Finding novel strategies for surface modification is of great interest in electrochemistry and material sciences. In this study, we present a strategy for modification of a gold electrode through covalent attachment of triazole (TA) groups. Triazole groups were electrochemically grafted at the surface of the electrode by a reduction of in situ generated triazolediazonium cations. The resulting grafted surface was characterized before and after the functionalization process by different electrochemical methods (cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS)) confirming the presence of the grafted layer. The grafting of TA on the electrode surface was confirmed using analysis of surface morphology (by atomic force microscopy), the thickness of the grafted layer (by ellipsometry) and its composition (by X-ray photoelectron spectroscopy). Density functional theory (DFT) calculations imply that the grafted triazole offers a stronger platform than the grafted aryl layers.

Surface modification of gold is accomplished by using the aminyl radicals formed through the electrochemical oxidation of the amino-triazole molecule dissolved in organic media (acetonitrile).

Neonatal hyperoxia increases contraction and decreases the relaxation of airway smooth muscle (ASM), and the balance between these processes in airways is critical for normal flow of air. Thus, it is important to search for an effective treatment that targets this balance to prevent the airway hyperreactivity. The non-adrenergic- noncholinergic inhibitory system mediators such as vasoactive intestinal peptide (VIP) play an important role in ASM tone. Therefore, we tested the hypothesis that exogenous VIP will reverse the impaired relaxation of tracheal smooth muscle exposed to neonatal hyperoxia. Tracheal cylinders were obtained from Wistar rat pups (P10) exposed to hyperoxia (≥ 95% O2) or room air for seven days. These cylinders were used to study relaxant responses of tracheal smooth muscle (TSM) evoked by electrical field relaxation (EFS) in precontracted tissue (carbachol, 10μM) in absence or presence of a single dose of VIP (50 nM). In addition, the dose-response relaxant effect of VIP (1nM – 1μM) was tested in absence or presence of a VPAC receptor antagonist; a protein kinase A (PKA) inhibitor (Rp-8-CPT-cAMPS); a phosphodiesterase 4 (PDE4) inhibitor (rolipram); or a large-conductance calcium-activated potassium channel blocker (charybdotoxin). The relaxation is expressed as percentage of preconstricted state, and data are presented as mean±s.e.m. Hyperoxic exposure significantly decreased the relaxation of TSM towards EFS, as compared to those obtained from control animals exposed to room air, and these impaired relaxant responses in hyperoxic preparations were significantly reversed in presence of VIP (p<0.01). VIP induced dose-dependent relaxation and the relaxant responses were overcompensated in hyperoxic animals. VPAC antagonist; PKA or PDE4 inhibition significantly reduced VIP-induced relaxation (p<0.05), while blockade of calcium-activated potassium channel did not have significant effect.The results of this study revealed that VIP reverses the impaired relaxation of airway smooth muscle induced by hyperoxic exposure via cAMP/PKA signaling pathway and we speculate that the use of VIP might be an effective therapeutic approach to prevent the airway hyperreactivity induced by hyperoxia. Supported by the Ministry of Education, Science, and Technology of the Republic of Kosovo - Small Research Grants: 2-2459-11. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Abstract. Alprazolam is a widely prescribed sedative and antidepressant benzodiazepine (BDZ) drug which belongs to the class of anxiolytic, sedative and hypnotic anticonvulsants. It is believed that alprazolam (ALP) is more fairly safe and it rapidly reduces the symptoms of anxiety through the control of the central nervous system (CNS) excitability by a selective and potent enhancement of inhibitory gammaamino butyric acid (GABA) mediated neurotransmission. Accelerated photochemical stability of alprazolam was performed under several conditions. The study involved the evaluation of the photostability of Alprazolam in active mater, in PVC/Aluminum blister packet (BPT) or without blister packet tablets (WBPT). The evaluation of the stability was performed using special stability test chambers at 60% controlled humidity, temperature and UV irradiation. The High-Performance Liquid Chromatography (HPLC) was used to analyze the content of the Alprazolam before and after UV irradiation. The obtained results for the short term photostability study do not show any significant degradation of this molecule by the UV irradiation in active mater and this holds true for the BPT or WBPT, independent of the Alprazolam content (0.25 or 0.50 mg).