High-Sensitivity Chemiluminescence Assay for Human Growth Hormone — Bulk Reagent & Matched Antibody Pair for OEM Platform Integration
Human growth hormone (hGH), secreted by the anterior pituitary gland, is a critical regulator of growth, metabolism, and body composition. Accurate quantification of circulating hGH is essential for diagnosing growth hormone deficiency (GHD) in children and adults, monitoring acromegaly and gigantism, and conducting stimulation or suppression testing.
Sekbio's hGH CLIA bulk reagent is a one-step competitive chemiluminescence immunoassay built on the acridinium ester (AE) platform, offering 0.07 ng/mL analytical sensitivity with an intra-assay CV of 1.41% at low concentrations. The magnetic bead separation format delivers rapid kinetics in a 15-minute assay protocol, directly compatible with automated CLIA analyzers.
The matched anti-hGH antibody pair (hGH-041 + hGH-042) — both mouse IgG1 clones purified by Protein A affinity chromatography — is available as standalone OEM raw material for integrating hGH quantification into CLIA, LFA, and ELISA assay platforms.
Chemiluminescence immunoassay on the AE platform delivers the sensitivity, precision, and dynamic range required for accurate hGH measurement across the full clinical concentration spectrum.
The acridinium ester (AE) chemiluminescence signal generates extremely low background noise, enabling a limit of detection of 0.07 ng/mL (S/N = 9.0). This sensitivity covers the post-stimulation nadir values critical for GHD diagnosis, where hGH levels may be suppressed to near-undetectable concentrations.
From 0.07 ng/mL to 47.52 ng/mL, the assay delivers a signal-to-noise range exceeding 16,800-fold. This single assay format covers both the normal physiological range (0.1–5 ng/mL in adults) and the markedly elevated levels seen in active acromegaly (>10 ng/mL) — without the dilution steps required by narrower-range assays.
Intra-assay CV of 1.41% at the low control level (1.24 ng/mL) and 3.89% at the high level (19.85 ng/mL), based on 10 replicate measurements. This level of precision is required for serial monitoring in acromegaly and for interpreting growth hormone stimulation tests where small concentration changes carry clinical significance.
The Ra component uses magnetic beads as the solid phase, enabling rapid, efficient separation of bound from free label in a fully automated format. Magnetic bead kinetics are significantly faster than conventional microplate or tube-based separation — contributing to the 15-minute total assay time and compatibility with high-throughput CLIA analyzers.
Accelerated stability testing at 37°C for 1, 4, and 7 days showed calibrator signal deviations of ≤10.10% from the 2–8°C reference condition. All calibration levels maintained stable signal-to-background relationships throughout, demonstrating robust reagent stability under thermal stress.
The hGH CLIA reagent is supplied as a bulk system (Ra magnetic bead reagent + Rd AE-labeled reagent + optional lyophilized calibrators), ready for direct integration into automated CLIA analyzers. The matched antibody pair (hGH-041 + hGH-042) is additionally available as standalone components for custom assay development.
Complete analytical performance characterization: six-point calibration, precision at two levels, dilution linearity, and accelerated stability testing.
Six calibrators from 0 to 47.52 ng/mL, each measured in triplicate. Signal-to-noise (S/N) calculated relative to the zero calibrator (S0). The assay delivers a monotonic response across the entire calibration range with S/N exceeding 16,000× at the upper limit.
| Calibrator (ng/mL) | RLU Rep 1 | RLU Rep 2 | RLU Rep 3 | Average RLU | S/N |
|---|---|---|---|---|---|
| 0.00 (Blank) | 156 | 298 | 154 | 203 | 1.00 |
| 0.07 (LOD) | 1,786 | 1,863 | 1,824 | 1,824 | 9.00 |
| 1.24 | 64,597 | 61,922 | 63,151 | 63,223 | 311.96 |
| 10.72 | 911,014 | 952,503 | 930,147 | 931,221 | 4,594.84 |
| 19.85 | 1,664,619 | 1,676,046 | 1,671,145 | 1,670,603 | 8,243.11 |
| 47.52 | 3,333,857 | 3,496,728 | 3,414,875 | 3,415,153 | 16,851.09 |
| Reaction: 30 µL Ra + 15 µL sample + 30 µL Rd, 15 min incubation, wash, 100 µL Pre-Trigger (A) + 100 µL Trigger (B), read RLU. S/N = Average RLU / Blank RLU. | |||||
Repeatability assessed at a clinically relevant low concentration (1.24 ng/mL, near the lower limit of normal adult range) and a high concentration (19.85 ng/mL, within the acromegaly range). Both CV values meet the ≤5% precision target required for clinical chemistry applications.
| Level | Target (ng/mL) | n | Mean RLU | SD (RLU) | CV% (RLU) | Mean C (ng/mL) | SD (ng/mL) | CV% (Conc.) |
|---|---|---|---|---|---|---|---|---|
| Low | 1.24 | 10 | 64,051 | 1,240 | 1.94% | 1.21 | 0.02 | 1.41% |
| High | 19.85 | 10 | 1,677,792 | 61,039 | 3.64% | 19.05 | 0.74 | 3.89% |
| CV% (Conc.) is the clinically relevant metric — calculated from back-calculated concentrations using the calibration curve. Low level: individual replicates ranged 1.19–1.23 ng/mL. High level: 17.73–20.25 ng/mL. | ||||||||
A high-concentration sample (47.17 ng/mL) was serially diluted to generate six concentrations from 0.08 to 47.17 ng/mL. Back-calculated concentrations from the calibration curve confirm accurate, proportional response across the full assay range.
| Expected (ng/mL) | Dilution Factor | RLU Rep 1 | RLU Rep 2 | RLU Rep 3 | Average RLU | Measured C (ng/mL) |
|---|---|---|---|---|---|---|
| 0.08 | 0.0 | 2,145 | 2,170 | 2,280 | 2,198 | 0.08 |
| 9.50 | 0.2 | 720,551 | 690,599 | 729,731 | 713,627 | 8.44 |
| 18.92 | 0.4 | 1,491,787 | 1,481,308 | 1,473,674 | 1,482,256 | 16.73 |
| 28.34 | 0.6 | 2,141,373 | 2,202,921 | 2,126,778 | 2,157,024 | 25.32 |
| 37.75 | 0.8 | 2,845,453 | 2,945,456 | 2,897,845 | 2,896,251 | 37.53 |
| 47.17 | 1.0 (Neat) | 3,229,481 | 3,458,077 | 3,314,012 | 3,333,857 | 47.17 |
| Linearity confirmed across the full calibration range. Back-calculated concentrations track closely to expected values at all dilution levels. | ||||||
Reagent stability was assessed by comparing signal levels at 37°C (1, 4, and 7 days) to the 2–8°C reference (control storage). Deviation is calculated as percentage change in average RLU from the control condition. Three random serum samples were included alongside calibrators.
| Calibrator (ng/mL) | 2–8°C Control (Avg RLU) | 37°C · 1 Day (Dev%) | 37°C · 4 Days (Dev%) | 37°C · 7 Days (Dev%) |
|---|---|---|---|---|
| 0.07 | 1,742 | −3.04% | −2.55% | −10.10% |
| 1.24 | 66,929 | −2.09% | −3.43% | −4.79% |
| 10.72 | 908,561 | −0.02% | +0.02% | −0.86% |
| 19.85 | 1,602,942 | −0.44% | −0.14% | −0.43% |
| 47.52 | 3,428,036 | +0.23% | +0.01% | −1.03% |
| Random serum 1 | 3,529 | −6.48% | −2.61% | −7.95% |
| Random serum 2 | 448 | +7.81% | −1.45% | −6.81% |
| Random serum 3 | 8,775 | −5.02% | −6.65% | −8.49% |
| Maximum deviation at 37°C for 7 days: −10.10% (at 0.07 ng/mL calibrator). All mid-to-high calibrators maintained ≤5% deviation over 7 days. 37°C/7 days approximates extended 2–8°C stability; data supports robust on-board reagent stability for automated analyzer applications. | ||||
Two independently cloned mouse IgG1 monoclonal antibodies targeting human growth hormone — available as standalone OEM raw materials for CLIA, LFA, and ELISA immunoassay development.
In the one-step competitive CLIA format demonstrated in the performance report, hGH-041 and hGH-042 function as the paired antibodies: one clone is immobilized on the magnetic bead (Ra component) as the capture antibody, and the other is conjugated to acridinium ester (Rd component) as the tracer. Sample hGH competes with the tracer for the limited capture antibody sites — generating an inverse dose-response curve where higher hGH concentration produces lower RLU signal.
Both antibodies are supplied in physiological saline (0.9% NaCl) compatible with standard conjugation chemistries for AE labeling and magnetic bead coupling without buffer exchange in most protocols. Contact Sekbio for lot-specific concentration data and pairing orientation recommendations.
The hGH CLIA reagent and antibody pair support the full range of clinical growth hormone testing and OEM assay development needs.
GHD diagnosis requires stimulation testing (insulin tolerance test, glucagon, arginine) where hGH must exceed a threshold of 5–10 ng/mL to exclude deficiency. The 0.07 ng/mL LOD and 1.41% low-level CV ensure accurate measurement at both the subnormal post-stimulus nadir and the diagnostic peak — critical for unambiguous GHD classification.
Oral glucose suppression testing (OGTT) for acromegaly requires hGH to fall below 1 ng/mL in healthy subjects. The assay's wide range (to 47.52 ng/mL) captures elevated pre-treatment acromegaly levels, while its low CV at 1.24 ng/mL enables accurate detection of suppression threshold — all within a single assay format.
The bulk reagent format (Ra magnetic bead + Rd AE reagent + lyophilized calibrators) is designed for direct integration into automated chemiluminescence analyzers. The 15-minute incubation time, magnetic bead separation, and standardized 30/15/30 µL reagent volumes are compatible with common high-throughput CLIA platform protocols.
hGH-041 and hGH-042 are available as OEM antibody raw materials for building custom hGH immunoassay kits. Both IgG1 clones cover independent epitopes and have been validated in the competitive CLIA format. Developers building CLIA, FIA, or ELISA kits for clinical analyzers can use these clones directly as capture/tracer antibody pairs without additional epitope screening.
Understanding growth hormone biology and the analytical requirements for accurate clinical measurement.
hGH is secreted in pulsatile bursts and varies markedly by age, sex, nutritional status, and time of day. Clinical testing uses stimulation or suppression protocols to interrogate the dynamic range of pituitary hGH secretory capacity rather than relying on a single random measurement.
| Clinical Context | Typical hGH Range | Diagnostic Significance | Assay Requirement |
|---|---|---|---|
| Fasting baseline (healthy adult) | <5 ng/mL | Normal pituitary function | Low-level precision |
| Post-stimulation peak (GHD excluded) | >5–10 ng/mL | Normal GH response | Mid-range accuracy |
| Post-stimulation peak (GHD confirmed) | <3–5 ng/mL | Growth hormone deficiency | Low-level sensitivity ≤0.1 ng/mL |
| Random measurement, acromegaly | >10–100 ng/mL | Excess GH secretion | Wide upper range |
| OGTT nadir (acromegaly excluded) | <1 ng/mL | Normal GH suppression | Low-level CV ≤5% |
| Children, peak growth phase | 0.1–20 ng/mL | Pediatric growth assessment | Full range coverage |
| Sekbio's hGH CLIA covers 0.07–47.52 ng/mL — spanning all clinical decision points from the GHD diagnostic threshold to moderate-severity acromegaly in a single calibration curve. | |||
Multiple immunoassay platforms are used for clinical hGH quantification. CLIA on the AE/magnetic bead platform offers the best combination of sensitivity, dynamic range, speed, and automation compatibility for routine clinical laboratory use.
| Platform | Typical LOD | Precision (CV) | Throughput | Key Limitation |
|---|---|---|---|---|
| RIA (Radioimmunoassay) | 0.1–0.5 ng/mL | 5–10% | Low (batch) | Radioactive waste; regulatory burden |
| ELISA (Microplate) | 0.1–0.5 ng/mL | 5–15% | Medium | Manual processing; matrix effects |
| FIA (Fluorescence) | 0.05–0.2 ng/mL | 3–8% | Medium–High | Autofluorescence background |
| CLIA — AE / Magnetic Bead (Sekbio) | 0.07 ng/mL | 1.41–3.89% | High (automated) | Requires CLIA analyzer instrument |
| Electrochemiluminescence (ECL) | 0.05–0.1 ng/mL | 2–5% | High | Proprietary platform dependency |
| Sekbio hGH CLIA achieves LOD and CV comparable to ECL platforms while offering a bulk reagent format compatible with multiple CLIA analyzer brands — without single-vendor platform lock-in. | ||||
Request the CLIA bulk reagent performance datasheet, antibody pair technical data, or OEM supply information from our team.