Ni-doped MoS 2 thin films were fabricated by electrodeposition from electrolytes containing both MoS 4 2− and varying concentrations of Ni 2+ , followed by annealing at 400 °C for 2 h in an Ar atmosphere. The film resistivity decreased from 32.8 μΩ-cm for un-doped MoS 2 to 11.3 μΩ-cm for Ni-doped MoS 2 containing 9 atom% Ni. For all Ni dopant levels studied, only the X-ray diffraction (XRD) pattern expected for MoS 2 is observed, with the average grain size increasing with increasing Ni content. Ni-doped MoS 2 thin films were tested for their activity towards the hydrogen evolution reaction (HER) in 0.5 M H 2 SO 4 . Tafel equation fits reveal that the catalytic activity for the HER, as measured by the exchange current density, increases up to 6 atom% Ni, and then decreases slightly for 9 atom% Ni. Ni-doped MoS 2 thin films were also tested in 1.0 M Na 2 SO 4 for use within electrochemical supercapacitors, and the capacitance per unit area increases by 2-3x for 9 atom% Ni-doped MoS 2 relative to undoped MoS 2 . The highest capacitance obtained for Ni-doped MoS 2 during galvanostatic charge-discharge measurements is ∼300 F g −1 .

Despite high prevalence and incidence of β-thalassemia in Pakistan, there is very limited work on the use of hydroxyurea (HU) in thalassemia patients in the country. This is the first insight regarding genetic profiling of BCL11A and HU responses in Pakistani β-thalassemia. It correlates single-nucleotide polymorphisms on BCL11A (rs4671393, rs766432) and HBG2 (XmnI), age at first transfusion, and β-globin mutations with HU response in β-thalassemia major (BTM). Of 272 patients treated with HU, 98 were complete responders, 55 partial responders, and 119 nonresponders. Our analysis shows that HU response was significantly associated with patients having IVSI-1 or CD 30 mutation (P < 0.001), age at first transfusion > 1 year (P < 0.001), and with the presence of XmnI polymorphism (P < 0.001). The single-nucleotide polymorphisms of BCL11A were more prevalent among responders, but could not show significant association with HU response (P > 0.05). Cumulative effect of all 5 predicting factors through simple binary scoring indicates that the likelihood of HU response increases with the number of primary and secondary genetic modifiers (P < 0.001). Predictors scoring is a pragmatic tool to foresee HU response in patients with BTM. The authors recommend a score of ≥ 2 for starting HU therapy in Pakistani patients with BTM.

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Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disorder, which has complex diagnostic steps. Electrochemical immunoassays may make the diagnosis simpler and faster. Here, we present the detection of ALS-associated neurofilament light chain (Nf-L) protein through an electrochemical impedance immunoassay on reduced graphene oxide (rGO) screen-printed electrodes. The immunoassay was developed in two different media, i.e., buffer and human serum, to compare the effect of the media on their figures of merit and calibration models. The label-free charge transfer resistance (RCT) of the immunoplatform was used as a signal response to develop the calibration models. We found that exposure of the biorecognition layer to human serum improved the impedance response of the biorecognition element with significantly lower relative error. Moreover, the calibration model obtained in the human serum environment has higher sensitivity and a better limit of detection (0.087 ng/mL) than the buffer medium (0.39 ng/mL). The analyses of the ALS patient samples show that concentrations obtained from the buffer-based regression model was higher than the serum-based model. However, a high Pearson correlation (r = 1.00) between the media suggests that concentration in one medium may be useful to predict the concentration in the other medium. Moreover, the Nf-L concentration appears to increase with age in both male and female groups, while overall higher Nf-L was found in the male group than the female group.

This study presents the fabrication of the first multiplexed wax-on-plastic electrochemical chip with low-temperature sintering of the conductive layers. A total of 169 sensing electrodes (1.2 mm diameter each) were printed on a wax-patterned plastic substrate using silver inkjet printing. Fidelity of the device was confirmed using optical and electrical techniques. The sensing electrodes were modified using graphene oxide (GO) ink and peptide nucleic acid (PNA) probes through simple drop-casting. The PNA/GO interface on the multiplexed chip was used to detect DNA using differential pulse voltammetry, which records the electrons transfer from the diffusion of a soluble redox probe. The PNA/GO interface was then tested against a target concentration, target size, and mismatched target. The response of the DNA-PNA duplex on the surface was additionally compared with the prehybridized duplex, and the lower affinity of the duplexes for the GO surface was confirmed by removing Mg2+. The interface was responsive to such variables at attomolar concentrations. The low volume of the target (300 nL) at that concentration level demonstrated the chip sensitivity with only 18 target molecules on the surface.