buffer solution

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1. a homogeneous mixture of one or more substances (solutes) dispersed molecularly in a sufficient quantity of dissolving medium (solvent).
2. in pharmacology, a liquid preparation of one or more soluble chemical substances, which are usually dissolved in water. For names of specific solutions, see under the name.
3. the process of dissolving or disrupting.
4. a loosening or separation.

Preparation of Solutions. Formula for preparing solutions from a pure drug:

For example, to prepare 2000 mL of a 2 per cent solution from boric acid crystals, the proportion would be

Formula for preparing solutions from stock solutions:

For example, to prepare 1000 mL of a 2 per cent solution from a 4 per cent stock solution, the proportion would be
aqueous solution one in which water is used as the solvent.
BCG solution an aqueous suspension of bacille Calmette-Guérin for instillation into the bladder to activate the immune system in treatment of superficial bladder cancers. It reduces the risk of a subsequent bladder cancer developing, although the exact mechanism of action is unknown.
buffer solution one that resists appreciable change in its hydrogen ion concentration (pH) when acid or alkali is added to it.
colloid solution (colloidal solution) imprecise term for colloid (def. 3).
hyperbaric solution one having a greater specific gravity than a standard of reference.
hypertonic solution one having an osmotic pressure greater than that of a standard of reference.
hypobaric solution one having a specific gravity less than that of a standard of reference.
hypotonic solution one having an osmotic pressure less than that of a standard of reference.
isobaric solution a solution having the same specific gravity as a standard of reference.
isotonic solution one having an osmotic pressure the same as that of a standard of reference.
molar solution a solution in which each liter contains 1 mole of the dissolved substance; designated 1 M. The concentration of other solutions may be expressed in relation to that of molar solutions as tenth-molar (0.1 M), etc.
normal solution a solution in which each liter contains 1 equivalent weight of the dissolved substance; designated 1 N.
ophthalmic solution a sterile solution, free from foreign particles, for instillation into the eye.
saturated solution one in which the solvent has taken up all of the dissolved substance that it can hold in solution.
sclerosing solution one containing an irritant substance (sclerosing agent) that will cause obliteration of a space, as in sclerotherapy.
standard solution one that contains in each liter a definitely stated amount of reagent; usually expressed in terms of normality (equivalent weights of solute per liter of solution) or molarity (moles of solute per liter of solution).
supersaturated solution an unstable solution containing more of the solute than it can permanently hold.
volumetric solution one that contains a specific quantity of solvent per stated unit of volume.

buffer solution

A solution of a weak acid and its salt, e.g., carbonic acid, sodium bicarbonate, important in maintaining a constant pH, esp. of the blood.
See also: solution
References in periodicals archive ?
Aitken RL (1992) Relationships between extractable Al, selected soil properties, pH buffer capacity and lime requirement in some acidic Queensland soils.
The pH buffer curves were determined in different ways for the 2 sample sets.
The best, although not the least expensive, way to calibrate these instruments is with a calibration kit that consists of pouches containing 4.0, 7.0, and 10.0 pH buffer and a rinse solution.
The size of this signal decreased as the concentration of the pH buffer HEPES was increased, consistent with the hypothesis that the signal detected indeed reflected hydrogen ions.
The slope of the electrode is calculated by determining the mV change between two different pH buffers. By dividing the mV difference by the change in pH units, users can get the actual slope of the electrode.
The [V.sub.th] was measured as a function of pH, with pH buffer solutions using the Ag/AgCl reference electrode as the gate electrode.
and NIST pH buffer The 2700 series benchtop meters from Paul N.
Daily Skin Balance is lightly fragranced with a nongreasy, lightweight and fast-absorbing formula that contains provitamin [B.sub.5], glycerin and a pH buffer to moisturize all day long.
The pH buffer capacity of the soil from each cropping system was determined by curves of pH after addition of alkaline or acid solutions at known concentrations.
Tenders invited for Ph/conductivity bench top meter kit including meter, ph/atc electrode,conductivity probe, ph buffer and solution kit, 1413 micro siemen conductivity standard,attached electrode stand and holder, universal power adopter, printed quick start guide and literature cd and usb computer cable detail specification as per annexure
Advanced features include up to five-point calibration, autobuffer recognition for both USA and NIST pH buffer sets, datalogging and recall of 100 data sets, and selectable manual or automatic temperature.