Effects of the Water Content in the Sample Preparation for MALDI on the Mass Spectra

1998 ◽  
Vol 70 (21) ◽  
pp. 4527-4533 ◽  
Author(s):  
Iddys D. Figueroa ◽  
Omar Torres ◽  
David H. Russell
Keyword(s):  
Sample Preparation ◽  
Water Content ◽  
Mass Spectra

The effects of sample preparation, pyrolysis and pyrolyzate transfer conditions on pyrolysis mass spectra

1979 ◽  
Vol 1 (1) ◽  
pp. 39-52 ◽  
Author(s):  
W. Windig ◽  
P.G. Kistemaker ◽  
J. Haverkamp ◽  
H.L.C. Meuzelaar
Keyword(s):  
Sample Preparation ◽  
Mass Spectra

scholarly journals Influence of sample preparation process on basic properties of biofuels

Paliva ◽  
2021 ◽  
pp. 141-148
Author(s):  
Hana Lisá ◽  
Martin Lisý ◽  
Patrik Elbl ◽  
Marek Baláš ◽  
Tereza Zlevorová ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Water Content ◽  
Volatile Matter ◽  
Moisture Loss ◽  
Grinding Process ◽  
Preparation Process ◽  
Wood Biomass ◽  
Crambe Abyssinica ◽  
Adjustment Method ◽  
Combustion Processes

The characteristic properties of non-wood biomass used in combustion processes are monitored, such as water content, ash, volatile matter. Biomass is usually not homogenous and of suitable dimensions for these determinations. This is the reason for the necessary adjustment of samples for analysis. But modifying the samples may change their properties. In this publication, the influence of the grinding process in a rotor mill on the content of water, volatile matter and ash in non-wood biomass samples was studied. Samples of flax, Crambe abyssinica, amaranth and rye were analyzed. All analyses showed moisture loss from the sample during grinding and in the case of flax, the loss of volatile matter was observed. It means the rotor mill is suitable for sample preparation prior to analysis. But for oil plants it is necessary to choose another mill or adjustment method.

scholarly journals Biodiesel Hasil Transesterifikasi Minyak Biji Nyamplung (Calophyllum inophyllum) Dengan Metanol

2017 ◽  
Vol 4 (2) ◽  
pp. 394-401 ◽  
Author(s):  
Rustam Musta ◽  
Aceng Haetami ◽  
Mimi Salmawati
Keyword(s):  
Moisture Content ◽  
Sample Preparation ◽  
Phosphoric Acid ◽  
Water Content ◽  
Seed Oil ◽  
Quality Parameter ◽  
Calophyllum Inophyllum ◽  
Good Concentration ◽  
Biodiesel Quality ◽  
Parameter Test

Study of the transesterification of Calophyllum innophyllum seed oil from Kendari with methanol has been conducted. The purpose of the research to determine of the yield of ester produced in transesterification process with methanol, the viscosity of biodiesel produced, moisture content of biodiesel produced, density of biodiesel produced. The methods used in this study are sample preparation, transesterification process, biodiesel quality parameter test consisting of viscosity, moisture content and density. The results showed that good concentration of phosphoric acid was used to remove the gum is 85%, the yield of ester produced in the process of transesterification with methanol is 111,647%, parameter of biodiesel quality measured that viscosity = 0,315 mm2/ s not fulfill Indonesian National Standart (INS), water content is 0.02 meets the INS and the density = 0.8725 g / cm3 meets the INS standard

Effect of Water Content in Extraction Mixture on the Pressurized Liquid Extraction Efficiency—Stability of Quercetin 4′-Glucoside During Extraction from Onions

2016 ◽  
Vol 99 (3) ◽  
pp. 744-749 ◽  
Author(s):  
Dorota Wianowska ◽  
Andrzej L Dawidowicz
Keyword(s):  
Sample Preparation ◽  
Water Content ◽  
Matrix Effects ◽  
Degradation Process ◽  
Extraction Process ◽  
Liquid Extraction ◽  
Pressurized Liquid Extraction ◽  
Extraction Temperature ◽  
Plant Analysis ◽  
Pure Methanol

Abstract Pressurized liquid extraction (PLE) is considered as an effective and quick sample preparation method, especially in plant analysis. This quick extraction process favors the isolation of compounds for which long exposure time in high temperatures is undesirable. However, despite this advantage, the application of PLE for plant compounds extraction involves certain problems, such as instability of the compounds. The obtained data proved that even in short-lasting PLE, quercetin 4′-glucoside undergoing the hydrolytical degradation process produces the corresponding aglycon quercetin when water is a component of the applied extractant. The increase of water content in methanol–water extractant mixture heightens the transformation degree of quercetin 4′-glucoside into quercetin and increases its concentration in the PLE extracts. The degradation is accelerated by increased extraction temperature and time. In plant samples, the degradation of quercetin 4′-glucoside is much higher because of the plant matrix effects. The presented results explain why extraction of quercetin from plants by pure methanol is less efficient than by water containing alcohol solutions. More importantly, they prove that the application of water–alcohol extractant during sample preparation leads to the hydrolytical degradation of glycosides to aglycones, and, as a consequence, to false conclusions in plant analysis.

scholarly journals ANALISIS KANDUNGAN PATI DALAM BATANG TANAMAN AREN (Arenga pinnata)

2012 ◽  
Vol 12 (2) ◽  
pp. 89
Author(s):  
Jardewig E Manatar ◽  
Julius Pontoh ◽  
Max R.J Runtuwene
Keyword(s):  
Sample Preparation ◽  
Water Content ◽  
Starch Content ◽  
Female Flower ◽  
Standard Curve ◽  
Research Activities ◽  
Palm Sugar ◽  
Sugar Plant ◽  
The Relationship ◽  
Productivity Factors

ANALISIS KANDUNGAN PATI DALAM BATANG TANAMAN AREN (Arenga pinnata) ABSTRAK Penelitian dilakukan untuk menganalisis kandungan pati dalam batang tanaman aren (Arenga pinnata) dengan caramengetahui variabilitas kandungan pati pada pohon aren di beberapa lokasi yang berbeda di Tomohon dan hubungannya dengan beberapa faktor produktivitas tanaman. Penelitian yang dilaksanakan meliputi pengambilan sampel, pengukuran kadar air, preparasi sampel, pembuatan kurva standar, dan analisis pati.  Hasilnya menunjukkan adanya perbedaan kandungan pati pada berbagai posisi di pengaruhi oleh produktivitas dari masing-masing pohon aren dari beberapa lokasi yang berbeda di Tomohon. Kandungan pati yang tertinggi diperoleh sekitar 1 m di bawah bunga betina pertama pada Posisi 5  bervariasi dari 26-37 %. Kandungan pati diatas 35 % dijadikan indikasi tanaman akan menghasilkan nira yang baik. Kata kunci : A. pinnata, Kandungan Pat.   ANALYSIS OF STARCH CONTENT IN STALK PALM SUGAR PLANT (Arenga pinnata) ABSTRACT The research do to analyze starch content in stalk palm sugar plant (Arenga pinnata) with to know the variability of starch content in palm sugar plant at some different location in Tomohon and the relationship with some productivity factors of plant. The research activities included starch sampling, measurement of water content, sample preparation, making standard curve and analysis of starch content. The results showed different starch content at various position at a tree and in the trees at various locations in Tomohon.  The starch content corelated to the productivity of each palm sugar trees at different location in Tomohon. The highest of starch content found about one meter under first female flower at the fifth position has variation from 26-37%. Starch content above 35% indicated that tree will produce juice. Keywords : A. pinnata, Starch Content

scholarly journals CHARACTERIZATION OF NON-STEROIDAL ANTI-INFLAMMATORY DRUGS IN TABLETS BY DIRECT ANALYSIS IN REAL TIME/TIME OF FLIGHT/MASS SPECTROMETRY (DART/TOF/MS) WITHOUT SAMPLE PREPARATION

2020 ◽  
Vol 5 (12) ◽  
pp. 191-199
Author(s):  
Nawaf Masfer Saad Al-Otaibi
Keyword(s):  
Sample Preparation ◽  
Mass Spectra ◽  
Direct Analysis ◽  
Ion Source ◽  
The Other ◽  
Active Principle ◽  
Local Market ◽  
Molecular Ion ◽  
Inflammatory Drugs ◽  
Anti Inflammatory

This powerful mass spectrometric technique was used to investigate four profen drugs which are widely used as non-steroidal anti-inflammatory drugs for treating pain, fever and inflammation: Ibuprofen (M = 206), Flurbiprofen (M = 244), Naproxen (M = 230) and Ketoprofen (M = 254). The DART ion source was operated in positive ion mode with helium as the ionizing medium heated to 250°C. A solution containing a mixture of poly (ethylene glycol) standards PEG 600 and PEG 200 was used for mass calibration. A standard solution of each pure standard was manually introduced by using a small glass rod. The high resolution mass spectra of Ibuprofen, Flurbiprofen, Naproxen and Ketoprofen showed the presence of an intense protonated molecular ion [M + H]+ at 207.13860, 245.09776, 231.10632 and 255.09966 Da, respectively. Moreover, a non-protonated molecular ion M+ was also observed except for Ketoprofen. On the other hand, an intense adduct ion [M + H2O]+ was also present in the four mass spectra. Since these profens are 2-arylpropionic acid derivatives they have a known tendency to form dimers; indeed, an intense protonated ion corresponding to this dimer [2M + H]+ was present in the spectrum of Ibuprofen, Flurbiprofen, Naproxen and Ketoprofen at 413.27102, 489.19944, 461.19266 and 509.19662 Da, respectively. The presence of profens as active ingredients was then investigated in various pharmaceutical tablets collected from the local market. A small piece of each solid tablet was submitted to the DART ion source without any sample preparation. The obtained mass spectrum showed the characteristic peaks corresponding to each profen as active principle, as well as the other ingredients of the tablet.

DNA amplification in mixed aqueous-organic media: chemical analysis of leading polymerase chain reaction compositions

2021 ◽  
Author(s):  
Jalel Neffati ◽  
Ioanna Petrounia ◽  
Rudy D. Moreira ◽  
Raj Chakrabarti
Keyword(s):  
Sample Preparation ◽  
Mass Spectra ◽  
Matrix Effects ◽  
Pcr Amplification ◽  
Dna Amplification ◽  
Polymerase Activity ◽  
Ion Source ◽  
Amplification Efficiency ◽  
Internal Standards ◽  
Polymerase Chain

AbstractPCR amplification of GC-rich regions often leads to low yield and specificity. Addition of PCR-enhancing compounds is employed in order to overcome these obstacles. PCR-enhancing additives are low molecular polar organic compounds that are included as undisclosed co-solvents in commercial PCR buffers. In the interest of transparency and to permit further optimization by researchers of PCR compositions for challenging amplification problems, we studied eight PCR buffers by GC/MS to identify and quantify their co-solvents. Buffer specificity, both rich in water and salified substances, required a suitable sample preparation before injection into the GC/MS system. The aqueous phase of each buffer was replaced by an organic solvent to remove, by precipitation and filtration, salified substances which are detrimental to the GC/MS analysis. This approach has demonstrated the advantage of eliminating both water and salified substances without any loss of co-solvents. The sensitivity of the developed method was demonstrated as the main co-solvents were easily detected, identified and quantified. The methodology for identifying the co-solvents is mainly based on comparison of both library matching of acquired MS spectra with NIST library and experimental mass spectra obtained from authentic chemical standards. For the quantification of each co-solvent, deuterated Internal standards of similar structure to the cosolvents were used to correct the variable recovery caused by sample preparation, matrix effects, and ion source variability. The recovery ratio of the developed method was verified and found to be in the range 90-120 %. We then characterized the effects of specific organic co-solvents identified during PCR amplification -- using DNA melting, polymerase thermostability, polymerase activity and real-time PCR methods -- in order to elucidate their mechanism of action and to permit further optimization of their effects on amplification efficiency and specificity.

Determination of catechin and epicatechin in the peel of apple varieties resistant and non-resistant to apple scab

2010 ◽  
Vol 64 (6) ◽  
Author(s):  
Marek Gołębiowski ◽  
Edmund Maliński ◽  
Małgorzata Szankin ◽  
Mariusz Marszeniuk ◽  
Monika Paszkiewicz ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Solid Phase Extraction ◽  
Mass Spectra ◽  
Solid Phase ◽  
Apple Scab ◽  
Phase Extraction ◽  
Apple Trees ◽  
Apple Peel ◽  
Apple Cultivars

AbstractCatechin and epicatechin were analysed in the peel of six apple cultivars (three resistant and three non-resistant to apple scab). Two methods of analytical sample preparation following extraction were tested: solid phase extraction and column separation with Sephadex LH-20 coupled to a differential refractometric detector. Prior to GC and GC-MS analyses, these compounds were silylized. This permitted co-injection with standards and the comparison of retention values and mass spectra with those recorded for standards. The content of catechin and epicatechin in apple peel is discussed in relation to the resistance of apple trees to scab.

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