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A noninvasive detection technique of diabetes via monitoring the concentration of acetone in exhaled breath (EB) has been approaching to groundbreaking innovations in the very recent years (2008–2018). Not only various methods of detection have been studied but also the performance of several functional materials has been investigated in this application, and in the current decade further attention has been given to the engineering aspects of devising a cost-effective hand-held ‘exhaled breath acetone detector’ (EBAD). Considering the rapid growth of advanced technology in recent years on devising a robust EBAD, this review is aimed to present a footnote on the major progress and prospects of EBAD ongoing in the current decade. This review exemplifies that an EBAD could potentially become a supplementary device with the conventional glucometer by the end of this decade and will eliminate the need for the continuous blood test for diabetes patients.

In this fundamental research, we found that homo-oligo based dsDNA holds potential electrochemical characteristics in comparison to hetero-oligo based dsDNA which can be exploited in voltammetric and impedimetric biosensors. We prepared a homo-oligo based dsDNA from 20 deoxyribonucleotides of adenine, guanine, cytosine, and thymine (A20, G20, C20, and T20 respectively) and a hetero-oligo based dsDNA from two partially complementary oligos (5′-TTT TTT CAT CTA TCA ACA TCA GTC TGA TAA GCT ATA GAA GC-3′ and 5′-TTT TTT ATA GCT TTG ATA GA-3’. Electrochemical impedance spectroscopy in 1 mM 0.1 M K3[Fe(CN)6]/KCl showed that Au working electrode modified with hetero-oligo based dsDNA (Au/hetero-oligo-dsDNA) was more resistive toward charge transfer of Fe(CN)63−/4- compared to Au working electrode modified with homo-oligo based dsDNA (Au/homo-oligo-dsDNA). Additionally, cyclic voltammetry and linear sweep voltammetry showed that Au/homo-oligo-dsDNA produced quantifiable anodic and cathodic peak currents which were not observed for Au/hetero-oligo-dsDNA. Nyquist and Bode plots derived from electrochemical impedance spectroscopy on three different electroactive areas (0.0705, 0.0747 and 0.0837 cm2) of Au working electrode showed no significant change in the capacitive behavior of Au/homo-oligo-dsDNA and Au/hetero-oligo-dsDNA in a linear range of frequency (10–100 Hz).

A green and clean approach that requires low energy and avoids the use of any toxic or corrosive reagents/solvents for the synthesis of potential fullerenol moieties [C60(OH)n·mH2O] was proposed in this investigation, in which pristine fullerene (C60) in dil. H2O2 (30%) aqueous media was ultrasonicated (20 kHz, 200 W) at 30% amplitude for 1 h. The attachment of hydroxyl groups (–OH) was investigated via FTIR and the quantification of –OH groups attached to the C60 cage was conducted via elemental analysis. The number of secondary bound water molecules (mH2O) with each fullerenol molecule [C60(OH)n] was measured via TGA, and the estimated average structure of fullerenol was calculated to be C60(OH)8·2H2O. The synthesized fullerenol was moderately soluble in water and DMSO. Furthermore, the size of the synthesized C60(OH)8·2H2O particles determined by both AFM and DLS analysis was found to be in the range of 135–155 nm. The proposed ultrasound-assisted acoustic cavitation technique encompasses a one-step facile reaction strategy, requires less time for the reaction, and reduces the number of solvents required for the separation and purification of C60(OH)8·2H2O, which could be scalable for the commercial synthesis of fullerenol moieties in the future.

Purpose: This project was aimed to determine the effect of concurrent administration of sulfamethoxazole and diclofenac sodium. Methods: Equilibrium dialysis method was adopted to study different protein binding aspects of sulfamethoxazole and diclofenac sodium. Results: Sulfamethoxazole showed two types of association constants; high affinity constant 29.0±0.20×106 M-1 with lower number of binding sites of 0.7±1 and low affinity constant 1.13±0.20×106 M-1 with higher number of binding sites of 3.45±1 at pH 7.4 and 40 °C temperature. Diclofenac sodium showed high affinity constant 33.66±0.20×106 M-1 with lower number of binding sites of 1.01±1 and low affinity constant 1.72±0.20×106 M-1 with higher number of binding sites of 6.40±1 at the same condition. Site specific probe displacement data implied that site-I, warfarin sodium site, was the high affinity site, while site-II, diazepam site, was the low affinity site for these drugs. During concurrent administration, sulfamethoxazole increased the free concentration of diclofenac sodium from 17.5±0.14% to 70.0±0.014% in absence and from 22.5±0.07% to 83.0±0.014% in presence of site-I specific probe. Diclofenac sodium also increased the free concentration of sulfamethoxazole from 2.8±0.07% to 52.0±0.14% and from 8.5±0.014% to 64.4±0.07% in absence and presence of site-I specific probe respectively. Conclusions: The study revealed that the concurrent administration of sulfamethoxazole and diclofenac sodium may result drug concentration alteration in blood.

The main objective of this review is to derive the salient features of previously developed ultrasound-assisted methods for hydroxylating graphene and Buckminsterfullerene (C60). The pros and cons associated to ultrasound-assisted synthesis of hydroxy-carbon nanomaterials in designing the strategical methods for the industrial bulk production are also discussed. A guideline on the statistical methods has also been considered to further provide the scopes towards the application of the previously reported methods. Irrespective of many useful methods that have been developed in order to functionalize C60 and graphene by diverse oxygenated functional groups e.g. epoxide, hydroxyl, carboxyl as well as metal/metal oxide via a combination of organic chemistry and sonochemistry, there is no report dealing exclusively on the application of ultrasonic cavitation particularly to synthesising polyhydroxylated carbon nanomaterials. On this context, this review emphasizes in investigating the critical aspects of sono-nanochemistry and the statistical approaches to optimize the variables in the sonochemical process towards a large-scale synthesis of polyhydroxylated graphene and C60.

Glassy carbon particles (millimetric or micrometric sizes) dispersions in water were treated by ultrasound at 20kHz, either in a cylindrical reactor, or in a "Rosette" type reactor, for various time lengths ranging from 3h to 10h. Further separations sedimentation allowed obtaining few nanoparticles of glassy carbon in the supernatant (diameter