The analytical Chemistry Lab


LogoLab_Pic.pngUnit Description

Our laboratory is an analytical unit, which provides Elemental Analysis and LCMS Analysis service for universities, chemical and pharmaceutical companies, research and industrial foundations. We perform the following evaluations:  analysis of C, H, N and O, the halogens: Cl,Br,I,F  and S,P, all in a broad spectrum of samples, (for example, synthesized organic compounds, natural products, coal and coal derived materials, pharmaceutical, industrial samples and others), High resolution mass determination, detection and separation in a wide range of polar masses such as: small molecules, proteins, peptides and oligonucleotides


Methods and Equipment


Elemental analysis


1.    Determination of C, H, N and O is performed using the Thermo Flash 2000 CHN-O Elemental Analyzer. It uses a simultaneous flash combustion method (950-10600C) for CHN and pyrolysis of oxygen to convert the sample elements to simple gases. The system uses a steady-state, wave front chromatographic approach to separate the controlled gases. They are detected as a function of their thermal conductivity. The analyzer uses a globally-recognized technique that is endorsed by official organizations worldwide. High speed microprocessor control, solid-state components and built-in diagnostics, provide assurance of performance fast, reliable, and accurate results for carbon, hydrogen, nitrogen, and oxygen detection.



CHN-O Elemental Analyzer


2.    Determination of halogens is done using the oxygen-flask combustion method (Schoniger application) or using the Anton Paar Microwave Induced Oxigen Combustion (MIC) for the decomposition of organic samples and subsequent potentiometric titration by the 835 Titrando Metrohm  Titroprocessor and by Ion chromatography analysis  using a Dionex IC system.


3.    Determination of sulfur is done via oxygen-flask combustion method or using the Anton Paar Microwave Induced Oxigen Combustion (MIC) for the decomposition of organic samples and subsequent gravimetric titration and by Ion chromatography analysis using a Dionex IC system.



4.      Determination of phosphorus is done using wet decomposition of organic samples followed by spectrophotometric detection or via oxygen-flask combustion method or using the Anton Paar Microwave Induced Oxigen Combustion (MIC) for the decomposition of organic samples and subsequent by Ion chromatography analysis using a Dionex IC system.


Oxygen-Flask Combustion

MIC Multiwave-PRO-03.jpg



835 Titrando IMG_1635 



Ion Chromatography IMG_1634


5.    Water Determination by Karl Fischer is done using 835 Titrando System consisting of a volumetric Karl Fischer titrator with built-in buret drive for volumetric Karl Fischer titrations.


Karl Fischer IMG_1637




CHN weight percentages are accurate and reproducible to within ± 0.3%, for a very pure sample. Halogens, S and P weight percentage are accurate and reproducible to within ± 0.5%.

Microbalance microbalance.JPG

Accurate weighing of samples is a prerequisite for organic elemental analysis since results are presented on a weight percent basis. A microbalance is an instrument capable of making precise measurements of weight of objects of relatively small mass: of the order of a million parts of a gram.


Mass spectrometry


6.    High Resolution Mass determination, separation and Qualitative and Quantitative MS analysis by LC(UV)MS/MS Analysis using Agilent 6520 QTOF analyzer. High-resolution LCMS/MS Quadruple Time Of Flight is an compound identification tool which allows distinguishing peaks separated by only small m/z values and provides excellent mass accuracy < 2ppm for MS and < 4 ppm for MS/MS also allows selective detection of desired compounds in the presence of interferences. Liquid Chromatography Mass Spectrometry enables chromatographic separation, identification and quantification of compounds in a wide range of masses. Ionization of the samples occurs in Dual Electro Spray Ionization source which is suitable for compounds that can have a charge induced and for multiply charged compounds such as: proteins, peptides, oligonucleotides. The samples for this analyzer have to be soluble in polar well vaporizable solvents.


Q-TOF LC/MS Agilent 6530 Q-TOF_Jet Stream_Front_Flat_Cropped_White Background_Medium Res


Sample submission:

*      You need to submit your sample in a small vial that is clearly labeled with a sample code and complete an "Elemental Analysis Request Form" or (and) the “MS Request Form"

*      Your sample code should consist of your initials and a number that refers to an individual sample. You can acquire blank forms from our lab, by post, or on-line Elemental Analysis form and MS form. Also, please complete and forward the payment form attached here.


Please provide as much information as possible about your sample, and what element you wish to determine. Give the formula and draw the structure or at least an indication. Deduce your %CHN, O, S, F, Cl, Br, I, and P content. It is essential that you provide your name, phone number, e-mail address, your advisor's or company name, and purchase order or account number for billing purposes.

You should provide a bare minimum of 5 milligrams for CHN analysis. You will need to provide an additional amount if you require further analysis in addition to CHN. In cases where you have a very small amount of sample, it is possible to do one CHN run with only 1 mg.

Analysis duration:

CHN and MS results are normally completed within 3 working days, but this can vary depending upon sample load and instrument problems.

Halogens, S and P analysis are usually finished within 5 working days.

You can ask for urgent analysis, at an additional cost.


Results can be picked up at the laboratory or sent to you via e-mail or regular mail.


For further information please contact the lab team:

Lab E-mail: micro.chem@mail.huji.ac.il

Lab manager: Dr. Carina Hazan E-mail: carinah@savion.huji.ac.il

Dr. Ella Jakob E-mail: ella.jakob@mail.huji.ac.il

Rachel Benzicry E-mail: rachelbe@savion.huji.ac.il


Tel: (972) 2-6585606

Fax: (972) 2-6584934





The analytical Chemistry Lab, The Hebrew University of Jerusalem

Edmond J. Safra Campus

Los Angeles building, room 114
Givat Ram, Jerusalem, 91904,Israel