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Anal Bioanal Chem ; 405(1): 351-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23092966


A substantial portion of the atmospheric particle budget is of biological origin (human and animal dander, plant and insect debris, etc.). These bioaerosols can be considered information-rich packets of biochemical data specific to the organism of origin. In this study, bioaerosol samples from various indoor environments were analyzed to create identifiable patterns attributable to a source level of occupation. Air samples were collected from environments representative of human high-traffic- and low-traffic indoor spaces along with direct human skin sampling. In all settings, total suspended particulate matter was collected and the total aerosol protein concentration ranged from 0.03 to 1.2 µg/m(3). High performance liquid chromatography was chosen as a standard analysis technique for the examination of aqueous aerosol extracts to distinguish signatures of occupation compared to environmental background. The results of this study suggest that bioaerosol "fingerprinting" is possible with the two test environments being distinguishable at a 97% confidence interval.

Aerossóis/química , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Cromatografia Líquida de Alta Pressão/métodos , Monitoramento Ambiental/métodos , Desenho de Equipamento , Humanos , Tamanho da Partícula , Material Particulado/análise , Proteínas/análise , Pele/patologia , Fatores de Tempo
Anal Bioanal Chem ; 403(1): 15-26, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22311424


The purpose of this review is to investigate the feasibility of bioaerosol fingerprinting based on current understanding of cellular debris (with emphasis on human-emitted particulates) in aerosols and arguments regarding sampling, sensitivity, separations, and detection schemes. Target aerosol particles include cellular material and proteins emitted by humans, animals, and plants and can be regarded as information-rich packets that carry biochemical information specific to the living organisms present where the sample is collected. In this work we discuss sampling and analysis techniques that can be integrated with molecular (e.g. protein)-detection procedures to properly assess the aerosolized cellular material of interest. Developing a detailed understanding of bioaerosol molecular profiles in different environments suggests exciting possibilities of bioaerosol analysis with applications ranging from military defense to medical diagnosis and wildlife identification.

Aerossóis , Estudos de Viabilidade , Humanos
Methods Enzymol ; 464: 327-42, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19903562


Bionanotubules are lipid-bound cylindrical structures with typical diameters in the tens of nanometers and length than can span up to hundreds of micrometers. Besides being observed in nature, bionanotubules can be prepared synthetically by various methods, some of which involve the extension of these structures from lipid vesicles. We describe the formation of lipid nanotubules from liposomes prepared with various lipid mixtures including phosphatidylcholine, phosphatidic acid, and various fluorescent phospholipids. We depict the methods used to extend bionanotubules from surface-attached vesicles, using electric fields as the driving force for bilayer extension and tubular growth. These methods include liposome preparation, surface attachment, and tubular extension by applying modest electric fields (<30V/cm). Methods in which lipid tubules are extended from liposomes that are free in solution and subject to higher magnitude fields are also described. In addition, we summarize other protocols of bionanotubule formation from liposomes, including various modes of micromechanical manipulation of lipid vesicles.

Biomimética , Lipossomos/química , Nanotubos/química , Tensoativos/química , Cromatografia Líquida de Alta Pressão , Microscopia Eletrônica de Varredura , Nanotecnologia/métodos
Langmuir ; 25(1): 391-6, 2009 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-19063629


Spontaneous formation of long-range (millimeters) membrane-bound nanotubules from surface-immobilized liposomes is possible by application of modest electric fields (2 -20 V/cm), providing a novel fabrication strategy for these hollow cylindrical structures. Stable tubes generally aligned with the applied electric field were created from liposomes prepared with phosphatidylcholine (PC), phosphatidic acid (PA), phosphoethanolamine (PE), and cholesterol. The minimum voltage which causes nanotubular formation (the onset voltage) and the average number of tubules per liposome of varying composition was examined with fluorescent microscopy using labeled phospholipids. Generally, the onset voltages ranged between 4 and 15 V/cm and depended on the mother vesicle composition. The results of this study suggest that increasing the charged lipid content can decrease the onset voltage. Conversely, a cholesterol content of more than 30% (by mass) was found to hinder extension of lipid tubules. Basic calculations that assume lipid migration and domain formation on the mother liposome as a nucleating site for tubule extension are assessed and suggest this is a reasonable model to describe the mechanism of tubular growth from immobilized liposomes.

Eletricidade , Lipossomos , Nanotubos , Colesterol/química , Microscopia de Fluorescência , Fosfolipídeos/química