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Shape specific nanoparticles are getting a tremendous research interests due to their change in property with the shape. As far our knowledge, the impact of change in the shape of nanoparticle used as platform during synthesis of molecularly imprinted polymers (MIPs) has not been reported or tried. Herein, we have studied the effect of shape of silver nanoparticles (AgNPs) on the performance of MIPs. For this, different shaped (spherical, hexagon and cube) AgNPs were prepared by green-synthesis approach, modified with vinyl group, embedded into the shell of magnetic carbon nanoparticles and used as one of the functional monomer during tramadol imprinted polymer synthesis. The resulting MIP@Ag/C@Fe 3 O 4 was used for adsorption, removal and detection of tramadol, which is gaining importance due to their recent ban in several countries. The change in behaviour of resulting MIPs, with the change in shape of the incorporated nanoparticles was studied in terms of electrocatalytic activity, surface area, adsorption capacity, and removal efficiency. Among their different shaped colleagues cube shaped AgNPs win the MIP race and exhibited the best performance owing to the presence of more facets in comparison to the others. Furthermore, the cube shaped AgNPs based MIP (MIP@Cube-Ag/C@Fe 3 O 4 ) was successfully applied for the detection of tramadol in human sera and pharmaceutical samples without any cross-reactivity. In addition to the advantages of low cost, high selectivity, sensitivity, good adsorption and removal properties, the resulting MIP format is biodegradable too i.e. the material will not create any environmental hazards after their use and could be very easily disposed off from the medium. [ABSTRACT FROM AUTHOR]

The present work reports an eco-friendly and economic method for the preparation of different shaped (spherical, rod, and sea-urchin) heteroatom-doped fluorescent carbon nanoparticles (CNPs) by a unique combination of sonochemical, microwave and hydrothermal approach. Not only in terms of chemical, herein, we used the green precursors i.e. six members from solonaceae family for the synthesis of CNPs. Among the various shapes of CNPs, the sea-urchin shape CNPs (SU-CNPs) shows the high product and quantum yield with good photostability, excellent water dispersibility, narrow size distribution and high storage ability. The high quantum yield of derived CNPs made them suitable for patterning and staining (fluorescent inks) as a better, economic and eco-friendly replacement of dyes. In addition, the synthesized SU-CNPs were employed for quantitative detection of a widely used nanomaterial i.e. zinc oxide nanoparticles (ZnO). The fluorescence sensor was successfully applied for the detection of ZnO nanoparticles in wastewater, human sera and some cosmetic samples without any cross-reactivity. Herein, for the first time, we have successfully used the SU-CNPs for live cell detection of ZnO nanoparticles. The in vitro cytocompatibility study demonstrated that the SU-CNPs were not harmful to the cell up to a very high concentration of 1500.0 mg L −1 and could be used for cell imaging. In addition, the SU-CNPs were successfully utilized for the qualitative and quantitative, intracellular detection of ZnO nanoparticle in breast cancer cell line i.e. MCF-7. [ABSTRACT FROM AUTHOR]

Dimension has a different and impactful significance in the field of innovation, research and technologies. Starting from one-dimension, now, we all are moving towards 3-D visuals and try to do the things in this dimension. However, we still have some very innovative and widely applicable nanomaterials, which have tremendous potential in the form of 2-D only i.e. graphene. In this review, we have tried to incorporate the reported pathways used so far for modification of 2-D graphene sheets to make is three-dimensional. The modified graphene been applied in many fields like supercapacitors, sensors, catalysis, energy storage devices and many more. In addition, we have also incorporated the conversion of 2-D graphene to their various other dimensions like zero-, one- or three-dimensional nanostructures. [ABSTRACT FROM AUTHOR]

The present work describes the preparation of a nanohybrid by a combination of the 2D graphene sheet and 0D graphene quantum dots (GQDs). The GQDs were prepared from natural green precursors i.e. carrot juice by the one-step hydrothermal process. To get the maximum fluorescence property from nanohybrid, the graphene sheets were chemically doped with cadmium sulphide (CdS). The as prepared nanohybrid was characterized by means of X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), fluorescence and UV–vis spectroscopic techniques. The nanohybrid was further modified to design a nano-iniferter, which shows dual property i.e. works as polymerization initiator as well as provides platform for synthesis of the nimesulide-imprinted polymer. For designing of imprinted polymer two biocompatible monomers (cystine monomer and N-vinyl caprolactam) were used, which provides biodegradability to the polymer matrix. The imprinted polymer shows a very good selectivity towards the detection of nimesulide with a limit of detection as low as 6.65 ng L −1 ( S / N =3). The sensor was also applied for the detection of nimesulide in real samples like human blood serum, plasma and urine samples as well as some pharmaceutical tablets. [ABSTRACT FROM AUTHOR]

Recently, the nanostructured modified molecularly imprinting polymer has created a great attention in research field due to its excellent properties such as high surface to volume ratio, low cost, and easy preparation/handling. Among the nanostructured materials, the carbonaceous material such as ‘graphene’ has attracted the tremendous attention of researchers owing to their fascinating electrical, thermal and physical properties. In this review article, we have tried to explore as well as compile the role of graphene-based nanomaterials in the fabrication of imprinted polymers. In other words, herein the recent efforts made to introduce selectivity in graphene-based nanomaterials were tried collected together. The major concern of this review article is focused on the sensing devices fabricated via a combination of graphene, graphene@nanoparticles, graphene@carbon nanotubes and molecularly imprinted polymers. Additionally, the combination of graphene and quantum dots was also included to explore the fluorescence properties of zero-band-gap graphene. [ABSTRACT FROM AUTHOR]

A very cost-effective, fast, sensitive and specific imprinted polymer modified electrochemical sensor for the targeted detection, removal and destruction of Escherichia coli bacteria was developed onto the surface of Ag–ZnO bimetallic nanoparticle and graphene oxide nanocomposite. The nanocomposite played a dual role in this work, as a platform for imprinting of bacteria as well as a participated in their laser-light induced photo killing. In terms of sensing, our proposed sensor can detect E. Coli as few as 10 CFU mL −1 and capture 98% of bacterial cells from their very high concentrated solution (10 5 CFU mL −1 ). Similarly to the quantitative detection, we have also investigated the quantitative destruction of E. Coli and found that 16.0 cm 2 area of polymer modified glass plate is sufficient enough to kill 10 5 CFU mL −1 in the small time span of 5 minutes. The obtained results suggest that our proposed sensor have potential to serve as a promising candidate for specific and quantitative detection, removal as well as the destruction of a variety of bacterial pathogens. [ABSTRACT FROM AUTHOR]

Like the two sides of a coin, any new invention or discovery also possess their two faces. Similarly, while nanomaterials were identified as a boon in several fields like industrial, medicinal or agriculture; some of them have been also validated as a risk to the environment and living organisms. In this report, we addressed an efficient optical method for the detection of popularly used titanium dioxide nanoparticle (TiO 2 ) by a size-specific imprinted polymer embedded heteroatom-doped carbon nanodots (CNDs) decorated at the surface of the water-soluble magnetic nanoparticle. The CNDs were prepared by an economic and eco-friendly one-step hydrothermal method using a series of Brassicaceae family members (i.e. radish, cabbage, broccoli, and cauliflower). The as prepared CNDs shows very good production (12.8%) and quantum yields (40.7%). The size-specific imprinted polymer is biocompatible and biodegradable in nature and was able to detect the TiO 2 nanoparticles with a high selectivity i.e. limit of detection (LOD)=6.88 ng L −1 (S/N=3) and remove the nanoparticle very efficiently. Furthermore, the method was successfully applied for the detection of TiO 2 nanoparticles in wastewater, human sera, and cosmetic samples. [ABSTRACT FROM AUTHOR]

In this work, we have reported a new approach on the use of stimuli-responsive molecularly imprinted polymer (MIP) for trace level sensing of alpha-fetoprotein (AFP), which is a well know cancer biomarker. The stimuli-responsive MIP is composed of three components, a thermo-responsive monomer, a pH responsive component (tyrosine derivative) and a highly fluorescent vinyl silane modified carbon dot. The synthesized AFP-imprinted polymer possesses excellent selectivity towards their template molecule and dual-stimuli responsive behavior. Along with this, the imprinted polymer was also explored as ‘OR’ logic gate with two stimuli (pH and temperature) as inputs. However, the non-imprinted polymers did not have such ‘OR’ gate property, which confirms the role of template binding. The imprinted polymer was also used for estimation of AFP in the concentration range of 3.96–80.0 ng mL −1 , with limit of detection (LOD) 0.42 ng mL −1 . The role of proposed sensor was successfully exploited for analysis of AFP in real human blood plasma, serum and urine sample. [ABSTRACT FROM AUTHOR]

The present work describes the fabrication of a selective and sensitive molecularly imprinted polymer (MIP)-based electrochemical sensor using a combination of surface imprinting and nanotechnology. The fabricated sensor was used for the detection of two major components of vitamin B 6 i.e. pyridoxine (Py) and pyridoxal-5′-phosphate (PLP) using the same MIP format. Herein, acrylic acid modified zero valent iron nanoparticles were combined with the copper nanoparticle, resulting in vinyl groups modified bimetallic Fe/Cu magnetic nanoparticles (BMNPs). These BMNPs have high surface to volume ratios, higher electro-catalytic activity, and are therefore, a suitable platform to synthesize specific MIP cavities for Py and PLP. Herein, two different MIP formats (for Py and PLP) were synthesized on the surface of vinyl silane modified pencil graphite electrodes by activator regenerated by an electron transfer-atom transfer radical polymerization (ARGET-ATRP) method. The sensor shows a good analytical performance for the detection of Py and PLP by a square wave stripping voltammetric technique (SWSV). The limit of detection (LOD) was calculated to be 0.040 µg L − 1 and 0.043 µg L − 1 for Py and PLP, respectively, at signal to noise ratio of 3. The sensors are highly selective for the templates and can detect them from multivitamin tablets, corn flakes, energy drinks, cerebrospinal fluid (CSF) and blood samples (serum, plasma and whole blood) without any interfering effect, suggesting the clinical applicability of the fabricated sensor. The sensor can also be used as better alternative to the commercially available ELISA kits which are rather complex, less sensitive and difficult to handle. [ABSTRACT FROM AUTHOR]

In this paper, for the first time, we have reported the novel synthesis of reduced graphene oxide (r-GO) dendrite kind of nanomaterial. The proposed r-GO dendrite possesses multifunctional properties in various fields of sensing and separation. The dendrite was synthesized by chemical reaction in different steps. Initially, the r-GO sheet was conjugated with silane group modified magnetic nanoparticle, resulting in nanoparticle decorated r-GO. The above r-GO sheet was further reacted with a new r-GO sheet, resulting in the formation of r-GO dendrite type of structure. Multifunctional behavior of this r-GO dendrite structure was studied by different methods. First, magnetic properties were studied by vibrating sample magnetometer (VSM) and it was found that dendrite structure shows good magnetic susceptibility (180.2 emu/g). The proposed r-GO dendrite also shows a very good antibacterial behavior for Escherichia coli and excellent electrochemical behavior towards ferrocyanide probe molecule. Along with these, it also acts as a substrate for the synthesis of molecularly imprinted polymer for europium metal ion, a lanthanide. The proposed imprinted sensor shows a very high selectivity and sensitivity for europium metal ion (limit of detection= 0.019 μg L −1 ) in aqueous as well as real samples. [ABSTRACT FROM AUTHOR]

In this work, a sensitive and selective electrochemical sensor for detection of prostate specific antigen (PSA) was developed using surface imprinting and nanotechnology. The multiwalled carbon nanotubes (MWCNTs) decorated with manganese nanoparticles was functionalized with thio-group to make a nano-iniferter. This nano-iniferter was used as a platform to synthesize a three-dimensional molecularly imprinted polymer matrix for PSA by controlled radical polymerization technique. The PSA-sensor displayed good analytical performance for the detection of PSA by square wave and differential pulse stripping voltammetric techniques. The limit of detection was calculated as low as 0.25 pg L −1 (from SWSV) and 3.04 pg L −1 (from DPSV) at signal to noise ratio of 3. The proposed sensor was successfully applied for the determination of PSA in human blood serum, urine, and forensic samples without any cross-reactivity. Thus this sensor offers high selectivity, sensitivity, simplicity and clinical applicability for PSA determination in sera of both the men and women, which have not been reported together in the previously reported systems. The sensor may be used as a better alternative for the commercially available ELISA kits for PSA determination. [ABSTRACT FROM AUTHOR]

In this work, we present a new approach to prepare the Ag@CdS core–shell fluorescent nanoparticles wrapped with molecularly imprinted polymer for ferritin macromolecule by capping with vinyl derivative of cysteine. The imprinted Ag@CdS nanoparticle was prepared via activator regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP) method onto the surface of vinyl silane modified pencil graphite electrode. Combination of Ag and CdS in a single motif causes the dual behavior of core shell nanoparticle, which shows enhanced fluorescence as well as electrochemical properties. The performance of the obtained imprinted sensor was investigated by cyclic voltammetry, electrochemical impedance spectroscopy, chronocoulometry, differential pulse voltammetry and fluorescence spectrophotometry. Under the optimal experimental conditions, the current response of the electrochemical sensor was linear to ferritin concentrations in the range from 1.99 to 23.43 µg L −1 , with the detection limit of 0.65 µg L −1 . Similarly, a linear response was obtained between fluorescence quenching of imprinted Ag@CdS and concentration of ferritin in the range from 4.0 to 91.0 µg L −1 , with limit of detection (LOD) of 1.3 µg L −1 . The method was successfully applied to the analysis of blood serum samples of five different men and women with acceptable recoveries of 99.7% and 100.3% (RSD in %=1.0–2.0). [ABSTRACT FROM AUTHOR]