磺胺类药物的毛细管高效液相色谱与电色谱研究

目的 研究毛细管高效液相色谱(μ-HPLC)和毛细管电色谱(CEC)分离磺胺类药物,建立药物微分离分析方法。方法 用ODS柱为固定相,甲醇和2 mmol·L^-1磷酸缓冲液（pH 3.0～7.0）为流动相,电压为0～-15 kV,流速为10 μL·min^-1,紫外检测波长254 nm。结果μ-HPLC在甲醇-2 mmol·L^-1磷酸缓冲液（30∶70）,pH 3.0时5种磺胺类药物实现基线分离;CEC在电压为-5 kV,甲醇-2 mmol·L^-1磷酸缓冲液（30∶70）,pH 5.0时5种磺胺类药物实现基线分离。结论电渗流随甲醇含量、缓冲液浓度增加而下降,随pH值、电压的增加而增加;溶质的保留值（k）随甲醇含量、缓冲液浓度、电压的增加而下降,随电压增加下降明显的是TMP,随pH值变化较复杂。在相同条件下对5种磺胺类药物的分离,μ-HPLC需67 min,CEC只需25 min,后者更适合于磺胺类药物的快速分离分析。

Study on separation of sulfonamides by capillary high-performance liquid chromatography and electrochromatography

AIM: To establish separation methods of five sulfonamides by using capillary high performance liquid chromatography(mu-HPLC) and electrochromatography. The effect of mobile phase varies such as methanol content, pH, buffer solution concentration and voltage on their chromatographic behavior and electroosmesis flow was investigated. Capillary electrochromatography (CEC) was compared with mu-HPLC at the same condition. METHODS: Stationary phase was ODS, mobile phase was methanol and 2 mmol.L-1 H3PO4 buffer solution (pH 3.0-7.0), voltage was 0- -15 kV, flow rate was 10 microL.min-1, pressure was approximately 70 MPa and UV detection wavelength was 254 nm. RESULTS: Separations on base line have been respectively accomplished for five sulfonamides by mu-HPLC with mobile phase of methanol-2 mmol.L-1 H3PO4 buffer solution (30:70) at pH 5.0 in 67 min, and CEC with the same mobile phase at -5 kV voltage in 25 min. CONCLUSION: Electroosmesis flow of CEC decreased with the increase in methanol content, buffer solution concentration, increased with the increase in voltage and increase slightly with the increase in pH of mobile phase. Retention values (k) of solutes to be examined decreased with increasing methanol content of mobile phase in mu-HPLC and CEC. Retention values (k) of solutes increased slightly with increasing buffer solution concentration, decreased with increasing voltage in CEC. Trimethoprim(TMP) decreased obviously with increasing voltage in CEC. The effect of pH of mobile phase on retention values (k) was more complex. Five sulfonamides were separated at the same mobile phase condition by mu-HPLC and CEC. And separation speed of CEC was much faster than that of mu-HPLC. CEC was very fit for rapid separation of sulfonamides.