A Fast, Simple and Sensitive Method for Estimation of Leuprolide in Human Plasma using Shimadzu LCMS-8045

User Benefits

- Rapid, simple and sensitive method with LLOQ of 25 pg/mL. - Low plasma volume helps to reduce matrix effect and increase the lifespan of column and LCMS. - The single-step SPE method helps boost overall productivity, save time, and reduce errors.

Introduction

1. Introduction Leuprolide acetate is a synthetic nonapeptide analog of naturally occurring gonadotropin releasing hormone (GnRH or LH-RH). The analog possesses greater potency than the natural hormone. The chemical name is 5-oxo-L-prolyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosyl-D-leucyl-L-leucyl-L-arginyl-N-ethyl-L-prolinamide acetate (salt). Leuprolide also known as Leuprorelin acetate, is orally inactive and generally given subcutaneously or intramuscularly. Leuprorelin may be used in the treatment of hormone-responsive cancers such as prostate cancer and breast cancer. It may also be used for estrogen-dependent conditions such as endometriosis or uterine fibroids. It may be used for precocious puberty in both males and females, and to prevent premature ovulation in cycles of controlled ovarian stimulation for in vitro fertilization. It may be used to reduce the risk of premature ovarian failure in women receiving cyclophosphamide for chemotherapy) . The peptide drug is released from the depot formulations at a functionally constant daily rate for 1, 3, or 4 months, depending on the polymer type [polylactic/glycolic acid (PLGA) for a 1-month depot and polylactic acid (PLA) for depot of >2 months], with doses ranging between 3.75 and 30mg. Mean peak plasma leuprorelin concentrations of 13.1, 20.8 to 21.8, 47.4, 54.5 and 53 μg/L occur within 1 to 3 hours of depot subcutaneous administration of 3.75, 7.5, 11.25, 15 and 30 mg, respectively, compared with 32 to 35 μg/L at 36 to 60 min after a subcutaneous injection of 1mg of a non-depot formulation. Sustained drug release from the PLGA microspheres maintains plasma concentrations between 0.4 and 1.4 μg/L over 28 days after single 3.75, 7.5 or 15mg depot injections) . It indicates that the method required for pharmacokinetic evaluations need to achieve a sensitivity limit of sub-picogram level as low as 400 pg/mL. Such a method should address many problems posed by peptides viz., poor ionization, non-specific adsorption, carry-over, and low extraction recovery. We have therefore developed a method with high chromatographic resolution and ample sensitivity giving the lowest limit of quantification (LLOQ) of 25 pg/mL for leuprolide in human plasma using LCMS-8045. The method was developed keeping some key criteria in focus- namely simpler extraction procedure, highly optimized chromatography, and enhanced sensitivity. These factors enable selective and high-throughput analysis of leuprolide for the pharmacokinetic investigation

26 de junio de 2024 GMT