Ultrafast control of the LnF/LnO ratio from Ln(hfac).

The photo-induced dissociative ionization of lanthanide complexes Ln(hfac) (Ln = Pr, Er, Yb) is studied using ultrafast shaped laser pulses in a time-of-flight (TOF) mass spectrometry setup. Various fluorine and Ln-containing mass fragments were observed, which can be interpreted by the photo-fragmentation mechanistic pathway involving C-C bond rotation processes proposed previously. A set of experiments used pulse shaping guided by closed-loop feedback control to identify pulses that optimize the ratio of LnF/LnO.

A Fully Integrated Online Platform For Real Time Monitoring Of Multiple Product Quality Attributes In Biopharmaceutical Processes For Monoclonal Antibody Therapeutics.

In response to FDA's call for Quality by Design (QbD) in biopharmaceutical product development, the biopharmaceutical industry has been developing highly sensitive and specific technologies in the monitoring and controlling of product quality attributes for bioprocesses. We previously published the successful application of an off-line multi-attribute method (MAM) to monitor more than 20 critical quality attributes (CQA) with superior sensitivity for the upstream process. To further remove the hurdles of laborious process sampling and sample preparation associated with the offline method, we present here a fully integrated MAM based online platform for automated real time online process monitoring.

Ultrafast Photofragmentation of Ln(hfac) with a Proposed Mechanism for forming High Mass Fluorinated Products.

The photo-induced dissociative-ionization of lanthanide complexes Ln(hfac) (Ln = Pr, Er, Yb) is studied using intense ultrafast transform limited (TL) and linearly chirped laser pulses in a time-of-flight (TOF) mass spectrometry setup. Various fluorine and Ln-containing high-mass fragments were observed in this experiment, including the molecular parent ion, which have not been seen with previous studies relying on relatively long-duration laser pulses (i.e.

Photofragmentation of Gas-Phase Lanthanide Cyclopentadienyl Complexes: Experimental and Time-Dependent Excited-State Molecular Dynamics.

Unimolecular gas-phase laser-photodissociation reaction mechanisms of open-shell lanthanide cyclopentadienyl complexes, Ln(Cp) and Ln(TMCp), are analyzed from experimental and computational perspectives. The most probable pathways for the photoreactions are inferred from photoionization time-of-flight mass spectrometry (PI-TOF-MS), which provides the sequence of reaction intermediates and the distribution of final products. Time-dependent excited-state molecular dynamics (TDESMD) calculations provide insight into the electronic mechanisms for the individual steps of the laser-driven photoreactions for Ln(Cp).