ABSTRACT
Enantioseparation of three β-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate) immobilized chiral stationary phase using supercritical fluid chromatography (SFC).The effect of organic modifiers (methanol,isopropanol and their mixture),col-umn temperature and back pressure on chiral separation of β-blockers was evaluated.Optimum chro-matographic separation with respect to resolution,retention,and analysis time was achieved using a mixture of CO2 and 0.1％ isopropyl amine in isopropanol:methanol (50:50,V/V),in 75:25 (V/V) ratio.Under the optimized conditions,the resolution factors (Rs) and separation factors (α) were greater than 3.0 and 1.5,respectively.Further,with increase in temperature (25-45 ℃) and pressure (100-150 bars)there was corresponding decrease in retention factors (k),α and Rs.However,a reverse trend (α and Rs)was observed for atenolol with increase in temperature.The thermodynamic data from van't Hoff plots revealed that the enantioseparation was enthalpy driven for metoprolol and propranolol while entropy driven for atenolol.To understand the mechanism of chiral recognition and the elution behavior of the enantiomers,molecular docking studies were performed.The binding energies obtained from simulation studies were in good agreement with the elution order found experimentally and also with the free energy values.The method was validated in the concentration range of 0.5-10 μg/mL for all the enan-tiomers.The limit of detection and limit of quantitation ranged from 0.126 to 0.137 μg/mL and 0.376-0.414 μg/mL,respectively.The method was used successfully to analyze these drugs in pharmaceutical preparations.
ABSTRACT
Background: Thyroid disorders constitute one of the most common endocrine disorders in pregnancy. However, there is no universal guidelines to screen every Pregnant Woman for Thyroid dysfunction in India. This study was conducted to evaluate the magnitude of thyroid dysfunction among ante natal mothers in a tertiary care centre.Methods: This was a cross sectional observational study conducted on ante natal mothers for a period of 6 months. All consecutive ante natal mothers in their first trimester were included in this study. Exclusion criteria was pre-gestational thyroid dysfunction, hypertension and diabetes mellitus. After obstetric examination and investigation, thyroid function test (Free T4 and TSH) was done in all patients.Results: Mean age of the patients enrolled was 26.2±3.54 years. Mean gestational age at which they underwent screening was 9±2 weeks. The mean BMI of the study patients was 21.7±4. The prevalence of hypothyroidism in antenatal mothers was 14.5%. 5 patients (5.5%) had hyperthyroidism. The calculated mean TSH value was 4.26 mIU/L.Conclusions: Universal screening for thyroid dysfunction during pregnancy should be made mandatory in India due to high prevalence, in order to prevent maternal and foetal complications.