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Molecularly imprinted fluorescent carbon dots (MI-FCDs) find numerous applications in analytical chemistry due to their outstanding photoluminescent properties and having specific pockets for the recognition of target molecules. Despite significant advances, practical applications of MI-FCDs-based fluorescent sensors are still in their initial stages. Therefore, the topical developments in the synthesis, working, and application of MI-FCDs for sensing various target species (e.g., pharmaceuticals, biomolecules, pesticides, food additives, and miscellaneous species) in food and biological media have been highlighted. Moreover, a careful evaluation has been made to select the best methods based on their performance in terms of analytical parameters. To expand the horizons of this field, important challenges and future directions for developing MI-FCDs for practical use are also presented. This review will highlight important aspects of MI-FCDs-based fluorescent sensors for their applicability in food science, material science, environmental science, nanoscience, and biotechnology. Highlights: Fabrication of MI-FCDs probes with sensing properties. Recognition ability of MI-FCDs via single or dual emission detection. Important sensing applications in food and biological samples. Comparison of performance of MI-FCDs based on analytical parameters. Discussion on challenges and future trends of MI-FCDs probes. [ABSTRACT FROM AUTHOR]

As a commonly well-known industrial chemical, phthalates are produced in high volumes to be used in various consumer products (e.g., plasticizers, medical devices, construction materials, and toys) to enhance softness, durability, transparency, and flexibility. Phthalates are generally not chemically bonded to the polymer chain of the plastic in which they are mixed. Thus, they may leach, migrate, or evaporate into indoor/outdoor air, and foodstuffs. In this review, a comprehensive overview of several sample preparation methods coupled with gas chromatography for the analysis of phthalates in various kinds of complex matrices, with a focus on the last 20 years' worth of papers. The review begins by highlighting the environmental significance of phthalate pollution along with the various routes to their exposure to general population. Then, the discussion is extended to cover the pretreatment and extraction techniques for phthalates for their quantitation based on gas chromatographic approach. Finally, the present and future challenges for the detection of phthalates in aqueous and food matrices are discussed. [ABSTRACT FROM AUTHOR]

This study presents a new and rapid analytical high‐performance liquid chromatography coupled with a photodiode array detector method for determining nickel ion (Ni2+) complex with Schiff base (Z)‐1‐(thiophen‐2‐yl‐methyleneamino) propane‐2‐ol easily. The influence of pH, surfactant, and effect of mobile phase on the formation of the Ni‐(Z)‐1‐(thiophen‐2‐yl‐methyleneamino)propane‐2‐ol complex was studied and optimized. The results showed that the acidic condition (pH = 5) favors the complexation most. Triton X‐100 neutral surfactant was used for dissolving the Ni–complex synthesized. A mobile phase ratio of methanol:acetonitrile:water 70:20:10, v/v/v was taken as optimum. This approach allowed the analysis of Ni2+ ion with the limit of detection of 0.0349 ng/mL over the linear range of (0.1–250 ng/mL) and a relative standard deviation of < 2%. The developed method exhibited remarkable extraction recoveries for Ni2+ in various real water samples (tap water; 98.0%–99.8% and river water; 97.0%–98.7%) and alloys with recoveries of (nichrome; 85.2% and chromel; 88.4%). Moreover, this protocol was also applied for the quantitation of Ni2+ in real sewage samples at a concentration level of 0.256 ng/mL. The outcomes of the present work successfully revealed the apparent superiority of Schiff base (Z)‐1‐(thiophen‐2‐yl‐methyleneamino) propane‐2‐ol toward the practical removal of target Ni2+ under real‐world conditions. [ABSTRACT FROM AUTHOR]

A Schiff base bis(thiophen-2-yl-methylene)benzene-1, 4-diamine (L) was synthesized and used for selective and sensitive detection of Fe3+. L exhibited enhanced fluorescence response at excitation of 365 nm and emission wavelength of 440 nm for Fe3+. The formation of a 1:1 complex between L and Fe3+ was suggested by Job's plot by fluorescence titration and from optimized structures using Density functional theory (DFT). The fluorescence intensity was directly proportional to concentration of Fe3+ (R2 = 0.999) with the detection limit of 3.8 × 10–7 M and the binding constant of 1.20 × 104 M−1 at pH = 6.0. The probe was used to detect Fe3+ in different water samples with the percentage recovery of 99.7–103%. The interference of the other cations are < 5%. [ABSTRACT FROM AUTHOR]

Background: A large variety of inflammatory and neoplastic lesions are known to occur within internal auditory canal and cerebellopontine angle. Imaging techniques are now available to guide the search for the underlying cause of most patient complaints. The advent of MRI has revolutionized the medical diagnostic imaging because it allowed tissue characterization of many lesions. High resolution MRI scan is highly sensitive in detecting lesions of internal auditory canal and cerebellopontine angle. More recently, diffusion imaging is playing a substantial role in evaluation of CPA masses. High ADC values of solid vestibular schwannomas were in conformity with increased diffusion rates, indicating the presence of increased amounts of extracellular water (a relatively loose tissue in tumor matrix). This study was undertaken with purpose to present MRI findings in cases of CPA and IAC lesions and to assess the impact of MRI on the diagnosis management and follow up, after treatment, of these lesions with an attempt to compare MRI findings with operative and H/P findings in the cases where surgery was done. Materials and methods: The present study was conducted in Post Graduate Department of Radiodiagnosis, Government Medical College, Srinagar on patients presenting with otoneurological signs and symptoms suggestive of CP angle and IAC lesions referred for MR imaging by various departments of GMC Hospital Srinagar during the one year period of study. Results: Majority of lesions found in this study were tumors (33 lesions), next common in our series were inflammatory lesions and vascular lesions (4 each case). Among all lesions and tumors most common MR diagnosis in our study was acoustic neuroma 20 of 41 lesions (48.78%) and 20of 33 tumors (60.60%) respectively. Next common among tumors was meningiomas 3 out of 33 cases (9.09%). Conclusion: The results of the present study concluded that, MRI has particular advantages over CT for study of internal auditory canal and cerebellopontine lesions because it is non-ionizing investigation, better soft tissue contrast and resolution, multiplanar capability permits more reliable distinction of lesions, better identification of structures involved by lesions, tissue characterization of lesions and absence of beam hardening artifacts makes MR imaging superior ion evaluating the lesions in CP angle and IAC. The radiological features of various lesions are often sufficiently distinctive to permit a specific diagnosis to be made. MR imaging due to its multiplanar capability helps in knowing the exact site and extent of these lesions. MRI shows inflammatory and vascular lesions with exquisite detail and is better for detection of such lesions as compared to CT. MRI allows a confident perspective pathologic diagnosis to be made (Using FSE T2 weighted images, diffusion imaging, SE images, thin section post gadolinium scans) and this predictive value far exceeded the CT. [ABSTRACT FROM AUTHOR]

The incidence of prostate cancer has been gradually increasing in the world. Checking the serum prostate-specific antigen (PSA) level and a digital rectal examination (DRE) are the gold standards for prostate cancer screening. Prostate gland is divided into four zones, the peripheral zone (PZ), transitional zone and central zone and anterior nonglandular fibromuscular stroma. Prostate is divided into minimum 16 and optionally 27 regions of interest as per European consensus meeting. Until recently, most professionals have been skeptical that magnetic resonance imaging (MRI) could be used on a widespread basis to diagnose or stage prostate cancer with any degree of reliability, and therefore help with making treatment decisions. The aim of the present study was to study diagnostic value of mpMRI of prostate in cases of raised PSA but with negative biopsy. The present study was carried out in the post graduate department of Radiodiagnosis and imaging Govt. Medical College Srinagar over a period of one year from May 2016 to April 2017. All patients with negative prostatic biopsy were evaluated on Siemens 3 tesla MRI scanner. All patients underwent initial T1W scanning to look for any evidence of hemorrhage and patients having hemorrhage due to previous biopsy were also excluded from study or their study was deferred until hemorrhagic artifacts disappear. After proper case selection patients were subjected to detail Multiparametric MRI (mpMRI) for prostate 6-8 weeks period was given from previous biopsy time to MRI study and cases with hemorrhage on T1 weighted sequence were either excluded from study or their study was deferred till resolution of haemorrhage. The conclusion of the present study was that Mp-MRI prior to repeat biopsies can improve the detection rate of clinically significant PCa and allow for a more accuracy in prostate disease diagnosis. [ABSTRACT FROM AUTHOR]

A tripodal amine (TPA) with -OH, N, and S donors is synthesized to functionalize a core-shell carbon dot composite (FCDs@SiO 2 -TPA) for sensing application. The TPA is characterized by spectroscopic and spectrometric techniques, and the composite is characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectra (EDS) techniques. The composite has the ability to recognize mefenamic acid (MFA) selectively even in the presence of other drugs like ibuprofen sodium, acetylsalicylic acid, naproxen sodium, diclofenac sodium, and ketoprofen. It can also be used for the quantification of MFA by recording the emission quenching response of the sample at λ exc. = 350 nm and λ ems. = 460 nm (linear range = 1-8 μM and LOD = 197 nM). The density functional theory calculations and 1 H NMR titration suggest quenching of the emission signal due to photoinduced electron transfer via hydrogen bonding between the probe and MFA. The composite FCDs@SiO 2 -TPA has been demonstrated as a reliable and cost-effective sensing probe for the detection of MFA in pharmaceutical formulations, water samples, and cow urine samples.