3-thiopheneacetic Acid Research Articles

A Review on Self-Assembly Driven Optoelectronic Properties of Polythiophene-Peptide and Polythiophene-Polymer Conjugates.

Polythiophene (PT) is an important conducting polymer for its outstanding optoelectronic properties. Here, we delineate the self-assembly-driven optoelectronic properties of PT-peptide and PT-polymer conjugates, taking examples from recent literature reports. PT-peptide conjugates made by both covalent and noncovalent approaches are discussed. Poly(3-thiophene acetic acid) (P3TAA) covalently coupled with Gly-Gly-His tripeptide, C-protected and deprotected tripeptide H2N-F-F-V-OMe, etc. exhibits self-assembly-driven absorbance, fluorescence, photocurrent, and electronic properties. Noncovalent PT-peptide conjugates produced via ionic, H-bonding, and π-stacking interactions show tunable morphology and optoelectronic properties by varying the composition of a component. PT conjugated with Alzheimer's disease peptide (KLVFFAE, Aβ16-22) shows enhanced photocatalytic water splitting, cationic PT(CPT-I)-perylene bisimide-appended dipeptide (PBI-DY), and anionic PT-perylene diimide-appended cationic peptide (PBI-NH3+) conjugates and exhibits self-assembly-driven enhanced photoswitching and organic mixed electronic and ionic conductivity (OMEIC) properties. In the PT-polymer conjugates, self-assembly-driven optoelectronic properties of covalently produced PT-random copolymers, PT-block copolymers, PT-graft-random copolymers, and PT-graft-block copolymer conjugates are discussed. The HOMO-LUMO levels of hyperbranched polymers are optimized to obtain better power conversion efficiency (PCE) in the bulk heterojunction (BHJ) solar cell than in linear polymers, and P3TAA-ran-P3HT (43 mol % P3TAA) conjugated with MAPbI3 perovskite exhibits higher PCE (10%) than that with only P3TAA hole-transporting material. In the ampholytic polythiophene (APT), on increasing pH, the morphology changes from the vesicle to fibrillar network for the dethreading of the PT chain, resulting in a red shift of the absorbance peak, an enormous increase in PL intensity, lowering of the charge transfer resistance, and an induction of Warburg impedance for the release of quencher I- ions. The PT-g-(PDMAEMA-co-PGLU-HEM) graft copolymer self-assembles with Con-A lectin, causing fluorescence quenching, and acts as a sensor for Con-A with a LOD of 57 mg/L. Varying sequences of the block copolymer containing pH-responsive PDMAEMA and temperature-responsive PDEGMEM grafted to the PT backbone shows different self-assembly, optical, electronic, and photocurrent properties depending on the proximity and preponderance of the block sequence on the PT backbone.

Novel antifungal compound from Prunella vulgaris: An in-silico approach towards the discovery of potent inhibitor to combat phytopathogenic fungi

Phytopathogenic fungi wreak havoc on crops, causing substantial losses globally. Numerous chemical fungicides are employed to manage the pathogen, yet effectiveness is limited and resistance concerns are rising. The current study aimed to identify the antifungal compound from the spikes of a significant medicinal herb Prunella vulgaris subsp. hispida (Benth.) Hultén as an alternative to combat the fungi. In vitro, antifungal assay revealed that the ethyl acetate extract of P. vulgaris emerged as a potent inhibitor against selected fungal phytopathogens Fusarium oxysporum, Alternaria solani and Penicillium digitatum. Through chromatographic analysis, 32 compounds were identified from the active fraction of ethyl acetate extract. Notably, five compounds were reported for the first time from P. vulgaris. They include dichloroacetic acid, tridec-2-ynyl ester (1), phenol, 3,5-bis(1,1-dimethylethyl)- (2), 2-thiopheneacetic acid, 3-tetradecyl ester (3), 1H-1,2,4-triazol-3-amine, 1-ethyl- (4) and sulfurous acid, octadecyl 2-propyl ester (5). Compound 1 was identified as the most abundant. NMR studies confirmed the presence of compound 1, prompting its selection for in silico antifungal analysis. Various computational models showcased that Compound 1 achieved a high bioactive score and met the criteria for medicinal chemistry friendliness. Additionally, a molecular docking study revealed that compound 1 displayed a good binding affinity with the multiple target fungal enzymes such as scytalone dehydratase and cytochrome P450 which is a prime target for antifungal drugs. Remarkably, this study marks the first detection of compound 1’s effectiveness against phytopathogenic fungi. Therefore, compound 1 holds the potential to pave the way for the development of a potent novel fungicide.

Intrinsic tenase blood biomarker imprinted polymer-aptasensor with carbon nanohorn and gold nano-urchin construct for primitive-phase diagnosis of haemophilia B

The selective biomimetic aptasensor for blood coagulation factor IX protein (FIX) detection was developed using an interdigitated electrode with an Archimedean spiral pattern. In contrast to conventional molecularly imprinted polymer (MIP) techniques, aptamer was employed as a macromonomer to accelerate double binding affinity. To preserve the aptamer profile in its protein-binding orientation, FIX protein and thiol-modified RNA aptamers were complexed prior to MIP fabrication. The immobilized aptamer-FIX complex was surrounded by a polymer generated by the electropolymerization of 3-thiophene acetic acid (3TAA). Subsequent to FIX protein removal, leaves imprinted cavities facilitate selective FIX protein detection in conjunction with the affinity of embedded aptamer affinity. The Archimedean IDE surface was functionalized with carbon nanohorn (CNH) and gold nanourchin (GNU) to increase the imprinting ratios and sensor sensitivity. The developed FIX-aptasensor shows a detection limit of 0.06 fM, which is 660-fold higher than aptamer-embedded MIP nanoparticles. Moreover, the sensor exhibited greater selectivity for FIX, discriminating IgG and thrombin. As a preliminary study for clinical use, the sensor was used to analyze human serum without target spiking and detected FIX-protein with a relative standard deviation of 9.18%. It was ascertained that the sensor maintained 85% sustained performance for a duration of five weeks.

Platinum decorated phosphorous doped graphitic carbon nitride supported molecularly imprinted carbon fibre electrode as a nano-interface for the detection of butylated hydroxy anisole

This research generated an electrochemical sensor using a carbon fibre (CFP) paper electrode coated using platinum-decorated phosphorous doped graphitic carbon nitride (Pt/PgCN). This sensor was designed to detect butylated hydroxy anisole (BHA) selectively and sensitively. The molecularly imprinted polymers (MIPs) were synthesized onto the Pt/PgCN coated CFP surface through electropolymerization using BHA as a template and 3-thiophene acetic acid as monomer. Numerous analytical methods were used to characterise the sensor electrode, including cyclic voltammetry, impedance spectroscopy, and electron microscopy. The results showed that the synergetic effect of PgCN, Pt nanoparticles, and PTAA, PgCN and Pt had a positive impact on the electrochemical detection, the sensor's linear range was determined to be between 5 × 10−10 M and 2.1 × 10−7 M. The sensor demonstrated excellent stability, good reproducibility, and high selectivity for detecting BHA. Moreover, the proposed sensor successfully detected BHA in real samples.

An electrochemiluminescence sensor based on CsPbBr3 -zquantum dots and poly (3-thiophene acetic acid) cross-linked nanogold imprinted layer for the determination of benzo(a)pyrene in edible oils.

A novel quench molecularly imprinted electrochemiluminescence sensor (MIECLS) based on a covalent organic framework composite (COF-300-Au) with enhanced electrochemiluminescence (ECL) signal from CsPbBr3 quantum dots and cross-linked 3-thiopheneacetic acid functionalized AuNPs (3-TAA@AuNPs) was developed for the detection of the environmental pollutant benzo(a)pyrene (BaP). A composite material constructed of COF-300-Au with a large specific surface area served as the sensor's support substrate, providing more CsPbBr3 and imprint recognition sites. Electropolymerization was then employed to form an AuNPs three-dimensional imprinting layer with polythiophene cross-linked using BaP as a template and 3-TAA@AuNPs as a functional monomer. A specific cross-linked imprinting recognition effect was recorded on BaP along with the quenching effect of quinones. The density functional theory (DFT) evaluation of the binding mechanism between 3-TAA@AuNPs and BaP revealed powerful MIECLS toward the detection of BaP at concentrations ranging from 10-14 to 10-5M, with a detection limit of as low as 4.1×10-15 M.

Ticarcillin degradation product thiophene acetic acid is a novel auxin analog that promotes organogenesis in tomato.

Efficient regeneration of transgenic plants from explants after transformation is one of the crucial steps in developing genetically modified plants with desirable traits. Identification of novel plant growth regulators and developmental regulators will assist to enhance organogenesis in culture. In this study, we observed enhanced shoot regeneration from tomato cotyledon explants in culture media containing timentin, an antibiotic frequently used to prevent Agrobacterium overgrowth after transformation. Comparative transcriptome analysis of explants grown in the presence and absence of timentin revealed several genes previously reported to play important roles in plant growth and development, including Auxin Response Factors (ARFs), GRF Interacting Factors (GIFs), Flowering Locus T (SP5G), Small auxin up-regulated RNAs (SAUR) etc. Some of the differentially expressed genes were validated by quantitative real-time PCR. We showed that ticarcillin, the main component of timentin, degrades into thiophene acetic acid (TAA) over time. TAA was detected in plant tissue grown in media containing timentin. Our results showed that TAA is indeed a plant growth regulator that promotes root organogenesis from tomato cotyledons in a manner similar to the well-known auxins, indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). In combination with the cytokinin 6-benzylaminopurine (BAP), TAA was shown to promote shoot organogenesis from tomato cotyledon in a concentration-dependent manner. To the best of our knowledge, the present study reports for the first time demonstrating the function of TAA as a growth regulator in a plant species. Our work will pave the way for future studies involving different combinations of TAA with other plant hormones which may play an important role in in vitro organogenesis of recalcitrant species. Moreover, the differentially expressed genes and long noncoding RNAs identified in our transcriptome studies may serve as contender genes for studying molecular mechanisms of shoot organogenesis.

Intermolecular interactions enabled a semiconducting 2D supermolecular complex with robust humidity sensing performance

As essential multifunctional materials, metal-organic complexes are attractive candidates showing superior sensing performance. However, the development of complex-based electronic sensors is still greatly limited by the low conductivity and unsatisfactory properties. Here, we report a new complex with formula of [Cd2(TAA)4(2,2′-bpy)2] (denoted as CdL, HTAA = 3-thiopheneacetic acid, 2,2′-bpy = 2,2′-bipyridine) synthesized via room-temperature precipitation. Hirshfeld surface analysis reveals the important effects of hydrogen bonds (54.6%) and Van der Waals interaction (31.5%) for constructing its 2D supermolecular structure. Favored by these intermolecular interactions, the semiconducting CdL exhibits high electronic conductivity at room temperature (1.71 × 10−5 S/cm). Consequently, the CdL powder was fabricated into a planar impedimetric device with high performance. Particularly, the CdL sensor exhibited high sensitivity (1.2 × 103), fast response (6 s), and small hysteresis (0.92%) in total relative humidity range of 33%−97%. In addition, complex impedance analysis was adopted to clarify the sensing mechanism of CdL. This contribution demonstrates the possible application of low-dimensional complexes in humidity sensors.

ZnO and Au nanoparticles supported highly sensitive and selective electrochemical sensor based on molecularly imprinted polymer for sulfaguanidine and sulfamerazine detection

This study aimed to develop a molecularly imprinted polymer (MIP) sensor using electropolymerization of thiophene acetic acid monomer around template molecules, sulfaguanidine (SGN) and sulfamerazine (SMR), for selective and sensitive detection of both antibiotics. Au nanoparticles were then deposited on the modified electrode surface, and SGN and SMR were extracted from the resulting layer. Surface characterization, changes in the oxidation peak current of both analytes, and investigation of the electrochemical properties of the MIP sensor were examined using scanning electron microscopy, cyclic voltammetry, and differential pulse voltammetry. The developed MIP sensor with Au nanoparticles showed a detection limit of 0.030 µmol L−1 and 0.046 µmol L−1 for SGN and SMR, respectively, with excellent selectivity in the presence of interferents. The sensor was successfully used for SGN and SMR analysis in human fluids, including blood serum and urine, with excellent stability and reproducibility.

Engineered synthetic nanobody-based biosensors for electrochemical detection of epidermal growth factor receptor

Two engineered synthetic nanobody-based nanobiocomposite platforms were developed for label-free electrochemical detection of the epithelial growth factor receptor (EGFR) biomarker. Screen-printed carbon electrodes (SPCE) were decorated either with NiO nanoparticles (NPs) or poly(thiophene acetic acid) (PTAA) to link the anti-EGFR nanobody (Nb) and form nanobiocomposites for detecting the EGFR biomarker by electrochemical impedance spectroscopy (EIS). The nanoarchitectures were prepared by in situ electrosynthesis of NiO NPs or PTAA layers at SPCEs. A modified version of the 9G8 Nb (Nb9G8m), specific for the EGFR (anti-EGFR), was designed and produced as the nanobiosensor bioreceptor. This Nb was engineered to provide a hexahistidine tag (6xHis-tag) and a lysine (Lys) dual functionality to form a (6xHis-tag)/Ni2+ or Lys/PTAA interface. The biosensing interfaces were characterized by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammetry, and EIS. The nanobody/nanobiocomposite-based biosensors detected EGFR proteins in a linear range from 0.25 to 50 μg mL−1 and 0.5 to 50 μg mL−1, with limits of detection of 0.46 μg mL−1 and 1.14 μg mL−1, for NiO- and PTAA-based platforms, respectively. The biosensing platforms offer high simplicity, specificity, and selectivity to detect EGFR, but Nbs can be readily engineered to detect other (glycol)proteins. Finally, as a proof of concept, the EGFR was detected in several tumor cell lines, differentiating biomarker expression among them.

Nanostructured poly(thiophene acetic acid)/Au/poly(methylene blue) interface for electrochemical immunosensing of p53 protein.

A poly(thiophene acetic acid)/Au/poly(methylene blue) nanostructured interface was electrochemically assembled step-by-step on screen-printed carbon electrodes (SPCE) for label-free detection of p53 protein. The initial electrical conductive properties of the polymeric interface were increased with an additional layer of poly(methylene blue) electropolymerized in the presence of gold nanoparticles. The nano-immunosensing architecture was prepared by covalent immobilization of anti-p53 antibodies as bioreceptors through the poly(thiophene acetic acid) moieties. The nano-immunosensor assembly was extensively characterized by ultraviolet-visible spectrophotometry, dynamic and electrophoretic light scattering, scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, atomic force microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Under optimal conditions, p53 was specifically and selectively detected by square wave voltammetry in a linear range between 1 and 100ngmL-1 with a limit ofdetection of 0.65ngmL-1. In addition, the electrochemical nano-immunosensor detected p53 in spiked human serum samples and colorectal cancer cell lysates, and the results were validated with a standard spectrophotometric method using a paired samples t test, which did not exhibit significant differences between both methods. The resultant p53 nano-immunosensor is simple to assemble, robust, and has the potential for point-of-care biomarker detection applications.

Tau seeds from patients induce progressive supranuclear palsy pathology and symptoms in primates.

Progressive supranuclear palsy is a primary tauopathy affecting both neurons and glia and is responsible for both motor and cognitive symptoms. Recently, it has been suggested that progressive supranuclear palsy tauopathy may spread in the brain from cell to cell in a 'prion-like' manner. However, direct experimental evidence of this phenomenon, and its consequences on brain functions, is still lacking in primates. In this study, we first derived sarkosyl-insoluble tau fractions from post-mortem brains of patients with progressive supranuclear palsy. We also isolated the same fraction from age-matched control brains. Compared to control extracts, the in vitro characterization of progressive supranuclear palsy-tau fractions demonstrated a high seeding activity in P301S-tau expressing cells, displaying after incubation abnormally phosphorylated (AT8- and AT100-positivity), misfolded, filamentous (pentameric formyl thiophene acetic acid positive) and sarkosyl-insoluble tau. We bilaterally injected two male rhesus macaques in the supranigral area with this fraction of progressive supranuclear palsy-tau proteopathic seeds, and two other macaques with the control fraction. The quantitative analysis of kinematic features revealed that progressive supranuclear palsy-tau injected macaques exhibited symptoms suggestive of parkinsonism as early as 6 months after injection, remaining present until euthanasia at 18 months. An object retrieval task showed the progressive appearance of a significant dysexecutive syndrome in progressive supranuclear palsy-tau injected macaques compared to controls. We found AT8-positive staining and 4R-tau inclusions only in progressive supranuclear palsy-tau injected macaques. Characteristic pathological hallmarks of progressive supranuclear palsy, including globose and neurofibrillary tangles, tufted astrocytes and coiled bodies, were found close to the injection sites but also in connected brain regions that are known to be affected in progressive supranuclear palsy (striatum, pallidum, thalamus). Interestingly, while glial AT8-positive lesions were the most frequent near the injection site, we found mainly neuronal inclusions in the remote brain area, consistent with a neuronal transsynaptic spreading of the disease. Our results demonstrate that progressive supranuclear palsy patient-derived tau aggregates can induce motor and behavioural impairments in non-human primates related to the prion-like seeding and spreading of typical pathological progressive supranuclear palsy lesions. This pilot study paves the way for supporting progressive supranuclear palsy-tau injected macaque as a relevant animal model to accelerate drug development targeting this rare and fatal neurodegenerative disease.

Determination of acrylamide by a quartz crystal microbalance sensor based on nitrogen-doped ordered mesoporous carbon composite and molecularly imprinted poly (3-thiophene acetic acid) with gold nanoparticles

In this study, a quartz crystal microbalance (QCM) sensor based on nitrogen-doped ordered mesoporous carbon modified-AuNPs (NOMC-Au) modified layer and cross-linked 3-thiopheneacetic acid functionalized AuNPs ([email protected]) imprinted layer was developed for the detection of acrylamide as a hazardous substance in thermal processing. The composite modification layer formed by NOMC-Au was used as support material for QCM gold chips (AuE), and [email protected] were then introduced to the highly selective imprinting modification layer by electropolymerization using propionamide as a template. The use of [email protected] based molecularly imprinted polymer (MIP) on QCM was also evaluated and optimized, and the data were compared with non-imprinted polymer (NIP) and MIP/AuE chip layers. Results showed that a highly crosslinked three-dimensional reticular imprinted layer improved the acrylamide signals in the range of 0.08 ng/mL −100.0 ng/mL, and the sensor was suitable for food samples analysis at concentrations as low as 5.1 pg/mL. The proposed QCM sensor is very useful for future selective and sensitive detection of acrylamide in food samples.

Surface tempering of poly-(3 thiophene acetic acid) coated carbon fiber paper electrode with spine-like cobalt inorganic phosphate: An efficacious electrochemical metol sensor

N-methyl-p-aminophenol sulfate (metol) is a photographic developing agent that has a toxic effect on humans and aquatic life. A cost-effective and sensitive electrochemical sensor was developed by electrodepositing Co-Pi over poly-(3 thiophene acetic acid) coated carbon fiber paper electrode (Co-Pi/PTAA/CFP) for the determination of metol (ML). Surface modification of Co-Pi facilitates superior electrocatalytic performance by offering more active sites and faster electron transport kinetics. The Physico-chemical characterization of the fabricated electrode was carried out by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDS), Optical profilometer, Fourier transform infrared spectroscopy (FTIR), and electroanalytical techniques. The electrochemical studies were performed using Cyclic voltammetry (CV), Electron Impedance spectroscopy (EIS), and Differential pulse voltammetric (DPV). DPV studies revealed excellent sensing performance for ML, with a wide linear dynamic range of 6 nM to 800 nM, and a limit of detection (LOD) of 2 nM. A distinctive oxidative anodic peak was observed at 0.11 V indicating the excellent electrochemical performance of the electrode. The results suggested that the developed electrode exhibited good catalytic activity, selectivity, and sensitivity towards the electrochemical determination of ML. Further, the developed electrode was extended to its application in real samples obtained from lake water and domestic wastewater.

The Influence of Heparan Sulfate on Breast Amyloidosis and the Toxicity of the Pre-fibrils Formed by β-casein.

Heparan sulfate (HS) as a mediator is usually involved in both inflammation and fibrosis. Besides, pre-fibrils are the intermediates of amyloid fibrils that usually cause cell death and tissue damage, like the amyloid-β in Alzheimer's disease, α-synuclein in Parkinson disease and islet amyloid polypeptide in type II diabetes mellitus. However, the related study was involved rarely in breast. Therefore, the combing technologies including hematoxylin-eosin staining and thioflavin S staining were used to investigate the influence of HS on breast amyloidosis. To further study the toxicity of the pre-fibrils formed by β-casein on the HC11 cells and the breast mammary gland, the combing technologies including pentamer formyl thiophene acetic acid fluorescence analysis, MTT assay, Annexin V/PI staining and hematoxylin-eosin staining were performed. The results demonstrated that HS, acted as an endogenous molecule, induced the inflammation and amyloid fibril formation at the same time, and there was a close relationship between inflammation and fibrosis of breast. In addition, the pre-fibrils formed by β-casein were toxic because they induced the death and apoptosis of HC11 cells, as well as the inflammation of mammary gland of rats. Therefore, the early examination and identify of the pre-fibrils in the breast were worth considering to prevent the disease development, and it was interesting to explore the HS mimetics to impair the breast amyloidosis and attenuate the inflammatory response in the future.

Design of imprinting matrix for dual template sensing via electropolymerized polythiophene films.

This work presents the design of 3-thiophene acetic acid (3-TAA) polymer matrix based molecularly imprinted polymer (MIP)/reduced graphene oxide (RGO) composite for sensitive and selective detection of antipyrine (AnP) and ethionamide (ETH) simultaneously. Dual drug embedded molecularly imprinted polymer (MIP) based electrochemical sensor was developed via electropolymerization of 3-TAA. AnP and ETH were embedded inside a polymer matrix based on their 3-D orientation and interaction(s) with functional monomer(s). Their extraction from polymeric matrix generates cavities complimentary to shape and size of AnP and ETH. The extraction of templates was confirmed by differential pulse voltammetry (DPV) as well as high-performance liquid chromatography (HPLC). The designed sensor selectively captures and produces the electrochemical signal for imprinted drugs. The electrochemical behaviour of AnP and ETH was investigated by DPV technique. The sensitivity for both drug molecules was commendable on a single polymeric composite with RGO on GC electrode (LOD of 0.117 μM for AnP and 0.15 μM for ETH). Also, the sensor exhibited excellent selectivity towards AnP and ETH in the presence of other analogous interferent molecules. Thus, the designed sensor showed high sensitivity as well as high selectivity for imprinted dual drug molecules on a single platform.

Improving the stability and efficiency of inorganic CsPbI2Br perovskite via surface reconstruction strategy

Inorganic CsPbX3 (X = Cl, Br, I) perovskite without volatile organic components in crystal lattice, has outstanding thermal stability and broad application prospects. Various strategies have been adopted to restrain the notorious phase transition process (from cubic to orthorhombic phase) for high photoelectric conversion efficiency (PCE). Nevertheless, most studies simply focus on the surface passivation of perovskite films, ignoring the influence of surface element segregation, which is inevitable during perovskite crystallization and growth process. Herein, 2-thiopheneacetic acid (2-TPAA) was adopted to reconstruct the surface of CsPbI2Br film via secondary growth process. The constituent elements of CsPbI2Br especially Br- enrich on the surface under the action of 2-TPAA. Meanwhile, the carboxyl and thiophene groups of 2-TPAA bidentate anchor Pb2+ ions respectively, forming protective layer to inhibit the invasion of external factors. In addition, the film morphology, moisture resistance, thermodynamic stability as well as carrier transport performance of perovskite films also get improved significantly. The black phase of CsPbI2Br survives in air ambient for several days, via the synergism of surface reconstruction and passivation effect. Furthermore, the device PCE increased to 15.03%, and retained 90% initial PCE during 400 d aging. The surface reconstruction strategy provides a convenient method to improve the phase stability of CsPbI2Br perovskite films in air ambient.

Gadolinium and Polythiophene Functionalized Polyurea Polymer Dots as Fluoro-Magnetic Nanoprobes.

A rapid and one-pot synthesis of poly 3-thiopheneacetic acid (PTAA) functionalized polyurea polymer dots (Pdots) using polyethyleneimine and isophorone diisocyanate is reported. The one-pot mini-emulsion polymerization technique yielded Pdots with an average diameter of ~20 nm. The size, shape, and concentration of the surface functional groups could be controlled by altering the synthesis parameters such as ultrasonication time, concentration of the surfactant, and crosslinking agent, and the types of isocyanates utilized for the synthesis. Colloidal properties of Pdots were characterized using dynamic light scattering and zeta potential measurements. The spherical geometry of Pdots was confirmed by scanning electron microscopy. The Pdots were post-functionalized by 1,4,7,10 tetraazacyclododecane-1,4,7,10-tetraacetic acid for chelating gadolinium nanoparticles (Gd3+) that provide magnetic properties to the Pdots. Thus, the synthesized Pdots possess fluorescent and magnetic properties, imparted by PTAA and Gd3+, respectively. Fluorescence spectroscopy and microscopy revealed that the synthesized dual-functional Gd3+-Pdots exhibited detectable fluorescent signals even at lower concentrations. Magnetic levitation experiments indicated that the Gd3+-Pdots could be easily manipulated via an external magnetic field. These findings illustrate that the dua- functional Gd3+-Pdots could be potentially utilized as fluorescent reporters that can be magnetically manipulated for bioimaging applications.

Determination of Active Phytochemical Compounds of Alhagi Maurorum using Gas Chromatography-Mass Spectroscopy (GC-MS)

Alhagi maurorum (camel thorn) is a grayish, evergreen, deeply rooting plant that has spiny needle -like branches. In our study, the phytochemical contents of the root ethanoloic extract of A. maurorum were determined by using gas chromatography-mass spectroscopy (GC-MS). Thirty two chemical constituents were identified. We revealed the existence of oxalic acid, anti-2 acetoxyacetaldoxime, sulfone, butyl isopropyl, 2,3-pentanedione, 2-butanone, n,n,o triacetylhydroxylamine. di(1,2,5-oxadiazole)[3,4-b;3,4-e]pyrazine, isobutane,3,4-hexanedione,3-hexanone, pentane, 3-pentanone, 3-butene, 2-thiopheneacetic acid, 2-pyrazoline, 4-hepten-3-onemethylphosphonic acid, butane, propanoic acid, methane, azetidine, heptane, butanoic acid, 4-heptanone, 3,5-dimethyl-4-octane, 3-methoxy-1-pentene, oxirane, 2-undecen-4-ol, 1-heptane, 3- methoxy, acrolein, dimethylacetal, hydrogen azide, ethylenimine, acetic acid, and decane. The results showed that the roots of A. marrourum have active compounds that are known to have anti-inflammatory, anti-cancer, antibacterial, anti-ulcerogenic, anti-fungal, anticancer, and anti-malarial activities.

Electro fabrication of molecularly imprinted sensor based on Pd nanoparticles decorated poly-(3 thiophene acetic acid) for progesterone detection

In recent years, scientific community has witnessed substantial interest in the design and engineering of electrodes as sensing platforms towards sensitive and selective detection of hormones. An electrochemical strategy for the detection of progesterone was proposed by generating a composite film comprising of palladium nanoparticles with 3-thiophene acetic acid (3-TAA) coupled with molecular imprinting technology. Progesterone molecule was employed as the template while generating molecular imprints by electropolymerization on the surface of the Carbon Fibre Paper (CFP) electrode. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry were used to analyse the various modified working electrodes (CV). Characterization methods included field emission scanning microscopy, energy dispersive X-ray spectrometry, optical profilometry, and X-ray photon electron spectroscopy. Pd nanoparticles resulted in enhanced sensitivity and molecular imprinting technology contributed to its specificity. Because of the molecular cavities created on the removal of the template molecule, Nyquist plots data showed that the MIP/Pd/CFP electrode had the lowest charge transfer resistance compared to other control electrodes.

Detection of chlorpyrifos based on molecular imprinting with a conducting polythiophene copolymer loaded on multi-walled carbon nanotubes

Molecular imprinting technique (MIT) with electrochemical sensing provides an attractive tool for the fabrication of sensors. Incorporation of conducting copolymer and surface imprinting strategies in the sensing device improves the conducting properties and poor template accessibility, slow binding kinetics at the same time. Here, this technique was employed with conducting polymers with multi-walled carbon nanotubes (MWCNT) to build an electrochemical sensor for detecting Chlorpyrifos (CPF) in vegetable sample solutions. In this work, we aimed at synthesizing a copolymer of 3-thiophene acetic acid and 3,4-ethylene dioxythiophene on the surface of MWCNT. We further constructed a polymer drop-casted glassy carbon electrode sensor for ultrasensitive detection CPF. Under optimal conditions, the sensor exhibited a very low limit of detection (LOD) of 4.0 × 10-12 M for CPF. Due to the excellent repeatability and reusability of the materials, this study and findings have potential applications in the monitoring of pesticides from vegetable samples.