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Insulin Slow Release Microsphere Preparation

Insulin Slow Release Microsphere Preparation

CD Formulation provides insulin slow release microsphere composition preparation services. This preparation method solves the problem that it has been impossible to produce spherical insulin nanospheres for a long time, and uses the oil-in-water - oil-in-solid (S/O/W) method to prepare microspheres by further microencapsulating the nanospheres in a slow release polymer. The surface of the prepared microspheres is smooth and round, with good homogeneity, regular and non-adhesive particles, high encapsulation rate, small sudden release and high drug loading capacity.

Insulin Slow Release Microspheres Preparation Technology

Insulin slow release microsphere technology uses oil-in-water - oil-in-solid (S/O/W) method to prepare microspheres by further encapsulating the nanospheres in a slow release polymer material, which can be prepared into a very regular micro-nanosphere composition, and can overcome the instability of insulin in the slow release material. The prepared micro-nanosphere compositions avoid the disadvantages of conventional W/O and W/O/W preparation methods such as low encapsulation rate, and severe sudden release of S/O/O, and environmental pollution. The size of microsphere compositions can be controlled according to different needs without polluting the environment; it can avoid the effect on insulin therapy, especially those with unstable physicochemical properties. The surface of micron spheres is smooth and round, and the particle size can be adjusted from 1 μm to 500 μm according to the needs.

Scanning electron micrographs of microspheres.Fig.1 Scanning electron micrographs of microspheres. (Manoharan et al., 2009)

How to Prepare Insulin Slow Release Microspheres

CD Formulation is committed to providing custom-made, high-quality insulin extended-release microspheres. The main biodegradable polymeric carrier materials used in the preparation of microspheres are: polylactic acid (PLA), polylactic acid glycolic acid (PLGA), polylactide, etc. Our materials can be selected according to customer needs to provide you with exclusive product solutions. We can provide evaluation of micron spheres along with customization of insulin extended release micron spheres to facilitate your subsequent drug formulation development.

Preparation steps of insulin slow release microspheres

1. Preparation of insulin nanosphere compositions

Zinc ionic compound (Zinc ionic compound is zinc acetate, zinc chloride, zinc sulfate, zinc bisulfate, zinc nitrate or zinc gluconate.) and dextran containing 0%-50% by weight of the insulin nanosphere composition are prepared into a solution of dextran and zinc ionic compound at a certain concentration, and then insulin is added dropwise to the solution. The well-mixed solution is pre-frozen in a freezer for 8-32 hours and lyophilized. The lyophilized powder is dissolved with polyethylene glycol (PEG) using organic solvent, and then the supernatant is removed by centrifugation, i.e., the organic solution of PEG, and repeated three times, and the insulin nanosphere composition is obtained by removing polyethanol (PEG) with organic solvent.

2. Insulin slow release micron sphere composition

The insulin nanosphere composition from step 1 was added to the organic solution of poly(lactic acid-hydroxyacetic acid) (PLGA), poly(lactic acid) (PLA), or polycaprolactone (PCL) to form a suspension. And then the suspension is emulsified by adding to sodium chloride solution and surfactant, and then cured by adding to sodium chloride solution, and the collected micron spheres are washed several times with water. After drying, the insulin slow release micron sphere composition is obtained.

Evaluation of insulin slow release microspheres

  • Morphological observation and particle size determination
  • Fourier infrared spectroscopy analysis of the microspheres
  • Determination of drug loading capacity and encapsulation rate of drug loaded microspheres
  • Differential scanning calorimetry analysis

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  1. Manoharan, C., & Singh, J. (2009). Insulin loaded PLGA microspheres: effect of zinc salts on encapsulation, release, and stability. Journal of pharmaceutical sciences, 98(2), 529-542.
Please note: Our products and services are not intended to be used directly in diagnostic or therapeutic procedures.
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