Development of highly sensitive electrochemical immunosensor using PPy-MoS2-based nanocomposites modified with 90 MeV C6+ ion beams

The evaluation of electrochemical sensing activity of hydrothermally derived PPy-MoS2-based nanocomposites subjected to 90 MeV C6+ ion beam with fluence ranging, 1.0 × 1010-1.0 × 1013 ions/cm2, is reported. Cross-linking, chain scissioning, and ion track formation could occur in the irradiated systems, as revealed from Fourier transform infrared (FTIR) spectroscopy and field emission scanning electron microscopy (FE-SEM) studies. Electrochemical studies, viz., cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were performed in 0.1 M phosphate buffer solution (PBS) containing 5 mM K3[Fe(CN)6] as redox probe. High redox activity, lower charge transfer resistance (Rct = 490 Ω) and larger electroactive area (A = 0.4485 cm2) were obtained in case of the composite system irradiated with a fluence of 3.5 × 1011 ions/cm2. Immunosensor fabrication was executed via immobilization of mouse IgG over the pristine and post-irradiated electrodes. Afterwards, differential pulse voltammetry (DPV) was performed within the potential window - 0.2 to + 0.6 V (vs. Ag/AgCl) for the detection of specific analyte. Noticeably, the electrode system irradiated with a fluence of 3.5 × 1011 ions/cm2 is characterized by a lower limit of detection (LOD) of 0.203 nM and a higher sensitivity value of 10.0 µA mL ng-1 cm-2. The energetic particle irradiation at a modest fluence can offer beneficial effects to the PPy-MoS2-based nanohybrid system providing immense scope as advanced electrochemical biosensor.

Electrochemically deposited bimetallic SERS substrate for trace sensing of antibiotics

Electrochemically deposited bimetallic copper-gold nanoparticles on indium tin oxide (Cu-AuNPs on ITO) glass are demonstrated to be a sensitive and reproducible surface-enhanced Raman scattering (SERS) platform. An optimal signal enhancement with reasonably good degree of homogeneity was obtained by tuning the deposition parameters of the electrochemical setup. For Raman active analytes such as malachite green (MG) and rhodamine 6G (R6G), the developed SERS platform yields a limit of detection (LOD) of 0.75 nM. The usability of the proposed SERS platform has been realized through detection of two important antibiotics namely sulfamethoxazole (SFZ) and tetracycline hydrochloride (TCH) commonly used in egg farms. Furthermore, a machine learning (ML)-based model coupled with a dimensionality reduction technique-principal component analysis (PCA)-has been implemented to classify the targeted analytes in egg samples.

First results of a clinical pilot study on intraarterial chemotherapy with haemofiltration of locally advanced gastrointestinal cancers

Intra-arterial chemotherapy combined with haemofiltration enables the administration of drugs to confined neoplastic tissue while limiting the systemic drug exposure. During the procedure, the cytotoxic drugs are injected into the arterial supply of the tumour and the venous blood coming from the tumour bed is pumped out and filtered trough haemofiltration unit in order to extract the cytotoxic drug not fixed on the tumour. The patients selected for such treatment failed previous intravenous chemotherapy. Thirteen patients underwent intra-arterial chemotherapy injections combined with haemofiltration procedures: 8 unresectable liver metastases from colorectal cancer and 5 pelvic recurrences from rectal cancer. Fluorouracil, mitomycin C and doxorubicin were infused. One out of thirteen patients presented a complete regression of his liver metastases, 5/13 presented a partial regression, 2/13 patients did not show any significant modification of the size of their lesions and were classified as stable disease, 5/13 patients showed a progression of their neoplastic disease. No nephrotoxicity or major gastrointestinal side effects were observed. Intra-arterial chemotherapy combined with haemofiltration procedure is a therapeutic modality that could be considered in patients with locally advanced cancer who failed previous first line intravenous chemotherapy.