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Means of depart of ionic color atlas and detect the choice of means
From;    Author:Stand originally

Analyst is treated measure ion a few duer general news, should know the matrix condition that treats the molecular structure that measures compound and property and sample above all, be like inorganic or organic ion, ionic charge is counted, it is acerbity alkaline still, kiss water or scanty water, whether to wait for exterior active compound. Waiting for the hydrophoby that measures ion and hydration can be to decide to choose why to plant the main factor of detached means. What hydration can lose high with hydrophoby is ionic, be like Cl- or K, had better use HPIC depart. Hydration can be low with the ion with strong hydrophoby, be like perchloric acid (ClO4- ) or 4 butyl ammonium, had better use the post of ion exchange depart with powerful hydrophily or MPIC depart. Certain hydrophoby also has apparent hydration can PKa value is in 1 with the 7 ion between, salt of the acid that be like second or third acerbity salt, had better use HPICE depart. Some are ionic, can exchange depart with anion already, usable also cation exchanges depart, be like amino acid, alkaloid and transfer the metal.
A variety of a lot of ion are usable detecting means. Determine for example transfer when the metal, can use conductance or pulse directly with odd column law ampere detector, reaction is derived after usable also column, make metallic ion and PAR or action of other color developing agent, reoccupy UV/VIS detects. Common law is: Ultraviolet to notting have or absorb it is thus clear that and the acid of strong dissociation and alkaline, had better use conductance detector; Have electrochemistry active and the ion of losing dissociation, had better use a detector; To ionic itself or the complexing that generate after the reaction after carrying column content is in ultraviolet and visible have the ion that absorb or can produce fluorescence and compound, had better use UV/VIS or fluorescent detector. If want settlement problem to a few kinds of plan can choose to place, those who analyse plan is affirmatory and main by the complex degree of the type of matrix, alternative, process and whether economy will decide. Express 1 with 2 summary the detached way that can choose to all sorts of type ion and detect means.
The development of filling of ionic chromatographic column promoted the rapid development that ionic color atlas uses, the development that analyses a method to a variety of ion offerred a variety of possibility. What should put forward particularly is the aqueous solution in PH 0-14 and 100% organic dissolvent (turn over color atlas of photograph of concentrated juice to use organic dissolvent) in stable hydrophily is efficient the commercialization of filling of high capacity column, the applied limits that makes ion exchange detached more expand. The common ion that exists with ionic configuration in aqueous solution, include inorganic and organic ion, the salt with weak acid (Na2CO3/NaHCO3, KOH, NaOH) or strong acid (acid of H2SO4, methylic sulphur, HNO3, HCl) for photograph of going from place to place, anion is exchanged or cation exchanges depart, conductance detects, already was mature method, the color atlas requirement that has maturity can consult. Of the Shui Kerong to close neutral organic " big " element (relatively common young member) , if wait for,measure compound to be weak acid, because weak acid is in alkali sex solution,meet exist with anion configuration, because this is chosen stronger alkaline for photograph of going from place to place, anion exchanges depart; If wait for,measure compound to be weak base, because be in solution of strong acid sex,meet exist with cation configuration, choose stronger acid to make appearance of going from place to place, cation exchanges depart; The hydrophoby that if wait for,measures ion is stronger, because make with the sorption between stationary phase retain time longer or the peak pulls end, can join right amount and organic dissolvent in photograph of going from place to place, abate and adsorptive, shorten form of peak of reservation time, improvement and alternative. The depart that closes matter to this apperception also can choose ion to depart to color atlas, but more complex ion is contained commonly in photograph of going from place to place to reagent. In addition, to weak reservation ion can choose high capacity column and fluid of weak drip washing to be withheld in order to increase, ionic to strong reservation criterion conversely. What exist with ionic configuration in aqueous solution is ionic, namely stronger acid or alkaline, should choose conductance to detect. Have right ultraviolet or visible light has absorb base after reaction is being derived after group or classics column (in IC before using post lesser, derive) generate have the compound that attracts light radical group, choose optical detector. Have oxidation or reductive reaction can produce below extra voltage base round compound, can choose dc ampere or pulse ampere detect. To a few complex sample, get more information to take shape, but will two plant or series connection of 3 kinds of detector is used.
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