Amoxicillin Tablets
DEFINITION
Amoxicillin Tablets contain NLT 90.0% and NMT 120.0% of the labeled amount of amoxicillin (C16H19N3O5S).
IDENTIFICATION
A.
The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
ASSAY
• Procedure
Buffer:
6.8 g/L of monobasic potassium phosphate in water. Adjust with a 45% (w/w) solution of potassium hydroxide to a pH of 5.0 ± 0.1.
Mobile phase:
Acetonitrile and Buffer (1:24)
Standard solution:
1.2 mg/mL of USP Amoxicillin RS in Buffer. [Note—Use this solution within 6 h. ]
Sample solution:
Place NLT 5 Tablets in a high-speed glass blender jar containing Buffer sufficient to yield a concentration of 1 mg/mL of anhydrous amoxicillin. Blend for 4 ± 1 min, allow to stand for 5 min, and centrifuge a portion of the mixture. [Note—Where the volume of Buffer required would exceed 500 mL, place 5 Tablets in a volumetric flask of such capacity that when finally diluted to volume, a concentration of 1 mg of anhydrous amoxicillin per mL would be obtained. Add a volume of Buffer equivalent to three-fourths of the capacity of the volumetric flask, and sonicate for 5 min. Dilute with Buffer to volume, add a magnetic stirring bar, and stir for 30 min. Centrifuge a portion of this solution. ]
Pass a portion of the clear supernatant through a suitable filter. [Note—Use this solution within 6 h. ]
Chromatographic system
Mode:
LC
Detector:
UV 230 nm
Column:
4-mm × 25-cm;10-µm packing L1
Flow rate:
1.5 mL/min
Injection size:
10 µL
System suitability
Sample:
Standard solution
Suitability requirements
Tailing factor:
NMT 2.5
Relative standard deviation:
NMT 2.0%
Analysis
Samples:
Standard solution and Sample solution
Calculate the percentage of C16H19N3O5S in each Tablet taken:
Result = (rU/rS) × (CS/CU) × P × F × 100
| rU | = | = peak response of amoxicillin from the Sample solution |
| rS | = | = peak response of amoxicillin from the Standard solution |
| CS | = | = concentration of USP Amoxicillin RS in the Standard solution (mg/mL) |
| CU | = | = nominal concentration of amoxicillin in the Sample solution (mg/mL) |
| P | = | = potency of amoxicillin in USP Amoxicillin RS (µg/mg) |
| F | = | = conversion factor, 0.001 mg/µg |
Acceptance criteria:
90.0%–120.0%
PERFORMANCE TESTS
• Dissolution 
711
711
Medium:
Water; 900 mL
Apparatus 2:
75 rpm
Time:
30 min
Determine the amount of C16H19N3O5S dissolved by using the following method.
Buffer:
27.2 g of monobasic potassium phosphate in 3 L of water. Adjust with a 45% (w/w) solution of potassium hydroxide to a pH of 5.0 ± 0.1. Dilute with water to obtain 4 L of solution.
Mobile phase:
Acetonitrile and Buffer (1:39)
Standard solution:
0.05 mg/mL of USP Amoxicillin RS in Buffer. [Note—Use this solution within 6 h. ]
Sample solution:
Pass a portion of the sample through a suitable filter of 0.5-µm pore size. Quantitatively dilute a volume of the filtrate with water to obtain an estimated concentration of 0.045 mg/mL of amoxicillin. Use this solution within 6 h.
Chromatographic system
Mode:
LC
Detector:
UV 230 nm
Column
Analytical:
3.9-mm × 30-cm; packing L1
Guard:
2-mm × 2-cm; packing L2
Column temperature:
The analytical column is maintained at a constant temperature of 40 ± 1
.
.
Flow rate:
0.7 mL/min
Injection size:
10 µL
System suitability
Sample:
Standard solution
Suitability requirements
Capacity factor:
1.1–2.8
Column efficiency:
NLT 1700 theoretical plates
Tailing factor:
NMT 2.5
Relative standard deviation:
NMT 1.5%
Analysis
Samples:
Standard solution and Sample solution
Calculate the percentage of C16H19N3O5S dissolved:
Result = (rU/rS) × (CS/L) × (D/V) × P × F × 100
| rU | = | = peak response of amoxicillin from the Sample solution |
| rS | = | = peak response of amoxicillin from the Standard solution |
| CS | = | = concentration of USP Amoxicillin RS in the Standard solution (mg/mL) |
| L | = | = label claim (mg/Tablet) |
| D | = | = dilution factor for the Sample solution |
| V | = | = volume of the dissolution medium, 900 mL |
| P | = | = potency of amoxicillin in USP Amoxicillin RS (µg/mg) |
| F | = | = conversion factor, 0.001 mg/µg |
Tolerances:
NLT 75% (Q) of the labeled amount of C16H19N3O5S is dissolved.
For products labeled as chewable Tablets:
Proceed as directed above.
For chewable Tablets labeled to contain 200 or 400 mg
Time:
20 min
Tolerances:
NLT 70% (Q) of the labeled amount of C16H19N3O5S is dissolved.
For chewable Tablets labeled to contain 125 or 250 mg
Time:
90 min
Tolerances:
NLT 70% (Q) of the labeled amount of C16H19N3O5S is dissolved.
For veterinary products:
Proceed as directed above, except use Apparatus 2 at 100 rpm.
SPECIFIC TESTS
• Microbial Enumeration Tests 61 and Tests for Specified Microorganisms 62:
The total aerobic microbial count does not exceed 103 cfu/g, and the total combined molds and yeasts count does not exceed 102 cfu/g.
61 and Tests for Specified Microorganisms 62:
The total aerobic microbial count does not exceed 103 cfu/g, and the total combined molds and yeasts count does not exceed 102 cfu/g.
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in tight containers, and store at controlled room temperature.
• Labeling:
Label chewable Tablets to indicate that they are to be chewed before swallowing. Tablets intended solely for veterinary use are so labeled.
• USP Reference Standards 11
11
USP Amoxicillin RS
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Ahalya Wise, M.S.
Senior Scientific Liaison 1-301-816-8161 |
(SM12010) Monographs - Small Molecules 1 |
| 711 |
Margareth R.C. Marques, Ph.D.
Senior Scientific Liaison 1-301-816-8106 |
(GCDF2010) General Chapters - Dosage Forms |
| 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 1-301-816-8339 |
(GCM2010) General Chapters - Microbiology |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 2202
Pharmacopeial Forum: Volume No. 36(4) Page 896