A combined methodological approach supports a two-state reaction model including a 1 : 1 binding of anthracyclines and aptamers and a subsequent conformational change of the binding complex.

High oxygen permeable [poly(TMSP)] nanofibers incorporating porphyrin macrocycle as luminescence indicators were prepared by electrospinning technique. The porphyrins involves were modified by i) introducing phenylacetylide substituents on the para position of the phenyl moieties and ii) varying the metal centers [Pt(II) or Pd(II)] of the meso-tetrakisphenylporphyrins. A set of nanofibers; (Pt-TPP)NF, (Pd-TPP)NF, (Pt-TPA)NF and (Pd-TPA)NF were obtained to study their structure-activity relationship toward oxygen. The lifetime-based technique was privileged to take advantage of their long-lived phosphorescent properties. A two-fold enhancement was observed for (Pt-TPA)NF and (Pd-TPA)NF compared to (Pt-TPP)NF and (Pd-TPP)NF demonstrating the positive effect of the phenylacetylide moieties on the lifetime. Also, Silver nanoparticles were included in nanofibers to investigate their influence on lifetime-based oxygen sensitivity, showing that the presence of AgNPs only affects (Pd-TPA)NF.

The capability of electrospray ionization (ESI)‐ion mobility (IM) spectrometry for reaction monitoring is assessed both as a stand‐alone real‐time technique and in combination with HPLC. A three‐step chemical reaction, consisting of a Williamson ether synthesis followed by a hydrogenation and an N‐alkylation step, is chosen for demonstration. Intermediates and products are determined with a drift time to mass‐per‐charge correlation. Addition of an HPLC column to the setup increases the separation power and allows the determination of further species. Monitoring of the intensities of the various species over the reaction time allows the detection of the end of reaction, determination of the rate‐limiting step, observation of the system response in discontinuous processes, and optimization of the mass ratios of the starting materials. However, charge competition in ESI influences the quantitative detection of substances in the reaction mixture. Therefore, two different methods are investigated, which allow the quantification and investigation of reaction kinetics. The first method is based on the pre‐separation of the compounds on an HPLC column and their subsequent individual detection in the ESI‐IM spectrometer. The second method involves an extended calibration procedure, which considers charge competition effects and facilitates nearly real‐time quantification.

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The solution of a Mannich reaction was electrosprayed to study their conversion ratio at various ES parameter. Implementing new methods demonstrated low influence of the gas phase and a high effect of the life time and the charge of the μ-droplets.