Maltitol Solution
DEFINITION
Maltitol Solution is a water solution containing, on the anhydrous basis, NLT 50.0% of d-maltitol (C12H24O11) (w/w) and NMT 8.0% of d-sorbitol (C6H14O6) (w/w). The amounts of total sugars, other polyhydric alcohols, and any polyol anhydrides, if detected, are not included in the requirements nor in the calculated amount under Other Impurities.
IDENTIFICATION
•  A. Procedure
Sample:  1.4 g of Maltitol Solution
Analysis:  Dissolve the Sample in 75 mL of water. Transfer 3 mL of this solution to a 15-cm test tube, add 3 mL of freshly prepared catechol (1 in 10), and mix. Add 6 mL of sulfuric acid, and mix. Gently heat the tube in a flame for about 30 s.
Acceptance criteria:  A deep pink or wine-red color appears.
•  B. The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
•  C. Limit of Diethylene Glycol and Ethylene Glycol
Diluent:  Acetone and water (96:4)
Standard stock solution:  0.5 mg/mL of USP Diethylene Glycol RS and 0.5 mg/mL of USP Ethylene Glycol RS in Diluent
Internal standard stock solution:  0.5 mg/mL of 1,3-butanediol (internal standard) in Diluent
Standard solution:  0.04 mg/mL of USP Diethylene Glycol RS, 0.04 mg/mL of USP Ethylene Glycol RS, and 0.04 mg/mL of 1,3-butanediol, in Diluent, prepared from the Standard stock solution and Internal standard stock solution
Sample solution:  Transfer 1.0 g of Maltitol Solution to a 25-mL volumetric flask. Add 1.0 mL of water to the flask, and mix on a vortex mixer for 3 min. Add 2.0 mL of the Internal standard stock solution and 5 mL of Diluent, and mix on a vortex mixer for 3 min. Add the remaining Diluent to the flask to volume in two equal portions. Mix the contents for about 3 min after each addition of Diluent. Pass a portion of the supernatant layer through a nylon filter of 0.45-µm pore size. Discard the first 2 mL of the filtrate, and collect the rest of the filtrate for analysis. [Note—Acetone is used to precipitate maltitol. ]
Chromatographic system 
Mode:  GC
Detector:  Flame ionization
Column:  0.32-mm × 15-m fused-silica capillary column; 0.25-µm layer of phase G46
Temperature 
Detector:  300
Injection port:  240
Column:  See temperature program table below.
Initial
Temperature
()
Temperature
Ramp
(/min)
Final
Temperature
()
Hold Time
at Final
Temperature
(min)
70 70 2
70 50 300 5
Carrier gas:  Helium
Flow rate:  3.0 mL/min
Injection size:  1.0 µL
Injection type:  Split injection. The split ratio is about 10:1. [Note—A general purpose split/splitless, taper, glass wool, and deactivated liner is used. ]
System suitability 
Sample:  Standard solution
[Note—See the relative retention time table below. Relative retention times are provided for information only, and the standards should be used to ensure appropriate peak identification. ]
Name Relative
Retention
Time
Ethylene glycol 1.0
1,3-Butanediol (internal standard) 2.2
Diethylene glycol 2.8
Suitability requirements 
Resolution:  NLT 15 between ethylene glycol and 1,3-butanediol
Analysis 
Samples:  Standard solution and Sample solution
Based on the Standard solution, identify the peaks of ethylene glycol, 1,3-butanediol (internal standard), and diethylene glycol. Compare peak area ratios of ethylene glycol to the internal standard and of diethylene glycol to the internal standard in the Standard solution and Sample solution, respectively.
Acceptance criteria 
Diethylene glycol:  The peak area ratio of diethylene glycol to the internal standard in the Sample solution is NMT the peak area ratio of diethylene glycol to the internal standard in the Standard solution, corresponding to NMT 0.10% of diethylene glycol in Maltitol Solution.
Ethylene glycol:  The peak area ratio of ethylene glycol to the internal standard in the Sample solution is NMT the peak area ratio of ethylene glycol to the internal standard in the Standard solution, corresponding to NMT 0.10% of ethylene glycol in Maltitol Solution.
ASSAY
•  Procedure
Mobile phase:  Water
Standard solution:  10 mg/g of USP Maltitol RS and 1.6 mg/g of USP Sorbitol RS
Sample solution:  20 mg/g of Maltitol Solution in water
Chromatographic system 
Mode:  LC
Detector:  Refractive index
Column:  7.8-mm × 10-cm; packing L34
Temperature 
Column:  60 ± 2
Detector:  35
Flow rate:  0.5 mL/min
Injection size:  10 µL
System suitability 
Sample:  Standard solution
[Note—The relative retention times for maltotriitol, maltitol, and sorbitol are 0.38, 0.48, and 1.0, respectively. ]
Suitability requirements 
Tailing factor:  NMT 1.2 for maltitol and sorbitol
Relative standard deviation:  NMT 2.0%
Analysis 
Samples:  Standard solution and Sample solution
Calculate the percentage, on the anhydrous basis, of C12H24O11 and C6H14O6 in the portion taken:
Result = (rU/rS) × (CS/CU) × [100/(100 W)] × 100
rU== peak response of d-maltitol or d-sorbitol from the Sample solution
rS== peak response of d-maltitol or d-sorbitol from the Standard solution
CS== concentration of the appropriate USP Reference Standard in the Standard solution (mg/g)
CU== concentration of Maltitol Solution in the Sample solution (mg/g)
W== percentage in the test for Water Determination
Acceptance criteria:  NLT 50.0% of d-maltitol (w/w) and NMT 8.0% of d-sorbitol (w/w), on the anhydrous basis
IMPURITIES
Inorganic Impurities 
•  Residue on Ignition 281: NMT 0.1%, calculated on the anhydrous basis, determined on a 2-g portion
•  Limit of Nickel
Solution A:  10 mg/mL of ammonium pyrrolidine dithiocarbamate
Sample solution:  Dissolve and dilute 20.0 g of Maltitol Solution with diluted acetic acid to 100 mL. Add 2.0 mL of Solution A and 10.0 mL of methyl isobutyl ketone, and shake for 30 s. Protect from bright light. Allow the two layers to separate, and use the methyl isobutyl ketone layer.
Standard solutions:  Prepare as directed for the Sample solution, except to prepare three solutions by adding 0.5, 1.0, and 1.5 mL of nickel standard solution TS.
Blank solution:  Prepare as directed for the Sample solution, except to omit the use of the Maltitol Solution.
Spectrometric conditions 
Mode:  Atomic absorption spectrophotometry
Analytical wavelength:  232.0 nm (maximum absorbance)
Lamp:  Nickel hollow-cathode
Flame:  Air–acetylene
Analysis 
Samples:  Sample solution, Standard solutions, and Blank solution
Set the instrument to zero using the Blank solution. Concomitantly determine the absorbances of the Standard solutions and the Sample solution at least three times each. Record the average of the steady readings for each of the Standard solutions and the Sample solution. Between each measurement, aspirate the Blank solution, and ascertain that the reading returns to zero. Plot the absorbances of the Standard solutions and the Sample solution versus the added quantity of nickel. Extrapolate the line joining the points on the graph until it meets the concentration axis. The distance between this point and the intersection of the axes represents the concentration of nickel in the Sample solution.
Acceptance criteria:  NMT 1 ppm, calculated on the anhydrous basis
Organic Impurities 
•  Procedure: Reducing Sugars
Sample:  An amount of Maltitol Solution equivalent to 3.3 g on the anhydrous basis
Analysis:  To the Sample add 3 mL of water, 20.0 mL of cupric citrate TS, and a few glass beads. Heat so that boiling begins after 4 min, and maintain boiling for 3 min. Cool rapidly, and add 40 mL of diluted acetic acid, 60 mL of water, and 20.0 mL of 0.05 N iodine VS. With continuous shaking, add 25 mL of a mixture of 6 mL of hydrochloric acid and 94 mL of water. When the precipitate has dissolved, titrate the excess of iodine with 0.05 N sodium thiosulfate VS using 2 mL of starch TS, added toward the end of the titration, as an indicator.
[Note—The amount determined in this test is not included in the calculated amount under Other Impurities. ]
Acceptance criteria:  NLT 12.8 mL of 0.05 N sodium thiosulfate VS is required, corresponding to NMT 0.3% of reducing sugars, on the anhydrous basis, as glucose.
SPECIFIC TESTS
•  Microbial Enumeration Tests 61 and Tests for Specific Microorganisms 62: The total aerobic microbial count using the Plate Method is NMT 1000 cfu/mL, and the total combined molds and yeasts count is NMT 100 cfu/mL.
•  pH 791: 5.0–7.5, in a 14% (w/w) solution of Maltitol Solution in carbon dioxide-free water
ADDITIONAL REQUIREMENTS
•  Packaging and Storage: Preserve in well-closed containers. No storage requirements are specified.
•  USP Reference Standards 11
USP Diethylene Glycol RS Click to View Structure
USP Ethylene Glycol RS
USP Maltitol RS Click to View Structure
USP Sorbitol RS Click to View Structure
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1-301-816-8335
(EXC2010) Monographs - Excipients
61 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
1-301-816-8339
(GCM2010) General Chapters - Microbiology
62 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
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(GCM2010) General Chapters - Microbiology
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USP35–NF30 Page 1853
Pharmacopeial Forum: Volume No. 30(3) Page 984