The internal energies of the emitted ions can be modulated in an electrospray source through different experimental conditions. However, the fragmentation pattern depends also on conditions that cannot be controlled by the operator, e.g. the geometry of the source or the mode of transfer of the ions. These differences make difficult the comparison of the electrospray mass spectra obtained with different mass spectrometers. A method for the calibration of the internal energies of ions produced by an electrospray source has been presented previously to study the influence of experimental conditions on the internal energies of the ions. The method permits the calibration of individual working conditions. In this work, new results were obtained with modified values of fragmentation energy taking into account the kinetic shift of the thermometer ions. The internal energy distributions are compared for different instruments with different geometries, and are measured under different accelerating and focusing conditions. # 1998 John Wiley & Sons, Ltd. Received 4 June 1998; Revised 18 September 1998; Accepted 19 September 1998 Electrospray mass spectrometry allows the study of a variety of ion types from weakly bound complexes 1,-4 to fragments resulting from cleavage of strong covalent bonds. 5,6 Generally, it is assumed that the internal energy of the emitted ions can be modulated through the accelerating voltage in the source. However, the fragmentation pattern depends also on conditions that cannot be easily controlled by the operator, e.g. the geometry of the source or the mode of transfer of the ions. These differences make difficult the comparison of the results obtained using different mass spectrometers.A method for the calibration of the internal energy of the ions produced by an electrospray ionization (ESI) source was presented previously, to permit study of the influence of the experimental conditions on the internal energy of the ions. 7,8 The influence of the collision conditions and the composition of the mobile phase on the internal energy distributions was presented. The method is based on the correlation between the survival yieldof the probe ions (benzyl-substituted benzylpyridinium salts) and known appearance energies. In this paper, the appearance energies were calculated by Rice-Rampsberger-Kasser-Marcus (RRKM) theory as a function of the time of flight of the ions after their activation. This statistical theory allows one to take into account the higher internal energy (appearance energy, E app ) necessary to fragment molecules at observable rates in comparison with the critical energy for reaction (E 0 ). This excess energy is the kinetic shift (E ks ):The derivative of the curve obtained by plotting the survival rate as a function of appearance energy becomes an internal energy distribution of ions formed in the ESI source at fixed experimental conditions. This technique is similar to that described before, 7,8 but E 0 as referred to previously 1,8 is changed here to E app . The method develo...

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The internal energy deposited in the ions in the source of a mass spectrometer governs their fragmentation and therefore the content of the spectra. When the ionization conditions are well defined and reproducible, e.g. in electron impact, the elaboration of databases benefits the use of the method. In electrospray, however, the source conditions are not strictly defined. The elaboration of spectra databases therefore requires a calibration of the internal energy of the ions that is valid for all types of spectrometers. A method for the calibration of the internal energy of ions in electrospray is presented, developed using the fragmentation reactions of a set of probe ions (benzylpyridinium salts) under various conditions (the voltage on the sampling cone, the nature of the collision gas, the composition of the mobile phase). The influence of the experimental conditions on the internal energy of the ions permits the calibration of individual working conditions. # 1998 John Wiley & Sons, Ltd. Received 18 November 1997; Revised 20 December 1997; Accepted 22 December 1997 Rapid Commun. Mass Spectrom. 12, 165-170 (1998 The internal energy of ions governs their fragmentation and therefore the content of the mass spectra. In electrospray ionization (ESI), a variety of ion types is observed, depending on experimental conditions. Intact weakly bound complexes can be observed 1,2,3,4 in addition to fragments resulting from the cleavage of strong covalent bonds.5,6 The internal energy of the emitted ions can in fact be modulated in the source through the voltage applied in the so-called desolvation region. This modulation, controlled by the operator, gives considerable flexibility to the method and allows both structural and quantitative analysis. The fragmentation pattern depends also on conditions that are not adjustable by the operator, e.g. the geometry of the source, the mode of transfer of the ions to the analyser or conditions imposed by the high-performance liquid chromatographic (HPLC) separation such as the composition of the liquid phase. This prevents the elaboration of ESI spectral databases. It is therefore important to set up an independent method to calibrate the internal energy of ions that are emitted by the electrospray source, and to use it to study the influence of the experimental conditions on the content of the spectra. In this work, probe ions (benzylsubstituted benzylpyridinium salts), of known fragmentation energy barriers, were used as thermometer ions. The method is based on the correlation between the survival yield of the molecular ion and the fragmentation energy barrier for fixed experimental conditions. This approach has already been used to calculate the internal energy distribution of ions emitted by other 'soft' ionization techniques such as liquid secondary ion mass spectrometry (LSIMS) and laser desorption. 7,8 The accessible range of internal energies lies in the range 1-3 eV. The energy distributions were measured for different experimental conditions, varying the nature of the li...

To simulate the multicollisional heating process taking place in the intermediate pressure region of an electrospray source, ion trajectory calculations have been performed by introducing in the SIMION program a subroutine for handling the collision dynamics. The simulated internal energy distributions are compared with already available experimental distributions obtained by the “survival ion yield” method (Collette, C.; Drahos, L.; De Pauw, E.; Vékey, K. Rapid Commun. Mass Spectrom. 1998, 12, 1673). The latter have been satisfactorily reproduced by using a statistical model for the energy redistribution between the ion and the target gas. This model takes into account both activation and deactivation processes occurring upon collision in the acceleration/fragmentation region. It accounts for the important role of the number of degrees of freedom of the target on the shape of the internal energy distribution.

Context:The National Institute of Excellence in Health and Social Services (INESSS), which functions as the Québec health technology assessment (HTA) agency, tested a new way to engage patients along with health-care professionals in the co-construction of recommendations regarding implantable cardioverter-defibrillator replacement.Objective: The objective of this article was to describe the process of co-construction of recommendations and to propose methods of building best practices for patient involvement (PI) in HTA.Design: Throughout the process, documents were collected and participant observations were made. Individual interviews were conducted with patients, health-care professionals and the INESSS scientific team, Results: Three committees were established: an expert patient committee to reflect on patient experience literature; an expert health professional committee to reflect on medical literature; and a co-construction committee through which both patients and health-care professionals contributed to develop the recommendations. The expert patients validated and contextualized a literature review produced by the scientific team. This allowed the scientists to consider aspects related to the patient experience and to integrate the feedback from patients into HTA recommendations.The most important factor contributing to a positive PI experience was the structured methodology for selecting patient participants, and a key factor that inhibited the process was a lack of training in PI on the part of the scientific team.