HPLC of macromolecules

HPLC of macromolecules

VIII trends m analytrcal chemistry, vol 9, no 5,199O . boratory, assuming that use 1s made therein of MS and some form of chromatography Unfortunat...

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VIII

trends m analytrcal chemistry, vol 9, no 5,199O

.

boratory, assuming that use 1s made therein of MS and some form of chromatography Unfortunately, perhaps because of the author’s own research mterests and academic background, he has omrtted artifacts that might arise durmg atomic absorptron or emrssron spectroscopy, neutron activation analysis, electrophoresis, light scattering spectroscopy, IR/Raman spectroscopy, and so forth Thus many types of analytrcal methods wherem artifacts wrll also arise have not been included m the text, but this could also have been due to the sheer volume of mformatron that would have resulted The book relates, for example, how plastrcrzers from plastrc bottles or labware may contaminate analytical samples during work-up, preparation or actual analysis. It describes how mrstakes can be made in an analytrcal approach/method, what impurities may be present m commercial chemicals and solvents, what side-reactions could occur during a sample clean-up or derivatrzatron step, and similar problems leading to contamination, or the artrfactual formation or destruction of the analyte of interest The book 1s broken down into hundreds of separate sections, covering virtually all of the organic chemicals that might appear as artifacts during some type of analysis Other sections also cover molecular sieve artifacts, mineral oil contaminants, artifacts formed (positive or negative) during mtrosamme analysis, problems in sample collection and storage, rubber glove contaminants, TLC artifacts, and so forth In other words, it not only categorizes the most common organic contaminants or artifacts, but it also covers methods, materials, equipment and supplies that could add such materials to the final analysis or remove the analyte of interest from the final determmatron The chemical name of each compound is provided together wrth the molecular formula and molecular weight. This 1s followed by an actual mass spectrum under electron-impact iomzatron, the chemical structure, chemical abstracts servrce mdexing mformation (CAS name and registry number), Merck Index reference (Tenth Edition), synonyms (other common/trrvral names), and some text de-

scribing where the compound may occur as a contaminant, how it may be determined m various matrices, how artrfactual formation or disappearance of the compound can occur, and methods to prevent the artifacts of maJor concern m analysis Some of the more common reactions that the compound undergoes are described, whether the compound 1s used as a stabrliser for other chemicals or solvents, and the most common derivatives frequently encountered Addrtronal spectra, usually MS, are provided for the most common derivatives of the compound of interest. These may be formed mcrdentally d the sample of interest is treated wrth the corresponding reagents and derivatives of the contaminant would thus appear as artifacts. Cross-referencing is excellent where the compound may occur m other chemicals, where it may be converted vra derrvatization to other compounds, where rt may react with other chemicals, etc. For each compound there are references, mass spectra, chromatographrc methods of analysis, information on avoidance of artifacts, its role as a contaminant in other chemicals, what other chemicals may be present, and so forth Finally, mass spectra are hsted wrth sections devoted

to molecular ion, base peak, second peak, and third peak There are also major molecular formula, author, and subject indices, the latter being mcredibly lengthy and comprehensive, to aid the location of a particular monograph of mterest. Clearly, this 1sa very useful and practrcal book, but in vrew of rts size and the amount of mformatron contained also very expensive It should be m any hbrary that serves analytical chemists or services Thus, any academic, mdustrial or government laboratory that deals wrth analytical chemistry, analytical brochemrstry, analytical brotechnology, and related areas of chemistry, would benefit from having the book on site, d not down the hall m the nearest library faahty The author deserves a prize for what he has been able to compile, rt 1s an incredible amount of very practical, useful and applicable mformatron and advrce I. s. KRULL Professor I S IGull IS at the Department of Chemutry, The Bamett Instuute 341 MU; Northeastern Unwersrty,360 Huntmgton Avenue, Boston, MA, 02115, US.44

HPLC of macromolecules HPLC of Macromolecules. A Practtcal Approach, edited by R. W A Oliver; Oxford UmversttyPress, 1989 (v + 236 pages), f 1800, ISBN t&19-963021-6 (paperback), f27 00, ISBN 0-19963020-8 (sptralbound)

HPLC of macromolecules, particularly proteins and nucleic acids, is a field which has undergone exponential advances since the initial pubhcatrons on the technique m the mrd 1970’s There is therefore undoubtedly a need for a concise and practical text to help workers m this field Unfortunately this book does not reach the goals rt aspires to attain Whilst the companion volume HPLC of Small Molecules A Practical Approach, edited by Chan Kee Lrm, 1s

a valuable addition to the laboratory

reference collection, the same cannot be said of the present text The quality of the mformatron m this poorly edited multi-author collectron 1s variable, in many cases repetitive (for example Table 4 m Chapter 1 and Table 1 m Chapter 5) and m other cases suspect and contradrctory Thus m the preface the editor points out that srgm&ant losses of protem may occur on reversed-phase columns, whilst D Johns in Chapter 1 claims that the mass recovery of proteins and peptrdes IS generally good on reversed-phase P Corran m Chapter 5, which m my mmd is an example of how this book should have been written, being accurate and mformatrve with a number of practical hints and recipes, gets the problems of recovery mto perspective Another example of inconsistency is in Chapter

IX

trendsm analyhcalchemistry, vol 9, no $1990 .

2 where R. W. A. Oliver goes extensively and laboriously into comparisons between instrumentation for the HPLC for the separation of small molecules versus macromolecules whilst P Corran m Chapter 5 states that the apparatus needed for the RP-HPLC of proteins need not differ from that used with smaller molecules. Lastly there is also a &spar@ between chapters viz a vrz current content, several chapters bemg both out of date and lacking key references. In conclusions, whilst it would have been useful to have a reference manual for the HPLC of macromolecules, I feel that this book cannot be recommended.

E.C. NICE Dr E.C. Nice as at the Melbourne Titmow BiologyBranch, Ludwtg Inshtute for Cancer Research, RO. Royal Melbourne Hospital, Melbourne, Victorta 3050, Australia

Making light work....

Chemtlumtnescence and Photochemtcal Reaction Detectton in Chromatograph3 edtted by J W B&s, VCH Publrshers, 1989, f49.45 and DM 138 (291 pages), ISBN. O-89573-281-5VCH Publishers and ISBN: 3-527-26782-4 VCH Verlagsgesellschaft The combination of chemiluminescence (CL) and photochemical reactrons in one book seems strange, because, as the editor states in the preface, the processes are opposite. In the former, chemical reactions produce light and in the latter, light is absorbed by molecules to cause chemical reactrons to take place. However, they do have Important common (theoretical) aspects Moreover, both phenomena can be successfully applied in chromatography as reaction detection systems and can even be combined in one system (Chapter 7) The use of CL and photochemical reactions m analytrcal chemistry and especially in chromatography, as 1s stressed in this book, offers many possibdities

The introductory chapter (Birks) gives an overview of photophysical and photochemical principles. For many analytical chemists, this chapter contains many new subjects and will not be easily readable. However, the fundamental aspects treated in this chapter are missing in many books on analytical techniques and form a good basis for the rest of the book. Chapters 2 (Turnipseed and Birks) and 3 (Shearer and Sievers) have been devoted to CL detection in gas chromatography (GC). The flame CL on which the flame photometrrc detector is based, has been omitted because this can be found in many books on GC (detectors). Various reactions of highly reactive species (generated in different ways) and the analytes eluted from the column are presented Active nitrogen can be used for universal detection of hydrocarbons (formation of cyanogen radicals) and selective detection of drfferent elements. Ozone 1svery suitable for detection of, e.g., olefins. Other reactive species used for GC detection are fluor molecules (sulphur detection), fluor atoms, chlorine dioxide and sodmm atoms. Chapter 3 discusses (commercially available) detectors based on the reaction of NO and 03. Nitric oxide is generated post-column from the analytes and mixed wrth ozone. The thermal energy analyzer for detection of N-nitroso compounds which undergo catalyzed pyrolysis to form nitric oxide, is the most wellknown CL detection system in GC. In the nitrogen selective detector, oxygen is added to the column effluent so that nitrogencontaining compounds can be oxidized to nitric oxide. The redox CL detector utilizes the reaction of nitrogen dioxide or nitric acid and analytes producing nitric oxide Many chromatograms of real samples are shown and detection limits m the ppb and even ppt range can often be obtamed Chapter 4 (Nieman) is concerned wrth CL detection systems for liquid chromatography (LC). The CL reactions considered are lummol, lucigenin, peroxyoxalate and trrs(2,2’-bipyridine)ruthenium(II). Moreover, also the possrbilities of electrochemilummescence and lucrferm/lucrferase biolummescence are shown. Many interesting subjects are

drscussed and illustrated, eg. the detection of metal ions catalyzing the luminol reaction and also the detection of ligands of metal ions, the use of nnmobrlized reagents and the analytical potential of quenched CL. A negative point of this chapter is that only chormatograms are shown for luminolbased systems. Chapter 5 (Givens and Schowen) is an mdepth more theoretical treatment of the peroxyoxalate reaction. This reaction can be applied for the very sensitive detection of fluorophors and hydrogen peroxide and many recent papers are dealing with the use of this reaction for LC detection. The mechanism and kinetics of the reaction are drscussed Special attention has been paid to the fraction of the emrssion light that is measured (shown by an illustrative figure on the front of the book!) and how this 1s influenced by many parameters. Chapter 6 (Poulsen and Birks) is an extensive overview of photochemical reaction detection in HPLC. Perhaps the general introductron on reaction detection m this chapter is superfluous because this 1s also described m many books and review papers. The hardware for photochemical reaction detection and many applications of different types of photochemical reactions are clearly presented. Also the section ‘Conclusions and future drrections’ is very worthwhile The final chapter (Shellum and Birks) demonstrates the possibilities of reaction detection photochemtcal based on singlet oxygen sensrtrzatron The principle is that excited analytes produce singlet oxygen and, subsequently, detection takes place by means of a singletoxygen acceptor. Other possibilities of such a system are detection of the acceptor itself and detection of singlet oxygen quenchers UV absorption, fluorescence, CL, electrochemrstry and even mass spectrometry and photoiomzatron (in GC) are or seem possrble as detection methods The singlet oxygen sensrtrzation offers interesting posstbrlities but only two applications in LC are shown. In conclusion this book 1s not only worthwhrle for chromatographers mterested m new promrsmg detection modes but also for other analytical chemists working in the field of lumr-