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We present a simple in situ self-assembly approach for crafting a heteroatom doped graphene supported metal–organic framework (MOF) nanocomposite, which is a highly conductive redox active 2D platform with excellent potential for selective and sensitive electrochemical sensing of biologically important molecules. The hybrid nanocomposite comprises of 1,4-benzene dicarboxylic acid organic linker based Cu-MOF self-assembled over sulfur doped graphene nanosheets (S-Gr). Our detailed structural characterization and electrochemical investigations carried over the so-crafted Cu-MOF@S-Gr composite suggest that S-Gr sheets, besides inducing a directional growth of MOF crystals, endow this nanohybrid with numerous electroactive sites. The synergism between the Cu-MOF and S-Gr components and the presence of too many electroactive sites facilitate faster heterogeneous electron transfer and mass transfer, thereby imparting Cu-MOF@S-Gr with excellent conductivity, electrocatalytic activity and electroanalytical utility. The excellent electroanalytical utility of the Cu-MOF@S-Gr hybrid nanocomposite was explored toward selective and sensitive sensing of acetaminophen (AC), dopamine (DA) and H2O2. We demonstrate that using the Cu-MOF@S-Gr hybrid nanocomposite, AC and DA can be electrochemically sensed with a resolution of 2.22 and a sensitivity of 0.85 μA μM−1 cm−2 and 0.58 μA μM−1 cm−2 in the concentration ranges of 2 μM to 98 μM and 10 μM to 80 μM with detection limits as low as 12.00 ± 0.05 nM and 37.00 ± 0.06 nM, respectively. We also demonstrate that with the Cu-MOF@S-Gr hybrid, H2O2 can be electrochemically sensed in the concentration range as low as 0.1–3.0 μM with an extremely low detection limit of 11.3 ± 0.04 nM and a very high sensitivity of 63.82 μA μM−1 cm−2. We opine that the present study will stimulate an intense research activity toward the design of highly sensitive, selective and stable MOF based electroanalytical devices. [ABSTRACT FROM AUTHOR]

We report the synthesis of a nano-spinel cobalt decorated sulphur doped reduced graphene oxide (Co@S–rGO) composite exhibiting excellent electrocatalytic performance and electrochemical stability toward oxygen evolution reaction (OER) in an alkaline medium. Moreover, the so crafted noble metal free Co@S–rGO electrocatalyst, well characterized by UV-Vis spectroscopy, FTIR, XRD, SEM, and energy dispersive X-ray spectroscopy, exhibits promising activity toward electrochemical sensing of H2O2. For OER in an alkaline medium, the Co@S–rGO composite exhibits a Tafel slope of ca. 49 mV dec−1, with an overpotential requirement of just 389 mV for a specific current density of 10 mA cm−2. In the OER electrochemical stability tests, the Co@S–rGO electrocatalyst could maintain its peak OER performance for a time span of about 50 000 seconds during chronoamperometric measurements, while in the linear sweep voltammetry records almost negligible difference was observed between the final and the initial scan in a total of 1000 scans recorded over 25 hours for OER over Co@S–rGO. These chronoamperometric and voltammetric observations establish the excellent activity and long-term electrochemical stability of Co@S–rGO for OER in alkaline media. These current/potential and stability parameters observed for the OER performance of the Co@S–rGO composite are far better than that reported for various non-noble metal based state-of-the-art materials specifically crafted for OER. For the electrochemical sensing of H2O2, the Co@S–rGO composite exhibits a limit of detection as low as 23 nM with a sensitivity of 22743.85 μA M−1 cm−2. The excellent OER performance and H2O2 sensing activity of the Co@S–rGO composite can be attributed to the special synergism between the Co and S–rGO components and the extended electrochemically active surface area of Co nanodeposits in this noble metal free electrocatalyst. [ABSTRACT FROM AUTHOR]

Osteomyelitis is an inflammatory disease of the bone that usually begins as an infection of themedullary cavity, rapidly involves the haversian system, and quickly extends to the periosteum of the area. It develops in the jaws after a chronic odontogenic infection or for a variety of other reasons such as trauma, inadequate treatment of fracture, or irradiation to the mandible. When antimicrobial agents or drainage prove unsuccessful, acute osteomyelitis may become chronic. Conventional radiography, culture, bone biopsy, radioisotope bone scan, laser Doppler flowmetry, computed tomography, and magnetic resonance imaging are used for its diagnosis. We present a case of chronic suppurative osteomyelitis associated with a draining extraoral sinus, which was successfully treated with surgical debridement and stabilization with a 12-hole reconstructionplate and bicortical screws using AO principles. [ABSTRACT FROM AUTHOR]

Here, we report the enhanced photoelectrochemical performance of surface modified hematite thin films with n-type copper oxide nanostructures (Cu2O/Fe2O3) obtained through simple electrochemical deposition method. The thickness and amount of cuprous oxide layer were varied by simply changing the number of electrodeposition cycles (viz. 5, 10, 25, 50 and 100) in order to understand its thermodynamic and kinetic influence on the photoelectrochemical activity of the resultant nano-heterostructures. Structural and morphological characteristics of the obtained Cu2O/Fe2O3 films have been studied by absorption spectroscopy, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analysis. Electrochemical investigations such as linear sweep voltammetry, Mott-Schottky analysis, and electrochemical impedance spectroscopy suggested the formation of n-type Cu2O layers over the hematite films with varying charge-carrier densities, ranging from 0.56 × 1019 to 3.94 × 1019 cm-3, that varies with the number of cycles of electrochemical deposition. Besides, the thickness of deposited cuprous oxide layer is noted to alter the net electrochemical and photo-electrochemical response of the base material. An interesting, peak event was recorded for a particular thickness of the cuprous oxide layer (obtained after 25 cycles of electrochemical deposition) below and above which the efficiency of catalyst was impaired. The heterojunction obtained thus, followed well known Z-scheme and gave appreciable increment in the photocurrent response. [ABSTRACT FROM AUTHOR]

Trigeminal neuralgia or tic douloureux is a commonly diagnosed oro-facial pain syndrome. It is characterized by sudden, usually unilateral, severe, brief, stabbing, lancinating, paroxysmal, recurring pain in the distribution of one or more branches of the fifth cranial nerve. It occurs more commonly in females, with peak occurrence seen in the age group of above 50 years. Multiple views have been hypothecated regarding its aetiology. Peripheral neurectomy is the safest and simplest method that can be accomplished under local anaesthesia with minimum risks and excellent pain relief to the patient. [ABSTRACT FROM AUTHOR]

Palatal fistula may lead to various clinical problems such as nasal air escape, speech distortion, hearing loss, or fluid and food regurgitation. Most of the ONF are situated at the junction of hard and soft palate and its repair depends on the site, size and mode of presentation. The management of palatal defects results from the oronasal communication by a variety of methods such as buccal flap, palatal flap and tongue flap. These optimal techniques allow maximal postoperative function with minimal morbidity. [ABSTRACT FROM AUTHOR]

A simple strategy for the synthesis of self-assembled gold nanoparticles (AuNPs) on sulphur-doped graphene (S-Gr) to form AuNPs-S-Gr nanohybrids is presented. Structural, chemical and morphological characterization of AuNPs-S-Gr nanohybrids through UV-Vis spectroscopy, the X-ray diffraction technique (XRD), Raman spectroscopy, force field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high-resolution TEM (HR-TEM) and electrochemical techniques establishes the AuNPs-S-Gr nanohybrid as a monolayer of AuNPs assembled on S-Gr. The lead underpotential deposition experiments ascertain that nano Au in AuNPs-S-Gr nanohybrids is better exposed for faradic processes than in citrate-stabilized AuNPs, with the faradic response in the former being dominated by the Au-(111) planes. The AuNPs-S-Gr nanohybrids are demonstrated to be electrochemically stable, reusable and with an excellent prospect for the sensitive and selective electrochemical detection of two biologically and environmentally important oxides of nitrogen viz. nitrite (NO2−) and nitric oxide (NO). The electrocatalytic electron transfer rate constants (kcat) of the AuNPs-S-Gr nanohybrid towards electro-oxidation of NO2− and NO were observed to be 0.98 (±0.03) × 105 M−1 s−1/2 and 0.51 (±0.02) × 104 M−1 s−1/2, respectively. The AuNPs-S-Gr nanohybrid was demonstrated to ensure selective and sensitive electrochemical quantification of NO2− and NO with a very high sensitivity (20766.17 and 21046.72 μA M−1 cm−2), a wide linear range (12.5–680.92 and 24.9–680.93 μM) and very low detection limits (0.003 and 0.009 μM), respectively. Importantly, the AuNPs-S-Gr nanohybrid exhibited appreciable selectivity towards the detection of NO2− and NO even in the presence of a very high concentration of common interfering ions. The stability and reproducibility of faradic signals for NO2− and NO detection at the AuNPs-S-Gr nanohybrid were found to be excellent for standard laboratory and real samples. The electrocatalytic activity and sensing results of the AuNPs-S-Gr nanohybrid for NO2− and NO are much better than those recently reported over surfaces purposefully designed for electrocatalytic oxidation and electrosensing of these analytes. [ABSTRACT FROM AUTHOR]

We present a simple in situ self-assembly approach for crafting a heteroatom doped graphene supported metal–organic framework (MOF) nanocomposite, which is a highly conductive redox active 2D platform with excellent potential for selective and sensitive electrochemical sensing of biologically important molecules. The hybrid nanocomposite comprises of 1,4-benzene dicarboxylic acid organic linker based Cu-MOF self-assembled over sulfur doped graphene nanosheets (S-Gr). Our detailed structural characterization and electrochemical investigations carried over the so-crafted Cu-MOF@S-Gr composite suggest that S-Gr sheets, besides inducing a directional growth of MOF crystals, endow this nanohybrid with numerous electroactive sites. The synergism between the Cu-MOF and S-Gr components and the presence of too many electroactive sites facilitate faster heterogeneous electron transfer and mass transfer, thereby imparting Cu-MOF@S-Gr with excellent conductivity, electrocatalytic activity and electroanalytical utility. The excellent electroanalytical utility of the Cu-MOF@S-Gr hybrid nanocomposite was explored toward selective and sensitive sensing of acetaminophen (AC), dopamine (DA) and H2O2. We demonstrate that using the Cu-MOF@S-Gr hybrid nanocomposite, AC and DA can be electrochemically sensed with a resolution of 2.22 and a sensitivity of 0.85 μA μM−1 cm−2 and 0.58 μA μM−1 cm−2 in the concentration ranges of 2 μM to 98 μM and 10 μM to 80 μM with detection limits as low as 12.00 ± 0.05 nM and 37.00 ± 0.06 nM, respectively. We also demonstrate that with the Cu-MOF@S-Gr hybrid, H2O2 can be electrochemically sensed in the concentration range as low as 0.1–3.0 μM with an extremely low detection limit of 11.3 ± 0.04 nM and a very high sensitivity of 63.82 μA μM−1 cm−2. We opine that the present study will stimulate an intense research activity toward the design of highly sensitive, selective and stable MOF based electroanalytical devices. [ABSTRACT FROM AUTHOR]

We report the synthesis of a nano-spinel cobalt decorated sulphur doped reduced graphene oxide (Co@S–rGO) composite exhibiting excellent electrocatalytic performance and electrochemical stability toward oxygen evolution reaction (OER) in an alkaline medium. Moreover, the so crafted noble metal free Co@S–rGO electrocatalyst, well characterized by UV-Vis spectroscopy, FTIR, XRD, SEM, and energy dispersive X-ray spectroscopy, exhibits promising activity toward electrochemical sensing of H2O2. For OER in an alkaline medium, the Co@S–rGO composite exhibits a Tafel slope of ca. 49 mV dec−1, with an overpotential requirement of just 389 mV for a specific current density of 10 mA cm−2. In the OER electrochemical stability tests, the Co@S–rGO electrocatalyst could maintain its peak OER performance for a time span of about 50 000 seconds during chronoamperometric measurements, while in the linear sweep voltammetry records almost negligible difference was observed between the final and the initial scan in a total of 1000 scans recorded over 25 hours for OER over Co@S–rGO. These chronoamperometric and voltammetric observations establish the excellent activity and long-term electrochemical stability of Co@S–rGO for OER in alkaline media. These current/potential and stability parameters observed for the OER performance of the Co@S–rGO composite are far better than that reported for various non-noble metal based state-of-the-art materials specifically crafted for OER. For the electrochemical sensing of H2O2, the Co@S–rGO composite exhibits a limit of detection as low as 23 nM with a sensitivity of 22743.85 μA M−1 cm−2. The excellent OER performance and H2O2 sensing activity of the Co@S–rGO composite can be attributed to the special synergism between the Co and S–rGO components and the extended electrochemically active surface area of Co nanodeposits in this noble metal free electrocatalyst. [ABSTRACT FROM AUTHOR]

Here, we present fabrication of Graphene oxide (GO) supported Cu/Cu x O nano-electrodeposits which can efficiently and selectively electroreduce CO 2 into ethylene with a faradaic efficiency (F.E) of 34% and a conversion rate of 194 mmol g -1 h -1 at -0.985 V vs. RHE. The effect of catalyst morphology, working electrode fabricational techniques, the extent of metal-GO interaction and the oxide content in Cu/Cu x O, was studied in detail so as to develop a protocol for the fabrication of an active, stable and selective catalyst for efficient electro-production of ethylene from CO 2 . Moreover, a detailed comparative study about the effect of the GO support, and the nature of the cathodic collection substrate used for the electro-deposition is presented., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)