Paper spray

Short oil alkyd resins can also be combined with nitrocellulose. They are readily soluble in typical nitrocellulose solvents (esters and ketones). Special short oil alkyd resins that are soluble in lower alcohols are often processed into furniture lacquers and acid-curing paints, and are also used in paper (spray) coatings and in flexoprint-... 

Aphis craccivora m.p. Pea, foliar spray Myzus persicae m.p. Pea, into water Diabrotica balteata L2 Filter paper, spray... 

Sukumar, H. Stone, J.A. Nishiyama, T. Yuan, C. Eiceman, G.A., Paper spray ionization with ion mobility spectrometry at ambient pressure, Int. J. Ion Mobil. Spectrom. 2011, 14,51-59. 

References H. Wang, J. Liu, R. G. Cooks, and Z. Ouyang, Paper spray for direct analysis of complex mixtures using mass spectrometry, Angew. Chem. (Int. 

Ed. Engl.) 49 877-880, (2010). N. E. Manicke, P. Abu-Rabie, N. Spooner, Z. Ouyang, and R. G. Cooks, Quantitative analysis of therapeutic drugs in dried blood spot samples by paper spray mass spectrometry An avenue to therapeutic drug monitoring, J. Am. Soc. Mass Spectrom. 22 1501-1507, (2011). 

Methods Ambient ionization methods, of which there are now over 20, e.g., desorption electrospray ionization (DESI), desorption atmospheric pressure chemical ionization (DAPC), desorption atmospheric pressme photo-ionization (DAPPI), and direct analysis in real time (DART), are now joined by paper spray, a method where ESI is initiated at the pointed tip of a piece of filter paper. A drop of blood ( 15 pi) is dried on the paper, and then the paper is moistened with 25 pi of a solvent suited to both the extraction of the analytes from the blood and the ESI process (e.g., 90% methanol 10% water with either 100 ppm acetic acid or 200 ppm sodium acetate). When the paper is exposed to high voltage (3-5 kV) while held close ( 5 mm) to the entrance of the mass analyzer, a spray (similar to electrospray) is induced at the tip of the paper as capillary action carries extracted compounds through the paper (Figure 4.5). The spray is maintained for 30-90 s at a flow rate comparable to that used in nano-electrospray. 

In another application, paper used to wipe a surface contaminated with heroin and cocaine was cut to provide the necessary emission point both drugs were detected. Paper spray was also shown to ionize various other compounds effectively, including methyl violet (a dye), phosphatidylcholine (a lipid), angiotensin (a peptide), and the protein cytochrome C. 

Paper spray methodology requires no modification of the mass spectrometer. The technique is carried out most effectively on MS/MS instruments (a triple quadrupole was used in these papers) as MS spectra tend to include many miscellaneous co-extracted compounds. CID with detection of the product ion spectra or operation in SRM mode enables both identification and quantification of the analytes. Paper spray is most effective in positive ion mode, although it is possible to use negative mode if the ESI voltage and solvent composition are altered to prevent a discharge. 

Paper spray is a novel method for assessing therapeutic concentrations for many drugs and could be applied in clinical settings. With appropriate hardware and software, the technique could be automated, providing rapid, inexpensive drug screening/assays that could be carried out by personnel without training in mass spectrometry. 

Detection Limits and Reproducibility Data for Drugs Analyzed in Dried Blood Spots Using Paper Spray... 

Sample on filter paper sprayed with the reagents... 

Liu, W., Wang, N., Lin, X., Ma, Y., Lin, J.-M. (2014) Interfacing Microsampling Droplets and Mass Spectrometry by Paper Spray Ionization for Online Chemical Monitoring of Cell Culture. Anal. Chem. 86 7128-7134. 

Salentijn, G.I.J., Permentier, H.P, Verpoorte, E. (2014) 3D-Printed Paper Spray Ionization Cartridge with Fast Wetting and Continuous Solvent Supply Features. Anal. Chem. 86 11657-11665. 

By combining microdialysis with nanoESI-MS, low-volume, low-concentration releases of small proteins in a three-dimensional neural cell culture system could be detected [78]. While microdialysis removes interferents, it also has an effect on the temporal resolution of the device ( 1 min). Alternatively, a microdialysis probe can be coupled with paper-spray ionization MS which enables the monitoring of glucose in a cell culture medium [79]. 

Han F., Yang Y., Ouyang J., and Na N. 2015. Direct analysis of in-gel proteins by carbon nanotubes-modified paper spray ambient mass spectrometry. Analyst, 140 710-715. 

Hamid AM, Jarmusch AK, Pirro V, Pincus DH, Clay BG, Gervasi G, Cooks RG. Rapid discrimination of bacteria by paper spray mass spectrometry. Anal Chem. 2014 86 7500-7. 

H. Ogihara, J. Xie, J. Okagaki, and T. Saji, Simple method for preparing superhydrophobic paper Spray-deposited hydrophobic silica nanoparticle coatings exhibit high water-repellency and transparency, Langmuir 28,4605-4608 (2012). 

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