临床常用咖啡因作为早产新生儿的呼吸兴奋剂。一种医院自制的口服制剂含咖啡因10mg/ml及1 mg/ml的山梨酸钾防腐剂。使用100 mm×4.5 mm Spherisorb 5.μm己基反相柱。流动相为12％乙腈在0.1mol/L乙酸钠缓冲液(pH 4.5)中,流速2ml/min,注射体积为20μl,UV检测波长258 nm。咖啡因口服液(1.0 g)用水稀释至25ml。取该溶液5 ml,加入5 ml含3 mg/ml苔黑酚单水合物(内标)的水溶液,该混合物 Clinical caffeine as a preterm neonatal respiratory stimulants. A hospital-made oral preparation containing potassium sorbate preservatives at caffeine 10 mg / ml and 1 mg / ml. A 100 mm × 4.5 mm Spherisorb 5. μm hexyl reverse phase column was used. The mobile phase consisted of 12% acetonitrile in 0.1mol / L sodium acetate buffer (pH 4.5), flow rate 2ml / min, injection volume 20μl, UV detection wavelength 258 nm. The caffeine oral solution (1.0 g) is diluted with water to 25 ml. Take 5 ml of this solution and add 5 ml of an aqueous solution containing 3 mg / ml cethenol monohydrate (internal standard), the mixture