RESUMO
Until now, there have been no relatively easy methods to measure the mass and mass distributions of nanoparticles/viruses. In this work, we report the first set of measurements of mass and mass distributions for nanoparticles/viruses using a novel mass spectrometry technology. In the past, mass spectrometry was typically used to measure the mass of a particle or molecule with a mass less than 1,000,000 Da. We developed cell mass spectrometry that can measure the mass of a cell or a microparticle. Nevertheless, there is a gap for mass measurement methods in the mass region of a nanoparticle or virus (1 MDa to 1 GDa). Here, we developed a nanoparticle/virus mass spectrometry technique to make rapid and accurate mass and mass distribution measurements of nanoparticles/viruses. This technique should be valuable for the quality control of nanoparticle production and the identification of various viruses. In the future, this method can also serve to monitor drug delivery when nanoparticles are used as carriers. Furthermore, it may be possible to measure the degree of infection by measuring the number of viruses in specific cells or in plasma.
Assuntos
HIV/química , Espectrometria de Massas/métodos , Nanopartículas/análise , Nanotecnologia/métodos , Humanos , Espectrometria de Massas/instrumentação , Peso Molecular , Nanotecnologia/instrumentação , Tamanho da Partícula , Poliestirenos , Fatores de TempoAssuntos
Carcinoma Hepatocelular/patologia , Fluordesoxiglucose F18 , Neoplasias Gengivais/diagnóstico , Neoplasias Gengivais/secundário , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Gengivais/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios XRESUMO
An instrument to directly measure the charge carried by a cell or a microparticle as well as mass-to-charge ratio of the cell/microparticle was developed for rapid mass distribution measurement. A successful mass spectrum with a record high mass has been demonstrated. In this article, the details of the construction and operation of the charge monitoring cell mass spectrometer are reported. Examples are also given for demonstration and discussion.
Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Calibragem , Sobrevivência Celular , Células Cultivadas , Humanos , Íons/químicaRESUMO
Herein, we report an application of charge-detection quadrupole ion trap mass spectrometry to the measurement of total dry masses of mammalian and poultry erythrocytes evaporated/ionized by laser-induced acoustic desorption. The method is rapid and widely applicable. Eight different types of red blood cells (RBCs) have been successfully analyzed, including those of human, goat, cow, mouse, pig, and chicken. The measured mean masses (weights per corpuscle) range from 0.58 x 10(13) Da (9.6 pg) of goat RBCs to 2.80 x 10(13) Da (46.5 pg) of chicken RBCs. The total dry weights determined for human RBCs from a healthy male adult, a patient with iron-deficiency anemia, and a patient with thalassemia are 34.8, 28.8, and 20.6 pg, respectively. These weights, except that of thalassemia, are all approximately 10% higher than their corresponding mean corpuscular hemoglobin values determined by a commercial automated hematology analyzer. The mass distribution profiles of the cells are all near-Gaussian, with a standard deviation of 15% for the normal human RBCs. The deviation increases significantly to 20% for RBCs with thalassemia characteristics and 27% for RBCs with iron-deficiency anemia characteristics. All the observations are in accord with their corresponding mean corpuscular volume measurements, indicating an increase in anisocytosis (variation in RBC size) in the anemic samples. Our results suggest a broad and promising application of this new technology to high-speed mass analysis of RBCs and other biological whole cells as well.
Assuntos
Separação Celular/métodos , Eritrócitos , Espectrometria de Massas/métodos , Adulto , Anemia Ferropriva/sangue , Animais , Humanos , Masculino , Padrões de ReferênciaAssuntos
Lasers , Linfócitos/efeitos da radiação , Monócitos/efeitos da radiação , Poliestirenos/química , Poliestirenos/efeitos da radiação , Acústica , Adsorção , Linhagem Celular Tumoral , Humanos , Luz , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Tamanho da Partícula , Sensibilidade e EspecificidadeRESUMO
[reaction: see text] Direct oxidative addition of CHCl3 to the Mg-TiCl4 bimetallic species resulted in the generation of a highly nucleophilic and practically convenient chloromethylenetitanium complex, which efficiently effected condensation even with enolizable or inert carbonyl compounds, such as sterically congested ketones, to provide vinyl chloride compounds.
RESUMO
Aggregation phenomena of tannin with bovine serum albumin were investigated by light scattering techniques including photon correlation spectroscopy and Rayleigh scattering. Tannin and albumin formed particles with diameters less than 1 microm at neutral pH. As revealed by this study, light scattering methods are useful in investigating aggregation phenomena of biomolecules and in directly quantifying tannin content.