Parathyroid Hormone Microneedle Patch Preparation

The main function of parathyroid hormone (PTH) is to regulate calcium and phosphorus metabolism in vertebrates, resulting in increased blood calcium levels and decreased blood phosphorus levels. At present, PTH is a large protein drug, and its administration route is still limited to injection due to its poor stability, which causes great inconvenience when administered frequently.

Microneedle preparation steps

1. Preparing a polymer solution containing PTH as the microneedle composition material.
2. Casting said polymer solution containing PTH onto a mold with an array of micropores.
3. Coating the mold with a polyvinyl alcohol adhesive layer.
4. Attaching a prefabricated backing layer to the back of the cast microneedles.
5. Freezing and thawing and removing the mold.
6. Dry the microneedle patch.

Service Details for Parathyroid Hormone Microneedle Patch Preparation

• Polymer Material

The polymer material chosen for microneedles is PVA, which is widely used in the field of pharmacy and has good skin compatibility.

• The principle of filling microporous and material requirements

The principle of filling micropores using pressure difference can be operated by evacuation or centrifugation.

The mold material is a hydrophobic polymer mold with microporous arrays, which has a breathable and impermeable microporous structure. Due to the air permeability, the polymer solution can be filled with micropores only when vacuum is applied; secondly, the mold material should be hydrophobic to avoid the microneedles sticking to the mold when separating the microneedles from the mold and destroying the needle shape. The mold material used is polytetrafluoroethylene.

Performance Evaluation of Parathyroid Hormone Microneedles

PTH microneedle release profile test

PTH microneedles were placed in a Franz diffusion cell device with a release solution of PBS, stirred at a rotational speed, and the top of the microneedles were covered with plastic film, sampled at regular intervals, and the PTH concentration was measured with a PTH-ELISA kit. And then, the cumulative release curve of PTH is calculated, which in turn allows the evaluation of the drug release process.

Skin test

This test can be performed by pressing the microneedle on the skin skin of the rat and after a certain period of time, the trace of the microneedle is observed.

Advantages of Parathyroid Hormone Microneedle Preparation

• The backing layer is prepared using the same polymer solution as the needle tip, with polyvinyl alcohol as the constituent material of the backing film supporting the microneedle fractions, allowing the backing layer to be tightly bonded to the microneedle tip so that the backing film and the needle tip can be consistently detached from the mold when the film is uncovered and there are no problems with needle breakage during the process.
• The choice of hyaluronic acid increases the swelling capacity of the prescription and improves the rate of drug release and the efficiency of transdermal absorption.