISO4049, which in our case were 23.7 and 2.20 μg/mm3 at 1075 mW/cm2, respectively. A flexural modulus of 1.1 GPa and microhardness of 19.6 kg/mm2 were achieved above the power density. No significant difference was observed (i.e., p > 0.05) for water sorption and flexural strength at 700 and 1075 mW/cm2.

Lasers in Medical Science, 2010

Lasers in Medical Science, 2009

Laser tissue soldering based on protein as biological glues and other compounds can provide great... more Laser tissue soldering based on protein as biological glues and other compounds can provide greater bond strength and less collateral damage. Endogenous and exogenous materials such as indocyanine green (ICG) are often added to solders to enhance light absorption. The purpose of this in vitro study was to examine the impact of different parameters of laser soldering on the thermo-physical properties of the skin. A mixture of albumin solder and ICG was prepared, and then the coated samples were irradiated by an 810 nm diode laser under different conditions. The temperature rise, number of scans (N(s)), and scan velocity (V(s)) were investigated in this study. The results showed that, at each laser irradiance (I), the tensile strength (sigma) of incisions repaired in static mode was higher than in dynamic mode and that the sigma increased with both increasing N(s) and increasing I. It is therefore important to consider the trade off between scan velocity and surface temperature for achieving an optimum operating condition.

International Journal of Biological Macromolecules

Journal of Microencapsulation

AIM In this study chitosan-coated niosome (ChN) was utilized for bioavailability enhancement of c... more AIM In this study chitosan-coated niosome (ChN) was utilized for bioavailability enhancement of curcumin (Cn) and boswellic acids (BAs). METHODS The bare niosome (BN) was prepared by the heating method and optimized by using the mixture design procedure. Physicochemical stability, as well as the in vitro release, and bioavailability of Cn and BAs in BN and ChN were studied. RESULTS The optimized BN had a mean diameter of 70.00 ± 0.21 nm and surface charge of -31.00 ± 0.25 mv, which changed to 60.01 ± 0.20 nm and +40.00 ± 0, respectively, in ChN. In-vitro digestion study revealed chitosan layer augmented the bioavailability of Cn and BAs to 79.02 ± 0.13 and 81 ± 0.10, respectively. The chitosan layer obviously improved the physical stability of Cn and BA in the niosome vehicle, by means of vesicle size, zeta potential, and encapsulation efficiency. CONCLUSION The Chitosan-coated niosome was considered to be promising delivery system for increasing the bioavailability of Cn and BAs.

Laser soldering is based on applying some soldering material (albumin) onto the approximated edge... more Laser soldering is based on applying some soldering material (albumin) onto the approximated edges of the cut and heating the solder (and the underlying tissues) by a laser beam. Endogenous and exogenous materials such as indocyanine green (ICG) are often added to solders to enhance light absorption. Gold nanoshells are new materials which have an optical response dictated by the plasmon resonance. The wavelength at which the resonance occurs depends on the core and shell sizes, allowing nanoshells to be tailored for particular applications. The purposes of this study was use combination of ICG and different concentration of gold nanoshells for skin tissue soldering and also to examine the effect of laser soldering parameters on the properties of repaired skin. Two mixtures of albumin solder and different combinations of ICG and gold nanoshells were prepared. A full thickness incision of 2×20 mm2 was made on the surface and after addition of mixtures it was irradiated by an 810nm di...

Iranian Journal of Medical Physics, 2009

Introduction: Laser tissue soldering using albumin and indocyanine green dye (ICG) is an effectiv... more Introduction: Laser tissue soldering using albumin and indocyanine green dye (ICG) is an effective technique utilized in various surgical procedures. The purpose of this study was to perform laser soldering of rat skin under a feedback control system and compare the results with those obtained using standard sutures. Material and Methods: Skin incisions were made over eight rats’ dorsa, which were subsequently closed using different wound closure interventions in two groups: (a) using a temperature controlled infrared detector or (b) by suture. Tensile strengths were measured at 2, 5, 7 and 10 days post-incision. Histological examination was performed at the time of sacrifice. Results: Tensile strength results showed that during the initial days following the incisions, the tensile strengths of the sutured samples were greater than the laser samples. However, 10 days after the incisions, the tensile strengths of the laser soldered incisions were higher than the sutured cuts. Histopa...

Gold nanoshells are a new type of nanoparticles including dielectric cores with a continuous thin... more Gold nanoshells are a new type of nanoparticles including dielectric cores with a continuous thin layer of gold. By varying the core diameter, shell thickness, and the ratio of these parameters, the optical properties of gold nanoshells can be tuned to have maximum absorption in the visible and near infrared spectrum range. The purpose of this research was to synthesize gold coated SiO2 nanoshells for biomedical applications particularly laser tissue soldering. Nanoshells were * رايداتسا ** داتسا D ow nl oa de d fr om ja m e. iu t.a c. ir at 8 :2 6 IR S T o n T ue sd ay J an ua ry 2 1s t 2 02 0

International Journal of Polymeric Materials and Polymeric Biomaterials, 2018

Polycaprolactone is a biodegradable and biocompatible polyester which has a wide range of applica... more Polycaprolactone is a biodegradable and biocompatible polyester which has a wide range of applications in tissue engineering. Electrospinning, the versatile technique, used for the fabrication of fibrous scaffolds, which is widely used in tissue engineering, due to the ability of fabrication of nano/micro-scale fiber scaffolds. Polycaprolactone nanofiber scaffolds are widely used in tissue engineering and drug delivery. Polycaprolactone can be used in a wide variety of scaffolds construction. In this review, we will discuss the recent advances in the electrospinning of polycaprolactone nanofiber scaffolds in bone, cardiovascular, nerve, and skin tissue engineering.

Journal of Sol-Gel Science and Technology, 2018

Recently, cobalt ferrite nanoparticles have attracted much attention due to their physical, chemi... more Recently, cobalt ferrite nanoparticles have attracted much attention due to their physical, chemical and magnetic properties. Numerous studies have focused on facile production of these nanoparticles. In this study, CoFe 2 O 4 , Zn 0.4 Co 0.6 Fe 2 O 4 , Cd 0.4 Co 0.6 Fe 2 O 4 , and Cd 0.2 Zn 0.2 Co 0.6 Fe 2 O 4 were successfully synthesized by using economical and simple microwavemodified Pechini sol-gel method, calcined by microwave radiation. The nanoparticles were characterized by some techniques such as X-ray diffraction, energy dispersive spectroscopy, field emission scanning electron microscopy, Fourier transform infrared, and vibrating sample magnetometer analyses. The X-ray diffraction, energy dispersive spectroscopy and Fourier transform infrared results confirmed the formation of CoFe 2 O 4 nanoparticles. Fourier transform infrared indicated two fundamental absorption bands of spinel structure. The diameters of the spherical and rod form structures of nanoparticles ranged from 18 to 39 nm. The results indicated that the substitution of Co with Zn and Cd in cobalt ferrite influenced the physical properties, magnetic properties and cytotoxicity of these nanoparticles as medical devices. Zn doping had the significant effect on decreasing the size of cobalt ferrite nanoparticles and improving the magnetic properties. Zn-doped nanoparticles exhibited super paramagnetic behavior (coercivity was nearly 0oe and saturation magnetization was 52.78 emu/g). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (in vitro cytotoxicity MTT assay) assay confirmed that all samples were non-toxic and potentially can be used in biomedical application.

IFMBE Proceedings, 2008

Laser tissue soldering based on protein as biological glues and other compounds can provide great... more Laser tissue soldering based on protein as biological glues and other compounds can provide greater bond strength and less collateral damage. Endogenous and exogenous materials such as indocyanine green (ICG) are often added to solders to enhance light absorption. The purpose of this study was to examine the impact of static and dynamic modes of laser soldering on the thermo-physical properties of the sheep skin. A mixture of albumin solder and ICG was prepared with the ratio of 1000:1 and then the coated samples were irradiated by a diode laser (≈ 800nm) at different conditions. Temperature rise, number of scan (Ns), and scan velocity (Vs) were investigated in dynamic mode. The results showed that at each laser power density (I) the tissue tensile strength (σt) of cuts repaired in dynamic mode is higher than static mode. However, in practice to have an optimal condition for skin closure the above parameters must be carefully studied. In our case, the results showed that the σt increases by increasing both Ns and I. But, also it has been equally shown that at lower Vs, hence higher temperature, a higher value of σt is achieved. It is therefore imperative to consider the trade off between the scan and the surface temperature for achieving the optimum operating condition. Finally, it is tentatively concluded that the skin temperature should not exceed 90°C at any time of work, then the acceptable conditions in our experiment correspond to I= 47 Wcm−2, σt =300gr, Ns=8, Vs=0.3mms−1.

IFMBE Proceedings, 2008

Tissue laser soldering is a method of closure of incisions that in principle may have advantages ... more Tissue laser soldering is a method of closure of incisions that in principle may have advantages over conventional closure methods. It is a non-contact technique, continuous and watertight and the procedure is faster and requires less skill to master. However, in practice there have been difficulties in obtaining strong and reliable welding. The quality of the weld depends on the ability to monitor and control the surface temperature of soldering zone during the procedure. Our goal was to use laser soldering to seal cuts in rat skin under temperature feed-back control and compare the results with standard sutures. Full-thickness incision created on the dorsum of rats and albumin solder with Indocyanine- Green (ICG) dye was added between the incision edges and photothermally coagulated with diode laser. We have developed an automated soldering system based on diode laser, IR detector, photodiode, digital thermocouple and camera. The true temperature of the heated tissue was determined by using and improved calibration soft ware method. Laser soldering was carried out spot by spot until it reached a preset value of 70–75°C at each point. The tensile strength of laser soldered cuts was measured after 2–10 days postoperatively and was found comparable to that of sutured cuts. Histopathological studies showed better healing and less inflammatory reactions than that caused by standard sutures after 7th day.

Medical Laser Application, 2011

Background and objective: Gold-coated silica core nanoparticles have an optical response dictated... more Background and objective: Gold-coated silica core nanoparticles have an optical response dictated by plasmon resonance. The wavelength at which the resonance occurs depends on the core and shell sizes, allowing nanoshells to be tailored to particular applications. The purpose of this in vitro study was to synthesize and use different concentrations of gold nanoshells as exogenous material for skin tissue soldering and to examine the effect of laser soldering parameters (irradiance, number of scans and scan velocity) on the properties of repaired skin. Materials and methods: Two protein solder solutions mixed with albumin solder and two different gold nanoshell concentrations (1 and 2 ml) were prepared. A 2-mm-thick, 20-mm-long incision was made on the surface of depilated sheep skin strips using a surgical blade, and after the addition of the solder solution, it was irradiated with a diode laser (810 nm), varying the irradiance I (24-83 W/cm 2), the number of laser scans N s (2-10 scans), and the scan velocity v s (0.2-0.42 mm/s). The temperature T was monitored using a digital K-type thermometer (CHY502A1, CHY Firemate Co., Taiwan) that was positioned under the skin with a probe diameter of 0.5 mm and a response time of 0.1 s. Approximately 30 min after the completion of the soldering process, the tensile strength σ was evaluated in a tensile test. Results: The results show that the tensile strength of the repaired skin increased with increasing laser irradiance for both gold nanoshell concentrations. At a constant irradiance, the tensile strength of the repaired incisions increased with increasing N s and decreasing v s. A higher irradiance resulted in a larger tissue temperature rise. Conclusion: It was demonstrated that gold nanoshells can be used for laser tissue soldering, provided that the operating conditions are carefully optimized. In our case the optimal parameters were: σ = 0.16 N/mm 2 at I ∼ 60 W/cm 2 , T ∼ 65 • C, N s = 10 and v s = 0.2 mm/s.

Journal of Modern Physics, 2011

We described the synthesis of Au coated SiO 2 nanoshells linked with NH 2 biomolecular ligands us... more We described the synthesis of Au coated SiO 2 nanoshells linked with NH 2 biomolecular ligands using a simple wet chemical method with a particular application for laser tissue soldering. Tunable nanoshells were prepared by using different gold colloidal concentrations. The nanoshells are characterized by UV-vis spectroscopy, FTIR, XRD and AFM. The FTIR results confirmed the functionalized surfaces of silica nanoparticles with NH 2 terminal groups. A broad absorption was observed between 470-600 nm with a maximum range between 530-560 nm. Based on the XRD results three main peaks of Au (111), (200) and (220) were identified. In addition, AFM results showed that the diameter of silica core was between 90-110 nm with gold shell thickness between 10-30 nm. A possible tissue soldering using gold nanoshells and laser-induced thermal effect based on surface plasmon resonance is demonstrated. In our case this corresponds to 90˚C (i.e. below vaporization) using the higher gold concentration (2 ml) at 60 W•cm-2 .

2007 Conference on Lasers and Electro-Optics (CLEO), 2007

The optical and thermal parameters are optimized for an invitro skin closure using a 10 W diode l... more The optical and thermal parameters are optimized for an invitro skin closure using a 10 W diode laser at 800 nm. The major results showed the effects of static and dynamic modes of treatments on tissue tensile strength.

Journal of Sol-Gel Science and Technology, 2015

In this study, the surface of the hydrothermally synthesized SBA-16 was modified with 3-aminoprop... more In this study, the surface of the hydrothermally synthesized SBA-16 was modified with 3-aminopropyltriethoxysilane (APTES) as a controlled drug delivery system. In this case, ibuprofen was chosen as a drug. Furthermore, it was loaded into the SBA-16 base and functionalized SBA-16. Then, the adsorption and release properties of mention samples were studied. In addition, mesoporous materials were characterized using X-ray diffraction, fourier-transform infra-red spectroscopy, N 2 adsorption/desorption analysis and ultraviolet spectroscopy. The results showed that adsorption and release behavior of ibuprofen were extremely depended on various surface properties of SBA-16 particles. Furthermore, it was observed that the sample with a higher percent loaded of ibuprofen exhibited a higher percent of the ibuprofen released molecules in a phosphate buffer solution.

Lasers in Medical Science, 2007

The effect of the 488-nm wavelength of argon laser at different power densities and irradiation t... more The effect of the 488-nm wavelength of argon laser at different power densities and irradiation times on the degree of conversion (DC), temperature rise, water sorption, solubility, flexural strength, flexural modulus, and microhardness of bisphenole A glycol dimethacrylate and triethylen glycol dimethacrylate with a mass ratio of 75:25 was studied. Camphorquinone and N,N′-dimethyl aminoethyl methacrylate were added to the monomer as a photo initiator system. The DC% of the resin was measured using Fourier transform infrared spectroscopy. The maximum DC% (50%), which was reached in 20 s, and temperature rise because of the reaction (13.5°C) were both higher at 1075 than 700 mW/cm2. Water sorption and solubility were measured according to ISO4049, which in our case were 23.7 and 2.20 μg/mm3 at 1075 mW/cm2, respectively. A flexural modulus of 1.1 GPa and microhardness of 19.6 kg/mm2 were achieved above the power density. No significant difference was observed (i.e., p > 0.05) for water sorption and flexural strength at 700 and 1075 mW/cm2.

Lasers in Medical Science, 2010

Lasers in Medical Science, 2009

Laser tissue soldering based on protein as biological glues and other compounds can provide great... more Laser tissue soldering based on protein as biological glues and other compounds can provide greater bond strength and less collateral damage. Endogenous and exogenous materials such as indocyanine green (ICG) are often added to solders to enhance light absorption. The purpose of this in vitro study was to examine the impact of different parameters of laser soldering on the thermo-physical properties of the skin. A mixture of albumin solder and ICG was prepared, and then the coated samples were irradiated by an 810 nm diode laser under different conditions. The temperature rise, number of scans (N(s)), and scan velocity (V(s)) were investigated in this study. The results showed that, at each laser irradiance (I), the tensile strength (sigma) of incisions repaired in static mode was higher than in dynamic mode and that the sigma increased with both increasing N(s) and increasing I. It is therefore important to consider the trade off between scan velocity and surface temperature for achieving an optimum operating condition.