• Assay Type Competitive ELISA
  • Sample Types Saliva, Urine, Water, Milk, Tissue Culture Media, Extracted Serum, Plasma (EDTA and Heparin), Fecal Extracts
  • Sensitivity 2.20 pg/mL
  • Species Levonorgestrel is identical across all species
  • Assay Duration 1.5 Hours
  • Samples/Plate 40 in Duplicate
  • Readout Colorimetric, 450 nm
  • Standard Curve The Levonorgestrel (LNG) ELISA Kit
  • Description

    Assay Principle: 

    The Levonorgestrel (LNG) ELISA Kit quantitatively measures LNG in saliva, urine, water, milk, tissue culture media, extracted serum, plasma (EDTA and Heparin), and fecal extracts. The Levonorgestrel (LNG) ELISA Kit is a competitive ELISA with a run time of 1.5 hours. Please read the complete kit insert for more information before performing this assay.

    Use our provided LNG standard to generate a standard curve for the assay. Pipette the standards or diluted samples into a transparent microtiter plate coated with our goat anti-rabbit IgG antibody. Add the LNG peroxidase conjugate and the LNG polyclonal rabbit antibody. Then incubate the mixture covered at room temperature, shaking for 1 hour. The immunological reaction occurs between the anti-LNG antibody, the LNG antigen in the sample or standard, and the LNG-peroxidase conjugate. As the LNG concentration in the sample increases, the bound LNG-peroxidase conjugate decreases, causing a decrease in signal and vice versa. 

    After the 1-hour incubation, wash away the excess LNG-peroxidase conjugate and add the TMB substrate. The TMB substrate reacts with the bound LNG-peroxidase conjugate generating a signal detected by a plate reader at 450nm. Use the intensity and the standard curve to calculate the LNG concentration in the samples.


    Levonorgestrel (LNG) is a synthetic steroid commonly used for contraception, dysmenorrhea treatment, and endometrial protection during estrogen replacement therapy in postmenopausal women. LNG is an effective treatment modality for various gynecologic conditions, including heavy menstrual bleeding, pelvic pain, endometrial hyperplasia, and early-stage endometrial cancer. LNG is safe to use while breastfeeding and works by decreasing ovulation and changing the mucus in the cervix to prevent the passage of sperm and altering the uterine lining. Quantitative measurement of LNG in biological samples can help determine if target therapeutic concentrations are being met and maintained. LNG can also be measured in environmental samples using this kit. Environmental LNG can have toxic effects on aquatic ecosystems.

  • Structure