SIVAKUMAR MANICKAM - Academia.edu (original) (raw)
Papers by SIVAKUMAR MANICKAM
Catalysts
In the chemical industry, 1,4-diethylene dioxide, commonly called dioxane, is widely used as a so... more In the chemical industry, 1,4-diethylene dioxide, commonly called dioxane, is widely used as a solvent as well as a stabilizing agent for chlorinated solvents. Due to its high miscibility, dioxane is a ubiquitous water contaminant. This study investigates the effectiveness of catalyst- and ultrasound (US)-assisted persulfate (PS) activation with regard to degrading dioxane. As a first step, a composite catalyst was prepared using zeolite. A sonochemical dispersion and reduction method was used to dope zeolite with iron nanoparticles (FeNP/Z). In the subsequent study, the reaction kinetics of dioxane degradation following the single-stage and two-stage addition of PS was examined in the presence of a catalyst. Using GC-MS analysis, intermediate compounds formed from dioxane degradation were identified, and plausible reaction pathways were described. Upon 120 min of sonication in the presence of a catalyst with a two-stage injection of PS, 95% 100 mg/L dioxane was degraded. Finally, t...
Pharmaceutics
The delivery of drugs via transdermal routes is an attractive approach due to ease of administrat... more The delivery of drugs via transdermal routes is an attractive approach due to ease of administration, bypassing of the first-pass metabolism, and the large skin surface area. However, a major drawback is an inability to surmount the skin’s stratum corneum (SC) layer. Therefore, techniques reversibly modifying the stratum corneum have been a classical approach. Surmounting the significant barrier properties of the skin in a well-organised, momentary, and harmless approach is still challenging. Chemical permeation enhancers (CPEs) with higher activity are associated with certain side effects restricting their advancement in transdermal drug delivery. Furthermore, complexity in the interaction of CPEs with the skin has led to difficulty in elucidating the mechanism of action. Nevertheless, CPEs-aided transdermal drug delivery will accomplish its full potential due to advancements in analytical techniques, synthetic chemistry, and combinatorial studies. This review focused on techniques...
Evidence-Based Complementary and Alternative Medicine
Fresh fruit and vegetables are highly utilized commodities by health-conscious consumers and repr... more Fresh fruit and vegetables are highly utilized commodities by health-conscious consumers and represent a prominent segment in the functional and nutritional food sector. However, food processing is causing significant loss of nutritional components, and the generation of waste is creating serious economic and environmental problems. Fruit and vegetables encompass husk, peels, pods, pomace, seeds, and stems, which are usually discarded, despite being known to contain potentially beneficial compounds, such as carotenoids, dietary fibers, enzymes, and polyphenols. The emerging interest in the food industry in the nutritional and biofunctional constituents of polyphenols has prompted the utilization of fruit and vegetable waste for developing enriched and functional foods, with applications in the pharmaceutical industry. Moreover, the utilization of waste for developing diverse and crucial bioactive commodities is a fundamental step in sustainable development. Furthermore, it provides ...
Catalysts
This study effectively demonstrates the sonochemical synthesis of visible-light-responsive Cu-ZnO... more This study effectively demonstrates the sonochemical synthesis of visible-light-responsive Cu-ZnO/TiO2 ternary Z-scheme heterojunction nanocomposite photocatalyst. The as-prepared photocatalyst was comprehensively characterized by techniques including high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray analysis (EDX) and elemental dot mapping, X-ray diffraction (XRD), UV-Vis-diffuse reflectance spectroscopy (UV-Vis-DRS), Brunauer–Emmett–Teller (BET) surface area, and Fourier-transform infrared spectroscopy (FTIR). The photocatalytic activity of the Cu-ZnO/TiO2 nanocomposite photocatalyst was assessed for the degradation of Congo red (CR), an azo dye, under direct sunlight. The pseudo-first-order rate constant for CR degradation was found to be 0.09 min−1. The outcome implies that the synthesised nanocomposite photocatalyst demonstrates excellent photocatalytic activity under direct sunlight as 98...
In the present study, an intensified approach for the synthesis of starch nanoparticles (SNPs) wa... more In the present study, an intensified approach for the synthesis of starch nanoparticles (SNPs) was demonstrated by using ultrasound-assisted acid hydrolysis method. The conventional acid hydrolysis for the synthesis of SNPs was intensified using ultrasound. The overall time required to convert starch granules to SNPs in the conventional acid hydrolysis method (48 h) was significantly reduced to 45 min by simultaneous acid hydrolysis and ultrasound irradiation. The acid concentration was found to be an important parameter for obtaining the desired size and morphology of the synthesized SNPs. The variation in the surface charges associated with the SNPs was confirmed through measuring their zeta potential. These potential charges on the surface of SNPs induce crystal growth among the synthesized nanoparticles. The irregular crystal morphology at higher acid concentration clearly shows SNPs' attachment with each other by coalescence. The higher crystallinity for SNPs was observed a...
Catalysts
Catalysts increase reaction rates; however, the surface area to volume ratio of catalysts has a v... more Catalysts increase reaction rates; however, the surface area to volume ratio of catalysts has a vital role in catalytic activity. The noble metals such as platinum (Pt) and gold (Au) are expensive; despite this, they have proven their existence in catalysis, motivating the synthesis of supported metal catalysts. Metal catalysts need to be highly dispersed onto the support. In this investigation, an ultrasound approach has been attempted to synthesise highly photoactive titanium dioxide (TiO2) nanoparticles by the hydrolysis of titanium tetraisopropoxide in an acetone/methanol mixture. To enhance its photocatalytic activity, TiO2 was doped with Pt. The synthesised photocatalyst was characterised by techniques such as particle size analysis (PSA), XRD, FE-SEM, TEM, and EDX. The enhancement in the surface characteristics of Pt-doped TiO2 compared with bare TiO2 support was confirmed with Brunauer–Emmett–Teller (BET) analysis. The enhanced surface area and uniformity in particle size di...
Nanomaterials, 2021
The detection of cancer biomarkers in the early stages could prevent cancer-related deaths signif... more The detection of cancer biomarkers in the early stages could prevent cancer-related deaths significantly. Nanomaterials combined with biomolecules are extensively used in drug delivery, imaging, and sensing applications by targeting the overexpressed cancer proteins such as folate receptors (FRs) to control the disease by providing earlier treatments. In this investigation, biocompatible reduced graphene oxide (rGO) nanosheets combined with folic acid (FA)-a vitamin with high bioaffinity to FRs-is utilized to develop an electrochemical sensor for cancer detection. To mimic the cancer cell environment, FR-β protein is used to evaluate the response of the rGO-FA sensor. The formation of the rGO-FA nanocomposite was confirmed through various characterization techniques. A glassy carbon (GC) electrode was then modified with the obtained rGO-FA and analyzed via differential pulse voltammetry (DPV) for its specific detection towards FRs. Using the DPV technique, the rGO-FA-modified electr...
RSC Advances, 2020
C. roseus phytochemicals are physisorbed on the 111 Fe surface, and the oxygen non-bonding electr... more C. roseus phytochemicals are physisorbed on the 111 Fe surface, and the oxygen non-bonding electron chemisorbed on the polarized state 111 Fe surface.
A wide variety of bacteria are found to be the tiny factories in the production of polyhydroxyalk... more A wide variety of bacteria are found to be the tiny factories in the production of polyhydroxyalkanoate (PHA) biopolymer. PHA is the polyesters of 3-hydroxyalkanoic acids which occur in bacteria when the bacteria is subjected to nutrient limitation and simultaneously fed with an excess amount of carbon. This unfavorable condition forces the bacteria to store carbon in the form of resorbable cellular inclusions called PHA. Biosynthesized PHA has the ability to replace the currently feasible harmful petroleum based plastics to biobased plastics. PHA research is being focused mainly on two facts - bulk production of environment friendly low-cost PHA and functional group modification for multiple applications to mankind. Many companies are already producing PHA with highly tunable properties and are looking into economically feasible technologies for mass production of PHA. The core focus of PHA research includes a selection of potential PHA producers and low to zero cost carbon sources...
DESALINATION AND WATER TREATMENT, 2017
Treatment of Palm Oil Mill Effluent (POME) after the anaerobic digestion process has been carried... more Treatment of Palm Oil Mill Effluent (POME) after the anaerobic digestion process has been carried out using biochar as an adsorbent to reduce its initial color intensity, and the total suspended solids (TSS). Biochars derived from empty oil palm fruit bunches (EFBs) were produced through pyrolysis at 700°C. About 95% color reduction and 100% TSS removal were observed after 24 h of contact time with 5 g biochar/50 ml POME. It has been observed that the pH and the duration of treatment played an important role in the adsorption process. The equilibrium adsorption data were best represented by the Langmuir isotherm. The kinetics of adsorption of suspended solids and color on the biochars were found to correlate with the pseudo-second-order model, with a correlation coefficient of R 2 > 0.99. Considering the high efficiency of the adsorbent in decreasing the color and TSS concentration, the EFB-based biosorbent is an environmentally-friendly biomass material that may be encouraged for use in waste management for resource and reuse.
![Research paper thumbnail of Hydration or hydroxylation: direct synthesis of fullerenol from pristine fullerene [C60] via acoustic cavitation in the presence of hydrogen peroxide](https://attachments.academia-assets.com/110776746/thumbnails/1.jpg)
](RSC Advances, 2017
A green low energy approach avoiding the use of toxic or corrosive reagents/solvents is proposed ... more A green low energy approach avoiding the use of toxic or corrosive reagents/solvents is proposed for the synthesis of potential fullerenol moieties [C60(OH)n·mH2O], in which C60 in dil. H2O2 (30%) aqueous media was ultrasonicated (20 kHz, 200 W) at 30% amplitude for 1 h.
Scientific Reports, 2016
Metastasis of lung carcinoma to breast and vice versa accounts for one of the vast majority of ca... more Metastasis of lung carcinoma to breast and vice versa accounts for one of the vast majority of cancer deaths. Synergistic treatments are proven to be the effective method to inhibit malignant cell proliferation. It is highly advantageous to use the minimum amount of a potent toxic drug, such as paclitaxel (Ptx) in ng/ml together with a natural and safe anticancer drug, curcumin (Cur) to reduce the systemic toxicity. However, both Cur and Ptx suffer from poor bioavailability. Herein, a drug delivery cargo was engineered by functionalizing reduced graphene oxide (G) with an amphiphilic polymer, PF-127 (P) by hydrophobic assembly. The drugs were loaded via pi-pi interactions, resulting in a nano-sized GP-Cur-Ptx of 140 nm. A remarkably high Cur loading of 678 wt.% was achieved, the highest thus far compared to any other Cur nanoformulations. Based on cell proliferation assay, GP-Cur-Ptx is a synergistic treatment (CI < 1) and is highly potent towards lung, A549 (IC50 = 13.24 μg/ml) ...
International Journal of Nanomedicine, 2016
The high aspect ratio of carbon nanotubes (CNTs) allows the attachment of compounds that enhance ... more The high aspect ratio of carbon nanotubes (CNTs) allows the attachment of compounds that enhance the functionality of the drug vehicle. Considering this, use of CNTs as a multifunctional insulin carrier may be an interesting prospect to explore. Materials and methods: The carboxylic acid groups were functionalized on the sidewalls of single-walled CNTs (SWCNTs) followed by diimidation to form amide bonds with the amine groups of the insulin. Results: Scanning transmission electron microscopy and transmission electron microscopy establish clear conjugation of insulin onto the surface of nanotube sidewalls. The incorporation of insulin further increased the solubility of SWCNTs in biological solution for the tested period of 5 months. Bicinchoninic acid assay confirms that 0.42 mg of insulin could be attached to every 1 mg of carboxylated SWCNTs. Conclusion: With the successful conjugation of insulin to SWCNTs, it opens up the potential use of SWCNTs as an insulin carrier which in need of further biological studies.
Ultrasonics Sonochemistry, 2017
Coupling multiple frequencies in ultrasonic systems is one of the highly desired area of research... more Coupling multiple frequencies in ultrasonic systems is one of the highly desired area of research for sonochemists, as it is known for producing synergistic effects on various ultrasonic reactions. In this study, the characteristics of a hexagonal-shaped triple frequency ultrasonic reactor with the combination frequencies of 28, 40 and 70 kHz were studied. The results showed that uniform temperature increment was achieved throughout the reactor at all frequency combinations. On the other hand, sonochemiluminescence emission and degradation rate of Rhodamine B varies throughout different areas of the reactor, indicating the presence of acoustic 'hot spots' at certain areas of the reactor. Also, coupling dual and triple frequencies showed a decrease in the hydroxyl radical (Å OH) production, suggesting probable wave cancelling effect in the system. The results can therefore be served as a guide to optimize the usage of a triple frequency ultrasonic reactor for future applications.
Clean Technologies and Environmental Policy, 2015
Highlights An eco-friendly green processing method for Anaerobically digested POME treatment ha... more Highlights An eco-friendly green processing method for Anaerobically digested POME treatment has been investigated. Combined chitosan coagulation with AOPs was utilised. Higher COD (82.82±1.71%) removal for chitosan/H2O2 compared to chitosan-Fenton oxidation was observed. Chitosan-Fenton oxidation was found to be favourable for higher TSS removal but not for COD removal. Comparison of performance with other technologies has been reported with economic analysis. Research significance Industrial wastewater treatment exploiting advanced oxidation processes (AOPs) involves generation of hydroxyl radicals (OH .) to degrade the organic components and is a well-documented approach. In the present study, natural biomaterial Chitosan as a coagulant combined with various AOP's have been investigated for the anaerobically digested palm oil mill effluent (AAD-POME) treatment. Research investigations to-date on the post-treatment of POME is very limited and the lacking of lab-scale study could be the major reason for the failing industrial plant trials. Hence the current study explores the possibility and reports in detail on an alternative eco-friendly green processing technique for POME treatment. The objectives of present investigation focuses on the post-treatment of AAD-POME primarily by coagulation using (a) chitosan (b) chitosan with FeSO4 (c) chitosan with H2O2 and (d) chitosan with Fenton oxidation. The results conclude that chitosan with H2O2 proved to be the most promising alternative for POME treatment compared to chitosan with Fenton oxidation.
Journal of Cleaner Production, 2016
This investigation focuses on activated carbon (AC) adsorption and ultrasound (US) cavitation for... more This investigation focuses on activated carbon (AC) adsorption and ultrasound (US) cavitation for polishing the palm oil mill effluent (POME). Both AC adsorption and US cavitation were investigated individually, in series and operating them in a combined way. The efficiency of above processes has been evaluated in terms of removal of chemical oxygen demand (COD) and total suspended solids (TSS). For the individual operation, the optimisation studies were carried out by using the following conditions: AC dosage (50-200 g/L); contact time (2, 4, 6 h); US power amplitude (50% and 80%) and US cavitation time (30-180 min). The optimisation studies utilising US power amplitude (50%) and cavitation time (15 min) followed by AC adsorption using minimum AC dosage (50 g/L) and contact time (30 min) resulted in ~100% COD and 83.33 % TSS removals which meets the discharge limits set by the Department of Environment (DoE), Malaysia. The hybrid operation was also studied by simultaneously employing AC adsorption and US cavitation and it was observed that an adsorption dosage of 50 g /L resulted into achieving 73.08 % COD and 98.33 % TSS removals within 15 min of US irradiation. With the possibility of continuous and feasible sonochemical reactors, this hybrid approach of US cavitation followed by AC adsorption could be an alternative processing technique for POME polishing.
International Journal of Nanomedicine, 2015
Purpose: A simple, one-pot strategy was used to synthesize reduced graphene oxide (RGO) nanosheet... more Purpose: A simple, one-pot strategy was used to synthesize reduced graphene oxide (RGO) nanosheets by utilizing an easily available over-the-counter medicinal and edible mushroom, Ganoderma lucidum. Methods: The mushroom was boiled in hot water to liberate the polysaccharides, the extract of which was then used directly for the reduction of graphene oxide. The abundance of polysaccharides present in the mushroom serves as a good reducing agent. The proposed strategy evades the use of harmful and expensive chemicals and avoids the typical tedious reaction methods. Results: More importantly, the mushroom extract can be easily separated from the product without generating any residual byproducts and can be reused at least three times with good conversion efficiency (75%). It was readily dispersible in water without the need of ultrasonication or any surfactants; whereas 5 minutes of ultrasonication with various solvents produced RGO which was stable for the tested period of 1 year. Based on electrochemical measurements, the followed method did not jeopardize RGO's electrical conductivity. Moreover, the obtained RGO was highly biocompatible to not only colon (HT-29) and brain (U87MG) cancer cells, but was also viable towards normal cells (MRC-5). Conclusion: Besides being eco-friendly, this mushroom based approach is easily scalable and demonstrates remarkable RGO stability and biocompatibility, even without any form of functionalization.
Journal of Nanoscience and Nanotechnology, 2006
Solid Lipid Nanoparticles (SLN) containing Methotrexate (MTX), an anticancer drug for intravenous... more Solid Lipid Nanoparticles (SLN) containing Methotrexate (MTX), an anticancer drug for intravenous administration was formulated and characterized. The SLN dispersions with MTX, stearic acid, and soya lecithin in the ratio of 1:4:1, 1:4:1.5, and 1:4:2, sodium taurodeoxycholate and distilled water were prepared by micro emulsification solidification method. The results show that the prepared MTX-SLN particles (with MTX–Stearic acid–Soya lecithin—1:4:2) have an average size of 270 nm with 51.3% drug entrapment. The in vitro-release was attained up to 15th h. The pharmacokinetic studyreveals that the half-life and MRT of SLNs were higher than MTX solution. The life span of EAC (Ehrlich Ascite Carcinoma) bearing mice was increased when treated with MTX-SLNs (Methotrexate nanoparticles). These results clearly indicate that SLNs are a promising sustained release drug targeting system for lipophilic antitumour drugs.
Journal of Nanobiotechnology, 2014
Journal of Magnetism and Magnetic Materials, 2004
A fine strontium hexaferrite powder has been successfully synthesized by a sonochemical method em... more A fine strontium hexaferrite powder has been successfully synthesized by a sonochemical method employing Fe(CO) 5 and SrCO 3 . SrCO 3 was first synthesized using strontium nitrate and urea, and it was found that applying ultrasound radiation during this process results in the ...
Catalysts
In the chemical industry, 1,4-diethylene dioxide, commonly called dioxane, is widely used as a so... more In the chemical industry, 1,4-diethylene dioxide, commonly called dioxane, is widely used as a solvent as well as a stabilizing agent for chlorinated solvents. Due to its high miscibility, dioxane is a ubiquitous water contaminant. This study investigates the effectiveness of catalyst- and ultrasound (US)-assisted persulfate (PS) activation with regard to degrading dioxane. As a first step, a composite catalyst was prepared using zeolite. A sonochemical dispersion and reduction method was used to dope zeolite with iron nanoparticles (FeNP/Z). In the subsequent study, the reaction kinetics of dioxane degradation following the single-stage and two-stage addition of PS was examined in the presence of a catalyst. Using GC-MS analysis, intermediate compounds formed from dioxane degradation were identified, and plausible reaction pathways were described. Upon 120 min of sonication in the presence of a catalyst with a two-stage injection of PS, 95% 100 mg/L dioxane was degraded. Finally, t...
Pharmaceutics
The delivery of drugs via transdermal routes is an attractive approach due to ease of administrat... more The delivery of drugs via transdermal routes is an attractive approach due to ease of administration, bypassing of the first-pass metabolism, and the large skin surface area. However, a major drawback is an inability to surmount the skin’s stratum corneum (SC) layer. Therefore, techniques reversibly modifying the stratum corneum have been a classical approach. Surmounting the significant barrier properties of the skin in a well-organised, momentary, and harmless approach is still challenging. Chemical permeation enhancers (CPEs) with higher activity are associated with certain side effects restricting their advancement in transdermal drug delivery. Furthermore, complexity in the interaction of CPEs with the skin has led to difficulty in elucidating the mechanism of action. Nevertheless, CPEs-aided transdermal drug delivery will accomplish its full potential due to advancements in analytical techniques, synthetic chemistry, and combinatorial studies. This review focused on techniques...
Evidence-Based Complementary and Alternative Medicine
Fresh fruit and vegetables are highly utilized commodities by health-conscious consumers and repr... more Fresh fruit and vegetables are highly utilized commodities by health-conscious consumers and represent a prominent segment in the functional and nutritional food sector. However, food processing is causing significant loss of nutritional components, and the generation of waste is creating serious economic and environmental problems. Fruit and vegetables encompass husk, peels, pods, pomace, seeds, and stems, which are usually discarded, despite being known to contain potentially beneficial compounds, such as carotenoids, dietary fibers, enzymes, and polyphenols. The emerging interest in the food industry in the nutritional and biofunctional constituents of polyphenols has prompted the utilization of fruit and vegetable waste for developing enriched and functional foods, with applications in the pharmaceutical industry. Moreover, the utilization of waste for developing diverse and crucial bioactive commodities is a fundamental step in sustainable development. Furthermore, it provides ...
Catalysts
This study effectively demonstrates the sonochemical synthesis of visible-light-responsive Cu-ZnO... more This study effectively demonstrates the sonochemical synthesis of visible-light-responsive Cu-ZnO/TiO2 ternary Z-scheme heterojunction nanocomposite photocatalyst. The as-prepared photocatalyst was comprehensively characterized by techniques including high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray analysis (EDX) and elemental dot mapping, X-ray diffraction (XRD), UV-Vis-diffuse reflectance spectroscopy (UV-Vis-DRS), Brunauer–Emmett–Teller (BET) surface area, and Fourier-transform infrared spectroscopy (FTIR). The photocatalytic activity of the Cu-ZnO/TiO2 nanocomposite photocatalyst was assessed for the degradation of Congo red (CR), an azo dye, under direct sunlight. The pseudo-first-order rate constant for CR degradation was found to be 0.09 min−1. The outcome implies that the synthesised nanocomposite photocatalyst demonstrates excellent photocatalytic activity under direct sunlight as 98...
In the present study, an intensified approach for the synthesis of starch nanoparticles (SNPs) wa... more In the present study, an intensified approach for the synthesis of starch nanoparticles (SNPs) was demonstrated by using ultrasound-assisted acid hydrolysis method. The conventional acid hydrolysis for the synthesis of SNPs was intensified using ultrasound. The overall time required to convert starch granules to SNPs in the conventional acid hydrolysis method (48 h) was significantly reduced to 45 min by simultaneous acid hydrolysis and ultrasound irradiation. The acid concentration was found to be an important parameter for obtaining the desired size and morphology of the synthesized SNPs. The variation in the surface charges associated with the SNPs was confirmed through measuring their zeta potential. These potential charges on the surface of SNPs induce crystal growth among the synthesized nanoparticles. The irregular crystal morphology at higher acid concentration clearly shows SNPs' attachment with each other by coalescence. The higher crystallinity for SNPs was observed a...
Catalysts
Catalysts increase reaction rates; however, the surface area to volume ratio of catalysts has a v... more Catalysts increase reaction rates; however, the surface area to volume ratio of catalysts has a vital role in catalytic activity. The noble metals such as platinum (Pt) and gold (Au) are expensive; despite this, they have proven their existence in catalysis, motivating the synthesis of supported metal catalysts. Metal catalysts need to be highly dispersed onto the support. In this investigation, an ultrasound approach has been attempted to synthesise highly photoactive titanium dioxide (TiO2) nanoparticles by the hydrolysis of titanium tetraisopropoxide in an acetone/methanol mixture. To enhance its photocatalytic activity, TiO2 was doped with Pt. The synthesised photocatalyst was characterised by techniques such as particle size analysis (PSA), XRD, FE-SEM, TEM, and EDX. The enhancement in the surface characteristics of Pt-doped TiO2 compared with bare TiO2 support was confirmed with Brunauer–Emmett–Teller (BET) analysis. The enhanced surface area and uniformity in particle size di...
Nanomaterials, 2021
The detection of cancer biomarkers in the early stages could prevent cancer-related deaths signif... more The detection of cancer biomarkers in the early stages could prevent cancer-related deaths significantly. Nanomaterials combined with biomolecules are extensively used in drug delivery, imaging, and sensing applications by targeting the overexpressed cancer proteins such as folate receptors (FRs) to control the disease by providing earlier treatments. In this investigation, biocompatible reduced graphene oxide (rGO) nanosheets combined with folic acid (FA)-a vitamin with high bioaffinity to FRs-is utilized to develop an electrochemical sensor for cancer detection. To mimic the cancer cell environment, FR-β protein is used to evaluate the response of the rGO-FA sensor. The formation of the rGO-FA nanocomposite was confirmed through various characterization techniques. A glassy carbon (GC) electrode was then modified with the obtained rGO-FA and analyzed via differential pulse voltammetry (DPV) for its specific detection towards FRs. Using the DPV technique, the rGO-FA-modified electr...
RSC Advances, 2020
C. roseus phytochemicals are physisorbed on the 111 Fe surface, and the oxygen non-bonding electr... more C. roseus phytochemicals are physisorbed on the 111 Fe surface, and the oxygen non-bonding electron chemisorbed on the polarized state 111 Fe surface.
A wide variety of bacteria are found to be the tiny factories in the production of polyhydroxyalk... more A wide variety of bacteria are found to be the tiny factories in the production of polyhydroxyalkanoate (PHA) biopolymer. PHA is the polyesters of 3-hydroxyalkanoic acids which occur in bacteria when the bacteria is subjected to nutrient limitation and simultaneously fed with an excess amount of carbon. This unfavorable condition forces the bacteria to store carbon in the form of resorbable cellular inclusions called PHA. Biosynthesized PHA has the ability to replace the currently feasible harmful petroleum based plastics to biobased plastics. PHA research is being focused mainly on two facts - bulk production of environment friendly low-cost PHA and functional group modification for multiple applications to mankind. Many companies are already producing PHA with highly tunable properties and are looking into economically feasible technologies for mass production of PHA. The core focus of PHA research includes a selection of potential PHA producers and low to zero cost carbon sources...
DESALINATION AND WATER TREATMENT, 2017
Treatment of Palm Oil Mill Effluent (POME) after the anaerobic digestion process has been carried... more Treatment of Palm Oil Mill Effluent (POME) after the anaerobic digestion process has been carried out using biochar as an adsorbent to reduce its initial color intensity, and the total suspended solids (TSS). Biochars derived from empty oil palm fruit bunches (EFBs) were produced through pyrolysis at 700°C. About 95% color reduction and 100% TSS removal were observed after 24 h of contact time with 5 g biochar/50 ml POME. It has been observed that the pH and the duration of treatment played an important role in the adsorption process. The equilibrium adsorption data were best represented by the Langmuir isotherm. The kinetics of adsorption of suspended solids and color on the biochars were found to correlate with the pseudo-second-order model, with a correlation coefficient of R 2 > 0.99. Considering the high efficiency of the adsorbent in decreasing the color and TSS concentration, the EFB-based biosorbent is an environmentally-friendly biomass material that may be encouraged for use in waste management for resource and reuse.
RSC Advances, 2017
A green low energy approach avoiding the use of toxic or corrosive reagents/solvents is proposed ... more A green low energy approach avoiding the use of toxic or corrosive reagents/solvents is proposed for the synthesis of potential fullerenol moieties [C60(OH)n·mH2O], in which C60 in dil. H2O2 (30%) aqueous media was ultrasonicated (20 kHz, 200 W) at 30% amplitude for 1 h.
Scientific Reports, 2016
Metastasis of lung carcinoma to breast and vice versa accounts for one of the vast majority of ca... more Metastasis of lung carcinoma to breast and vice versa accounts for one of the vast majority of cancer deaths. Synergistic treatments are proven to be the effective method to inhibit malignant cell proliferation. It is highly advantageous to use the minimum amount of a potent toxic drug, such as paclitaxel (Ptx) in ng/ml together with a natural and safe anticancer drug, curcumin (Cur) to reduce the systemic toxicity. However, both Cur and Ptx suffer from poor bioavailability. Herein, a drug delivery cargo was engineered by functionalizing reduced graphene oxide (G) with an amphiphilic polymer, PF-127 (P) by hydrophobic assembly. The drugs were loaded via pi-pi interactions, resulting in a nano-sized GP-Cur-Ptx of 140 nm. A remarkably high Cur loading of 678 wt.% was achieved, the highest thus far compared to any other Cur nanoformulations. Based on cell proliferation assay, GP-Cur-Ptx is a synergistic treatment (CI < 1) and is highly potent towards lung, A549 (IC50 = 13.24 μg/ml) ...
International Journal of Nanomedicine, 2016
The high aspect ratio of carbon nanotubes (CNTs) allows the attachment of compounds that enhance ... more The high aspect ratio of carbon nanotubes (CNTs) allows the attachment of compounds that enhance the functionality of the drug vehicle. Considering this, use of CNTs as a multifunctional insulin carrier may be an interesting prospect to explore. Materials and methods: The carboxylic acid groups were functionalized on the sidewalls of single-walled CNTs (SWCNTs) followed by diimidation to form amide bonds with the amine groups of the insulin. Results: Scanning transmission electron microscopy and transmission electron microscopy establish clear conjugation of insulin onto the surface of nanotube sidewalls. The incorporation of insulin further increased the solubility of SWCNTs in biological solution for the tested period of 5 months. Bicinchoninic acid assay confirms that 0.42 mg of insulin could be attached to every 1 mg of carboxylated SWCNTs. Conclusion: With the successful conjugation of insulin to SWCNTs, it opens up the potential use of SWCNTs as an insulin carrier which in need of further biological studies.
Ultrasonics Sonochemistry, 2017
Coupling multiple frequencies in ultrasonic systems is one of the highly desired area of research... more Coupling multiple frequencies in ultrasonic systems is one of the highly desired area of research for sonochemists, as it is known for producing synergistic effects on various ultrasonic reactions. In this study, the characteristics of a hexagonal-shaped triple frequency ultrasonic reactor with the combination frequencies of 28, 40 and 70 kHz were studied. The results showed that uniform temperature increment was achieved throughout the reactor at all frequency combinations. On the other hand, sonochemiluminescence emission and degradation rate of Rhodamine B varies throughout different areas of the reactor, indicating the presence of acoustic 'hot spots' at certain areas of the reactor. Also, coupling dual and triple frequencies showed a decrease in the hydroxyl radical (Å OH) production, suggesting probable wave cancelling effect in the system. The results can therefore be served as a guide to optimize the usage of a triple frequency ultrasonic reactor for future applications.
Clean Technologies and Environmental Policy, 2015
Highlights An eco-friendly green processing method for Anaerobically digested POME treatment ha... more Highlights An eco-friendly green processing method for Anaerobically digested POME treatment has been investigated. Combined chitosan coagulation with AOPs was utilised. Higher COD (82.82±1.71%) removal for chitosan/H2O2 compared to chitosan-Fenton oxidation was observed. Chitosan-Fenton oxidation was found to be favourable for higher TSS removal but not for COD removal. Comparison of performance with other technologies has been reported with economic analysis. Research significance Industrial wastewater treatment exploiting advanced oxidation processes (AOPs) involves generation of hydroxyl radicals (OH .) to degrade the organic components and is a well-documented approach. In the present study, natural biomaterial Chitosan as a coagulant combined with various AOP's have been investigated for the anaerobically digested palm oil mill effluent (AAD-POME) treatment. Research investigations to-date on the post-treatment of POME is very limited and the lacking of lab-scale study could be the major reason for the failing industrial plant trials. Hence the current study explores the possibility and reports in detail on an alternative eco-friendly green processing technique for POME treatment. The objectives of present investigation focuses on the post-treatment of AAD-POME primarily by coagulation using (a) chitosan (b) chitosan with FeSO4 (c) chitosan with H2O2 and (d) chitosan with Fenton oxidation. The results conclude that chitosan with H2O2 proved to be the most promising alternative for POME treatment compared to chitosan with Fenton oxidation.
Journal of Cleaner Production, 2016
This investigation focuses on activated carbon (AC) adsorption and ultrasound (US) cavitation for... more This investigation focuses on activated carbon (AC) adsorption and ultrasound (US) cavitation for polishing the palm oil mill effluent (POME). Both AC adsorption and US cavitation were investigated individually, in series and operating them in a combined way. The efficiency of above processes has been evaluated in terms of removal of chemical oxygen demand (COD) and total suspended solids (TSS). For the individual operation, the optimisation studies were carried out by using the following conditions: AC dosage (50-200 g/L); contact time (2, 4, 6 h); US power amplitude (50% and 80%) and US cavitation time (30-180 min). The optimisation studies utilising US power amplitude (50%) and cavitation time (15 min) followed by AC adsorption using minimum AC dosage (50 g/L) and contact time (30 min) resulted in ~100% COD and 83.33 % TSS removals which meets the discharge limits set by the Department of Environment (DoE), Malaysia. The hybrid operation was also studied by simultaneously employing AC adsorption and US cavitation and it was observed that an adsorption dosage of 50 g /L resulted into achieving 73.08 % COD and 98.33 % TSS removals within 15 min of US irradiation. With the possibility of continuous and feasible sonochemical reactors, this hybrid approach of US cavitation followed by AC adsorption could be an alternative processing technique for POME polishing.
International Journal of Nanomedicine, 2015
Purpose: A simple, one-pot strategy was used to synthesize reduced graphene oxide (RGO) nanosheet... more Purpose: A simple, one-pot strategy was used to synthesize reduced graphene oxide (RGO) nanosheets by utilizing an easily available over-the-counter medicinal and edible mushroom, Ganoderma lucidum. Methods: The mushroom was boiled in hot water to liberate the polysaccharides, the extract of which was then used directly for the reduction of graphene oxide. The abundance of polysaccharides present in the mushroom serves as a good reducing agent. The proposed strategy evades the use of harmful and expensive chemicals and avoids the typical tedious reaction methods. Results: More importantly, the mushroom extract can be easily separated from the product without generating any residual byproducts and can be reused at least three times with good conversion efficiency (75%). It was readily dispersible in water without the need of ultrasonication or any surfactants; whereas 5 minutes of ultrasonication with various solvents produced RGO which was stable for the tested period of 1 year. Based on electrochemical measurements, the followed method did not jeopardize RGO's electrical conductivity. Moreover, the obtained RGO was highly biocompatible to not only colon (HT-29) and brain (U87MG) cancer cells, but was also viable towards normal cells (MRC-5). Conclusion: Besides being eco-friendly, this mushroom based approach is easily scalable and demonstrates remarkable RGO stability and biocompatibility, even without any form of functionalization.
Journal of Nanoscience and Nanotechnology, 2006
Solid Lipid Nanoparticles (SLN) containing Methotrexate (MTX), an anticancer drug for intravenous... more Solid Lipid Nanoparticles (SLN) containing Methotrexate (MTX), an anticancer drug for intravenous administration was formulated and characterized. The SLN dispersions with MTX, stearic acid, and soya lecithin in the ratio of 1:4:1, 1:4:1.5, and 1:4:2, sodium taurodeoxycholate and distilled water were prepared by micro emulsification solidification method. The results show that the prepared MTX-SLN particles (with MTX–Stearic acid–Soya lecithin—1:4:2) have an average size of 270 nm with 51.3% drug entrapment. The in vitro-release was attained up to 15th h. The pharmacokinetic studyreveals that the half-life and MRT of SLNs were higher than MTX solution. The life span of EAC (Ehrlich Ascite Carcinoma) bearing mice was increased when treated with MTX-SLNs (Methotrexate nanoparticles). These results clearly indicate that SLNs are a promising sustained release drug targeting system for lipophilic antitumour drugs.
Journal of Nanobiotechnology, 2014
Journal of Magnetism and Magnetic Materials, 2004
A fine strontium hexaferrite powder has been successfully synthesized by a sonochemical method em... more A fine strontium hexaferrite powder has been successfully synthesized by a sonochemical method employing Fe(CO) 5 and SrCO 3 . SrCO 3 was first synthesized using strontium nitrate and urea, and it was found that applying ultrasound radiation during this process results in the ...