Mode: LC

Detector: UV 254 nm

Column: 4.6-mm × 25-cm; 5-µm packing L1

Column temperature: 40

Flow rate: 1 mL/min

Injection volume: 20 µL

Run time: NLT 2 times the retention time of nicardipine

System suitability

Sample: Standard solution

Suitability requirements

Tailing factor: NMT 2.0

Relative standard deviation: NMT 2.0%

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of the labeled amount of nicardipine hydrochloride (C26H29N3O6·HCl) in the portion of Injection taken:

Result = (rU/rS) × (CS/CU) × 100

rU	=	= peak area of nicardipine from the Sample solution
rS	=	= peak area of nicardipine from the Standard solution
CS	=	= concentration of USP Nicardipine Hydrochloride RS in the Standard solution (mg/mL)
CU	=	= nominal concentration of nicardipine hydrochloride in the Sample solution (mg/mL)

Acceptance criteria: 90.0%–110.0%

IMPURITIES

• Limit of N-Benzyl-N-methyl-ethanolamine

Solution A: Dissolve 2.80 g of sodium perchlorate monohydrate in 1 L of water. Adjust with perchloric acid to a pH of 2.5.

Solution B: Acetonitrile and methanol (500:500)

Diluent: Acetonitrile and water (20:80)

Mobile phase: See Table 1.

Table 1

Time (min)	Solution A (%)	Solution B (%)
0	95	5
10	82	18
12	20	80
22	20	80
24	95	5
32	95	5

Standard solution: 2.5 µg/mL of USP N-Benzyl-N-methyl-ethanolamine RS in Diluent prepared as follows. To a suitable amount of USP N-Benzyl-N-methyl-ethanolamine RS, add Diluent to 70% of the final volume. Sonicate to dissolve. Cool, and dilute with Diluent to volume. Pass the solution through a suitable filter of 0.45-µm pore size.

Sample solution: Nominally equivalent to 0.5 mg/mL of nicardipine hydrochloride in Diluent from a suitable volume of Injection. Pass the solution through a suitable filter of 0.45-µm pore size.

Chromatographic system

Mode: LC

Detector: UV 205 nm

Column: 4.6-mm × 15-cm; 5-µm packing L1

Flow rate: 1.5 mL/min

Temperatures

Column: 30

Sample: 10

Injection volume: 50 µL

System suitability

Sample: Standard solution

Suitability requirements

Tailing factor: NMT 2.0

Relative standard deviation: NMT 5.0%

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of N-benzyl-N-methyl-ethanolamine in the portion of Injection taken:

Result = (rU/rS) × (CS/CU) × 100

rU	=	= peak response of N-benzyl-N-methyl-ethanolamine in the Sample solution
rS	=	= peak response of N-benzyl-N-methyl-ethanolamine in the Standard solution
CS	=	= concentration of USP N-Benzyl-N-methyl-ethanolamine RS in the Standard solution (mg/mL)
CU	=	= nominal concentration of nicardipine hydrochloride in the Sample solution (mg/mL)

Acceptance criteria: NMT 0.7%

• Organic Impurities

Solution A: 3.5 g/L of sodium perchlorate monohydrate in water. Add 1 mL/L of triethylamine, and adjust with perchloric acid to a pH of 2.0.

Solution B: Acetonitrile and methanol (700:300)

Mobile phase: See Table 2.

Table 2

Time (min)	Solution A (%)	Solution B (%)
0	70	30
15	70	30
55	35	65
60	35	65
62	70	30
70	70	30

Standard solution: 0.02 mg/mL of USP Nicardipine Hydrochloride RS in methanol prepared as follows. To a suitable amount of USP Nicardipine Hydrochloride RS add methanol to 60% of the final volume. Sonicate to dissolve. Cool, and dilute with methanol to volume. Pass the solution through a suitable filter of 0.45-µm pore size.

Sample solution: Nominally equivalent to 2 mg/mL of nicardipine hydrochloride in methanol from a suitable volume of Injection. Pass the solution through a suitable filter of 0.45-µm pore size. [Note—Sample solution is stable for about 42 h at 10

]

Chromatographic system

Mode: LC

Detector: UV 239 nm

Column: 4.6-mm × 15-cm; 5-µm packing L1

Flow rate: 1 mL/min

Temperatures

Column: 50

Sample: 10

Injection volume: 10 µL

System suitability

Sample: Standard solution

Suitability requirements

Tailing factor: NMT 2.0

Relative standard deviation: NMT 5.0%

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of each impurity in the portion of Injection taken:

Result = (rU/rS) × (CS/CU) × 1/F × 100

rU	=	= peak response of each impurity from the Sample solution
rS	=	= peak response of nicardipine from the Standard solution
CS	=	= concentration of nicardipine hydrochloride in the Standard solution (mg/mL)
CU	=	= nominal concentration of nicardipine hydrochloride in the Sample solution (mg/mL)
F	=	= relative response factor (see Table 3)

Acceptance criteria: See Table 3.

Table 3

Name	Relative Retention Time	Relative Response Factor	Acceptance Criteria, NMT (%)
Nicardipine monoacida	0.72	1.00	0.2
Nicardipinepyridine analogb	0.94	0.42	0.9
Nicardipine	1.00	1.00	—
Any unspecified degradation impurity	—	—	0.2
Total impuritiesc	—	—	3.5
a 5-(Methoxycarbonyl)-2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid. b 3-{2-[Benzyl(methyl)amino]ethyl} 5-methyl 2,6-dimethyl-4-(3-nitrophenyl)pyridine-3,5-dicarboxylate. c Total impurities include the sum of all organic impurities and N-benzyl-N-methyl-ethanolamine.

OTHER COMPONENTS

• Content of Sorbitol

Buffer: 1 g/L of tetrabutylammonium hydrogen sulfate in water

Mobile phase: Acetonitrile and Buffer (700:300)

Standard solution: 4.8 mg/mL of USP Sorbitol RS in Mobile phase. Pass the solution through a suitable filter of 0.45-µm pore size. Sonication may be necessary to aid in dissolution.

Sample solution: Nominally equivalent to 4.8 mg/mL of sorbitol in Mobile phase from the contents of NLT 3 injection vials. Pass the solution through a suitable filter of 0.45-µm pore size. [Note—Sample solution is stable for about 24 h.

]

Chromatographic system