In this study, a wound dressing based on polyurethane (PU) blended with copper sulphate nanofibers was developed using an electrospinning technique. The prepared PU and PU nanocomposites showed smooth fibers without any bead defects. The prepared nanocomposites showed smaller fiber (663 ± 156.30 nm) and pore (888 ± 70.93 nm) diameter compared to the pristine PU (fiber diameter 1159 ± 147.48 nm and pore diameter 1087 ± 62.51 nm). The interaction of PU with copper sulphate was evident in the infrared spectrum through hydrogen-bond formation. Thermal analysis displayed enhanced weight residue at higher temperature suggesting interaction of PU with copper sulphate. The contact angle measurements revealed the hydrophilic nature of the prepared nanocomposites (71° ± 2.309°) compared with pure PU (100° ± 0.5774°). The addition of copper sulphate into the PU matrix increased the surface roughness, as revealed in the atomic force microscopy (AFM) analysis. Mechanical testing demonstrated the enhanced tensile strength behavior of the fabricated nanocomposites (18.58 MPa) compared with the pristine PU (7.12 MPa). The coagulation assays indicated the enhanced blood compatibility of the developed nanocomposites [activated partial thromboplastin time (APTT)-179 ± 3.606 s and partial thromboplastin time (PT)-105 ± 2.646 s] by showing a prolonged blood clotting time compared with the pristine PU (APTT-147.7 ± 3.512 s and PT-84.67 ± 2.517 s). Furthermore, the hemolysis and cytotoxicity studies suggested a less toxicity nature of prepared nanocomposites by displaying low hemolytic index and enhanced cell viability rates compared with the PU membrane. It was observed that the fabricated novel wound dressing possesses better physicochemical and enhanced blood compatibility properties, and may be utilized for wound-healing applications.
The use of nanometal oxides in nanoagronomy has garnered considerable attention due to their excellent antifungal and plant growth promotion properties. Hybrid nanometal oxides, which combine the strengths of individual nanomaterials, have emerged as a promising class of materials. In this study, nanomagnesium oxide (n-MgO) and hybrid magnetic nanomagnesium oxide (m/n-MgO) were successfully synthesized via the ultrasound-mediated sol-gel method. Characterization results, including TGA, XRD, VSM, and FTIR, confirmed the successful synthesis of m/n-MgO. Both n-MgO and m/n-MgO underwent antifungal assays and plant growth promotion ability studies, benchmarked against the conventional fungicide-copper oxychloride. This study bridges a significant gap by simultaneously reporting the antifungal properties of both n-MgO and m/n-MgO and their impact on plant growth. The disc diffusion assay suggested that the antifungal activity of n-MgO and m/n-MgO against F. oxysporum was inversely related to the particle size. Notably, n-MgO exhibited superior antifungal performance (lower minimum inhibitory concentration (MIC)) and sustained efficacy compared with m/n-MgO, owing to distinct antifungal mechanisms. Nanorod-shaped MgO, with a smaller size (8.24 ± 5.61 nm) and higher aspect ratio, allowed them to penetrate the fungal cell wall and cause intercellular damage. In contrast, cubical m/n-MgO, with a larger size (20.95 ± 9.99 nm) and lower aspect ratio, accumulate on the fungal cell wall surface, disrupting the wall integrity, albeit less effectively against F. oxysporum. Moreover, in plant growth promotion studies, m/n-MgO-treated samples exhibited a 15.7% stronger promotion effect compared to n-MgO at their respective MICs. In addition, both n-MgO and m/n-MgO outperformed copper oxychloride in terms of antifungal and plant growth promoting activities. Thus, m/n-MgO presents a promising alternative to conventional copper-based fungicides, offering dual functionality as a fungicide and plant growth promoter, while the study also delves into the antifungal mechanisms at the intracellular level, enhancing its novelty.
The synthesis of nanocomposite with controlled surface morphology plays a key role for pollutant removal from aqueous environments. The influence of the molecular size of the polyelectrolyte in synthesizing silica-iron oxide core-shell nanocomposite with open shell structure was investigated by using dynamic light scattering, atomic force microscopy, and quartz crystal microbalance with dissipation (QCM-D). Here, poly(diallydimethylammonium chloride) (PDDA) was used to promote the attachment of iron oxide nanoparticles (IONPs) onto the silica surface to assemble a nanocomposite with magnetic and catalytic bifunctionality. High molecular weight PDDA tended to adsorb on silica colloid, forming a more extended conformation layer than low molecular weight PDDA. Subsequent attachment of IONPs onto this extended PDDA layer was more randomly distributed, forming isolated islands with open space between them. By taking amoxicillin, an antibiotic commonly found in pharmaceutical waste, as the model system, better removal was observed for silica-iron oxide nanocomposite with a more extended open shell structure.
To overcome the critical limitations of liquid-electrolyte-based dye-sensitized solar cells, quasi-solid-state electrolytes have been explored as a means of addressing long-term device stability, albeit with comparatively low ionic conductivities and device performances. Although metal oxide additives have been shown to augment ionic conductivity, their propensity to aggregate into large crystalline particles upon high-heat annealing hinders their full potential in quasi-solid-state electrolytes. In this work, sonochemical processing has been successfully applied to generate fine Co3O4 nanoparticles that are highly dispersible in a PAN:P(VP-co-VAc) polymer-blended gel electrolyte, even after calcination. An optimized nanocomposite gel polymer electrolyte containing 3 wt % sonicated Co3O4 nanoparticles (PVVA-3) delivers the highest ionic conductivity (4.62 × 10-3 S cm-1) of the series. This property is accompanied by a 51% enhancement in the apparent diffusion coefficient of triiodide versus both unmodified and unsonicated electrolyte samples. The dye-sensitized solar cell based on PVVA-3 displays a power conversion efficiency of 6.46% under AM1.5 G, 100 mW cm-2. By identifying the optimal loading of sonochemically processed nanoparticles, we are able to generate a homogenous extended particle network that effectively mobilizes redox-active species through a highly amorphous host matrix. This effect is manifested in a selective 51% enhancement in photocurrent density (JSC = 16.2 mA cm-2) and a lowered barrier to N719 dye regeneration (RCT = 193 Ω) versus an unmodified solar cell. To the best of our knowledge, this work represents the highest known efficiency to date for dye-sensitized solar cells based on a sonicated Co3O4-modified gel polymer electrolyte. Sonochemical processing, when applied in this manner, has the potential to make meaningful contributions toward the ongoing mission to achieve the widespread exploitation of stable and low-cost dye-sensitized solar cells.
In the present study, electrochemical sensing for urea was proposed utilizing graphene-based quaternary nanocomposites YInWO4-G-SiO2 (YIWGS). These YIWGS nanocomposites were utilized due to their exceptionally delicate determination of urea with the lowest detection limit (0.01 mM). These YIWGS composites were developed through a simple self-assembly method. From physical characterization, we found that the YIWGS composites are crystalline in nature (powdered X-ray diffraction), and Fourier transform infrared (FTIR) spectroscopy analysis provided the surface functionality and bonding. Scanning electron microscopy (SEM) studies indicated the morphology characteristics of the as-synthesized composites and the high-resolution transmission electron microscopy (HRTEM) image supported the formation of cubic or hexagonal morphology of the YIW nanocomposites. The YIWGS sensor showed a great electroanalytical sensing performance of 0.07 mM urea with a sensitivity of 0.06 mA cm-2, an expansive linear range of 0.7-1.5 mM with a linear response (R2 1/4 0.99), and an eminent reaction time of around 2 s. It also displayed a good linear response toward urea with negligible interferences from normal coinciding species in urine samples.
Developing biomaterial scaffolds using tissue engineering with physical and chemical surface modification processes can improve the bioactivity and biocompatibility of the materials. The appropriate substrate and site for cell attachment are crucial in cell behavior and biological activities. Therefore, the study aims to develop a conventional electrospun nanofibrous biomaterial using reproducible surface topography, which offers beneficial effects on the cell activities of bone cells. The bioactive MgO/gC3N4 was incorporated on PAN/PEG and fabricated into a nanofibrous membrane using electrospinning. The nanocomposite uniformly distributed on the PAN/PEG nanofiber helps to increase the number of induced pores and reduce the hydrophobicity of PAN. The physiochemical characterization of prepared nanoparticles and nanofibers was carried out using FTIR, X-ray diffraction (XRD), thermogravimetry analysis (TGA), X-ray photoelectron spectroscopy (XPS), and water contact angle measurements. SEM and TEM analyses examined the nanofibrous morphology and the structure of MgO/gC3N4. In vitro studies such as on ALP activity demonstrated the membrane's ability to regenerate new bone and healing capacity. Furthermore, alizarin red staining showed the increasing ability of the cell-cell interaction and calcium content for tissue regeneration. The cytotoxicity of the prepared membrane was about 97.09% of live THP-1 cells on the surface of the MgO/gC3N4@PAN/PEG membrane evaluated using MTT dye staining. The soil burial degradation analysis exhibited that the maximum degradation occurs on the 45th day because of microbial activity. In vitro PBS degradation was observed on the 15th day after the bulk hydrolysis mechanism. Hence, on the basis of the study outcomes, we affirm that the MgO/gC3N4@PAN/PEG nanofibrous membrane can act as a potential bone regenerative substrate.
This study presents the electromagnetic (EM) characterization of a multiwalled carbon nanotubes (MWCNT)-silver nanoparticles (AgNP)-reinforced poly(vinyl alcohol) (PVA) hybrid nanocomposite fabricated via the solution mixing technique. Primarily, the structure and morphological properties of the PVA/MWCNT-AgNP hybrid nanocomposite are confirmed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The complex permittivity (ε*) and permeability (μ*), as well as the electromagnetic scattering parameters are measured using a PNA network analyzer equipped with X-band waveguide. The results showed an enhanced permittivity (ε' ≈ 25) value of the hybrid nanocomposite in the frequency range of 8-12 GHz. However, the permeability decreased to almost zero (μ' ≈ 0.4) since the inclusion of AgNP with an average particle size of 40 nm is not susceptible to magnetization and causes higher magnetic losses (tan δμ) than dielectric losses (tan δε). Remarkably, the hybrid nanocomposite reduced transmission of electromagnetic (EM) wave by nearly 60% in comparison to PVA/MWCNT. This is attributed to the enhanced absorption and reflection at the nanotubes, and metal-dielectric interfaces have induced multiple internal reflections owing to the porous structure of the nanocomposite. The prospect of the PVA/MWCNT-AgNP hybrid nanocomposite is favorable as a thin absorbing material for EM shielding applications.
Considering its excellent thermal stability, alkyl phosphonium surfactant: triisobutyl(methyl)phosphonium
(TIBMP) was used in this research as an intercalant for surface
modification of Na+-MMT via ion exchange process forming organomontmorillonite
(OMMT). The OMMT was then used as filler in poly(methyl methacrylate) (PMMA) via
melt intercalation technique. OMMT decomposed at a higher temperature than commercial
alkyammonium modified MMT. Exfoliated and intercalated types of nanocomposites
are obtained from PMMA/OMMTs at low and high content of OMMT loading, depending
on the space of those clay platelets had to disperse in PMMA. The ability of OMMT to
carry a certain load applied in PMMA matrix enhances the tensile strength in all composites.
TIBMP are compatible with PMMA matrix, and significantly improves the tensile
properties of PMMA composites.
Corrosion is a natural deterioration process that destructs metal surface. Metal of highly
protected by passivation layer such as Stainless Steel 316L also undergoes pitting corrosion
when continuously exposed to aggressive environment. To overcome this phenomenon, application
of epoxy based coating with addition of zinc oxide- poly (3,4-ethylenedioxythiophene)
doped with poly (styrene sulphonate) hybrid nanocomposite additive was introduced as
paint/metal surface coating. The compatibility between these two materials as additive
was studied by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD),
Field Emission Scanning Electron Microscopy/Energy-Dispersive X-ray spectroscopy (FESEM/EDX)
and Transmission Electron Microscopy (TEM) analysis. The effect of nanocomposite
wt.% in epoxy based coating with immersion duration in real environment on corrosion
protection performance was analyzed through potentiodynamic polarization analysis. The
main finding showed that addition of hybrid nanocomposite had increased corrosion protection
yet enhanced corrosion process when excess additives was loaded into epoxy coating.
Addition of 2 wt.% ZnO-PEDOT:PSS was found significantly provided optimum corrosion
protection to stainless steel 316L as the corrosion rate for 0 day, 15 days and 30 days of
immersion duration is 0.0022 mm/yr, 0.0004 mm/yr and 0.0015 mm/yr; respectively.
The present article evaluates the composition and synthesis of hydrogel beads. Hydrogels, owing to their known biocompatibility, are widely used in drug delivery as a host (or drug carrier). Hydrogels, owing to their physical, chemical and biological properties, are popular in many aspects. Hydrogels are crosslinked-hydrophilic polymers and commercialized/synthesized in both natural and synthetic forms. These polymers are compatible with human tissues, therefore can be potentially used for biomedical treatments. Hydrogels in drug delivery offer several points of interest such as sustainability, and sensitivity without any side-effects as compared to traditional methods in this field. Drugs can encapsulate and release continuously into the targets when hydrogels are activated/modified magnetically or by fluorescent materials. It is crucial to develop new crosslinked polymers in terms of "biocompatibility" and "biodegradability" for novel drug delivery platforms. In the event that the accomplishments of the past can be used into the longer terms, it is exceedingly likely that hydrogels with a wide cluster of alluring properties can be synthesized. The current review, offers an updated summary of latest developments in the nanomedicines field as well as nanobased drug delivery systems over broad study of the discovery/ application of nanomaterials in improving both the efficacy of drugs and targeted delivery of them. The challenges/opportunities of nanomedicine in drug delivery also discussed. SCOPE OF THE RESEARCH: Although several reviews have been published in the field of hydrogels, however many of them have just centralized on the general overviews in terms of "synthesis" and "properties". The utilization of hydrogels and hydrogel-based composites in vital applications have been achieved a great interest. In this review, our aim is to recap of the key points in the field of hydrogels such as; a) hydrogel nanocomposites, b) magnetic beads, c) biomedical applications, and d) drug delivery. In the same vein, these outlines will be expanded with emphasizing on the boon of magnetic beads and recent developments in this area.
New packaging materials are an emerging field in the food industry. Poor thermal, mechanical, chemical, and physical properties of biopolymers, and also their inherent permeability to gases and vapor have increased this interest. Biopolymeric materials (matrix) require fillers, which can react/interact with available matrix in order to provide new formulations with improved properties. Many studies have shown the potential use of metal nanoparticles in biopolymeric packaging and edible coatings for improving their properties. The current review summarizes the characterization of bio-nanocomposite films and edible coatings incorporated with metal nanoparticles on the shelf life and quality of tropical fruits, berries, climacteric/non-climacteric fruits and vegetables. It also provides a brief description of some advantages of bio-nanocomposite films and edible coatings applied to fruits and vegetables such as decreasing the color changes, respiration rate, weight loss and extended shelf life, delaying ripening and being environmentally friendly. The results of recent reports provide a better understanding of the impact of metal nanoparticles incorporated in biopolymers on the shelf life and the quality of fruits and vegetables.
In this work, the physicochemical and blood compatibility properties of prepared PU/Bio oil nanocomposites were investigated. Scanning electron microscope (SEM) studies revealed the reduction of mean fiber diameter (709 ± 211 nm) compared to the pristine PU (969 nm ± 217 nm). Fourier transform infrared spectroscopy (FTIR) analysis exposed the characteristic peaks of pristine PU. Composite peak intensities were decreased insinuating the interaction of the bio oilTM with the PU. Contact angle analysis portrayed the hydrophobic nature of the fabricated patch compared to pristine PU. Thermal gravimetric analysis (TGA) depicted the better thermal stability of the novel nanocomposite patch and its different thermal behavior in contrast with the pristine PU. Atomic force microscopy (AFM) analysis revealed the increase in the surface roughness of the composite patch. Activated partial thromboplastin time (APTT) and prothrombin time (PT) signified the novel nanocomposite patch ability in reducing the thrombogenicity and promoting the anticoagulant nature. Finally the hemolytic percentage of the fabricated composite was in the acceptable range revealing its safety and compatibility with the red blood cells. To reinstate, the fabricated patch renders promising physicochemical and blood compatible nature making it a new putative candidate for wound healing application.
Ayurveda oil contains numerous source of biological constituents which plays an important role in reducing the pain relief caused during bone fracture. The aim of the study is to fabricate the polyurethane (PU) scaffold for bone tissue engineering added with ayurveda amla oil using electrospinning technique. Scanning Electron Microscopy (SEM) analysis showed that the fabricated nanocomposites showed reduced fiber diameter (758 ± 185.46 nm) than the pristine PU (890 ± 116.91 nm). Fourier Infrared Analysis (FTIR) revealed the existence of amla oil in the PU matrix by hydrogen bond formation. The contact angle results revealed the decreased wettability (116° ± 1.528) of the prepared nanocomposites compared to the pure PU (100° ± 0.5774). The incorporation of amla oil into the PU matrix improved the surface roughness. Further, the coagulation assay indicated that the addition of amla oil into PU delayed the blood clotting times and exhibited less toxic to red blood cells. Hence, the fabricated nanocomposites showed enhanced physicochemical and better blood compatibility parameters which may serve as a potential candidate for bone tissue engineering.
Graphene/zinc oxide nanocomposite was synthesised via a facile, green and efficient approach consisted of novel liquid phase exfoliation and solvothermal growth for sensing application. Highly pristine graphene was synthesised through mild sonication treatment of graphite in a mixture of ethanol and water at an optimum ratio. The X-ray diffractometry (XRD) affirmed the hydrothermal growth of pure zinc oxide nanoparticles from zinc nitrate hexahydrate precursor. The as-prepared graphene/zinc oxide (G/ZnO) nanocomposite was characterised comprehensively to evaluate its morphology, crystallinity, composition and purity. All results clearly indicate that zinc oxide particles were homogenously distributed on graphene sheets, without any severe aggregation. The electrochemical performance of graphene/zinc oxide nanocomposite-modified screen-printed carbon electrode (SPCE) was evaluated using cyclic voltammetry (CV) and amperometry analysis. The resulting electrode exhibited excellent electrocatalytic activity towards the reduction of hydrogen peroxide (H2O2) in a linear range of 1-15 mM with a correlation coefficient of 0.9977. The sensitivity of the graphene/zinc oxide nanocomposite-modified hydrogen peroxide sensor was 3.2580 μAmM(-1) with a limit of detection of 7.4357 μM. An electrochemical DNA sensor platform was then fabricated for the detection of Avian Influenza H5 gene based on graphene/zinc oxide nanocomposite. The results obtained from amperometry study indicate that the graphene/zinc oxide nanocomposite-enhanced electrochemical DNA biosensor is significantly more sensitive (P
In the present study, a nanocomposite of f-MWCNTs-chitosan-Co was prepared by the immobilization of Co(II) on f-MWCNTs-chitosan by a self-assembly method and used for the quantitative determination of paracetamol (PR). The composite was characterized by field emission scanning electron microscopy (FESEM) and energy dispersive x-ray analysis (EDX). The electroactivity of cobalt immobilized on f-MWCNTs-chitosan was assessed during the electro-oxidation of paracetamol. The prepared GCE modified f-MWCNTs/CTS-Co showed strong electrocatalytic activity towards the oxidation of PR. The electrochemical performances were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Under favorable experimental conditions, differential pulse voltammetry showed a linear dynamic range between 0.1 and 400 μmol L-1 with a detection limit of 0.01 μmol L-1 for the PR solution. The fabricated sensor exhibited significant selectivity towards PR detection. The fabricated sensor was successfully applied for the determination of PR in commercial tablets and human serum sample.
Rapid detection of foodborne pathogens is crucial as ingestion of contaminated food products may endanger human health. Thus, the objective of this study was to develop a biosensor using reduced graphene oxide-carbon nanotubes (rGO-CNT) nanocomposite via the hydrothermal method for accurate and rapid label-free electrochemical detection of pathogenic bacteria such as Salmonella enterica. The rGO-CNT nanocomposite was characterized using Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction and transmission electron microscopy. The nanocomposite was dropped cast on the glassy carbon electrode and further modified with amino-modified DNA aptamer. The resultant ssDNA/rGO-CNT/GCE aptasensor was then used to detect bacteria by using differential pulse voltammetry (DPV) technique. Synergistic effects of aptasensor was evident through the combination of enhanced electrical properties and facile chemical functionality of both rGO and CNT for the stable interface. Under optimal experimental conditions, the aptasensor could detect S. Typhimurium in a wide linear dynamic range from 101 until 108 cfu mL-1 with a 101 cfu mL-1 of the limit of detection. This aptasensor also showed good sensitivity, selectivity and specificity for the detection of microorganisms. Furthermore, we have successfully applied the aptasensor for S. Typhimurium detection in real food samples.
Guanine (G), adenine (A), thymine (T), and cytosine (C) are the four basic constituents of DNA. Studies on DNA composition have focused especially on DNA damage and genotoxicity. However, the development of a rapid, simple, and multiplex method for the simultaneous measurement of the four DNA bases remains a challenge. In this study, we describe a graphite-based nanocomposite electrode (Au-rGO/MWCNT/graphite) that uses a simple electro-co-deposition approach. We successfully applied the developed sensor for multiplex detection of G, A, T, and C, using square-wave voltammetry. The sensor was tested using real animal and plant DNA samples in which the hydrolysis of T and C could be achieved with 8 mol L-1 of acid. The electrochemical sensor exhibited excellent sensitivity (G = 178.8 nA/μg mL-1, A = 92.9 nA/μg mL-1, T = 1.4 nA/μg mL-1, and C = 15.1 9 nA/μg mL-1), low limit of detection (G, A = 0.5 μg mL-1; T, C = 1.0 μg mL-1), and high selectivity in the presence of common interfering factors from biological matrixes. The reliability of the established method was assessed by method validation and comparison with the ultraperformance liquid chromatography technique, and a correlation of 103.7% was achieved.
Improving the stability of cuprous oxide (Cu2 O) is imperative to its practical applications in artificial photosynthesis. In this work, Cu2 O nanowires are encapsulated by metal-organic frameworks (MOFs) of Cu3 (BTC)2 (BTC=1,3,5-benzene tricarboxylate) using a surfactant-free method. Such MOFs not only suppress the water vapor-induced corrosion of Cu2 O but also facilitate charge separation and CO2 uptake, thus resulting in a nanocomposite representing 1.9 times improved activity and stability for selective photocatalytic CO2 reduction into CH4 under mild reaction conditions. Furthermore, direct transfer of photogenerated electrons from the conduction band of Cu2 O to the LUMO level of non-excited Cu3 (BTC)2 has been evidenced by time-resolved photoluminescence. This work proposes an effective strategy for CO2 conversion by a synergy of charge separation and CO2 adsorption, leading to the enhanced photocatalytic reaction when MOFs are integrated with metal oxide photocatalyst.
The widespread use of aesthetic fillings has highlighted their advantages and disadvantages. One
of the most troublesome features of earlier aesthetic materials was the difficulty of finishing the restoration surface to decrease adherence of food debris. The rougher the finished surface, the greater the possibility of bacterial accumulation and discolouration of restoration along the restoration margin with secondary caries formation. Aside from these clinical implications, patients are highly discerning and could detect roughness of 0.30 μm with their tongue. The aesthetic restoration should mimic the appearance of natural dentition and should have an enamel-like appearance. An increased demand for superior aesthetics from composite resin has increased the
demand for more eff icient and simple polishing techniques. The development of nanocomposites has given a new perspective to the polishing of composite resins. Nanocomposites claim the advantage of improved gloss, optical characteristics and reduced wear. To date, results of in vitro studies have been equivocal regarding the most efficient and effective polishing system. There is variation in the effects of different finishing and polishing instruments on the surface roughness due to great diversity in size, shape, composition and distribution of the filler particles of composite resins, type of resin and a wide variety of finishing and polishing instruments. This paper will
review the different factors that affect polishing techniques used in achieving the desired polish on
composite resin restorations.
The aim of the study was to determine the depth of cure of a new nanocomposite when exposed to different curing times and also when different shades were polymerized. The nanocomposite, Filtek Supreme (3M ESPE), was packed into 96 plastic cylindrical moulds measuring 4 mm in internal diameter and 8 mm in length and then polymerized using a conventional quartz-tungsten-halogen light curing unit. The first part of the study involved curing 16 samples each of A2 shade of the nanocomposite at exposure times of 20s, 40s, 60s and 120s. For the second part, a similar number of samples of the dentinal opacity shades of A2, B3 and A4 of the nanocomposite were polymerized at a constant exposure time of 40s. The depth of polymerization of the nanocomposite in each sample was measured using a digimatic indicator. Curing depths were found to increase significantly (P < 0.05) with longer exposure time (20s < 40s < 60s < 120s) and decrease significantly with darker shades (A2 > B3 > A4).