In vitro evaluation of compression-coated glycyl-L-histidyl-L-lysine-Cu(II) (GHK-Cu2+)-loaded microparticles for colonic drug delivery.
Uğurlu. Timuçin T; Türkoğlu. Murat M; Özaydın. Tuğçe T
Key Findings
- Surfactant ratio influences production yield, while cross‑linker concentration does not.
- Entrapment efficiency ranged from ~58% to 78%, improving with higher drug‑loading but dropping with more cross‑linker.
- Optimal formulation (F8) released 50‑80% of the peptide within 4 h and, when coated with 700 mg of hydroxypropyl cellulose, gave a 6‑hour lag before release, suitable for colonic delivery.
Practical Outcomes
- For most DIY health enthusiasts, the work is too technical and equipment‑heavy to apply directly. It mainly informs formulation scientists that a high‑viscosity HPC coat can create a delayed‑release GHK‑Cu tablet, but it does not provide a usable dosing protocol or clear health benefit for self‑experimentation.
Summary
Scientists made tiny particles that hold the GHK‑Cu peptide and coated them so they release the peptide in the colon after about 6 hours. The study shows which formulation tweaks (like surfactant amount, cross‑linker level, and coating thickness) affect how much peptide is trapped and how quickly it comes out.
Abstract
Glycyl-L-histidyl-L-lysine-Cu(II) (GHK-Cu(2+))-loaded Zn-pectinate microparticles in the form of hydroxypropyl cellulose (HPC) compression-coated tablets were prepared and their in vitro behavior tested. GHK-Cu(2+) delivery to colon can be useful for the inhibition of matrix metalloproteinase, with the increasing secretion of tissue inhibitors of metalloproteinases (TIMPS),which are the major factors contributing in mucosal ulceration and inflammation in inflammatory bowel disease. The concentration of peptide was determined spectrophotometrically. The results obtained implied that surfactant ratio had a significant effect on percent production yield (1.25 to 1.75 w/w; 72.22% to 80.84%), but cross-linking agent concentration had not. The entrapment efficiency (EE) was found to be in the range of 58.25-78.37%. The drug-loading factor significantly increased the EE; however, enhancement of cross-linking agent concentration decreased it. The release of GHK-Cu(2+) from Zn-pectinate microparticles (F1-F8) in simulated intestinal fluid was strongly affected by cross-linking agent concentration and drug amount (50 mg for F1-F6; 250 mg for F7-F8), but not particularly affected by surfactant amount. Release profiles represented that the microparticles released 50-80% their drug load within 4 h. Therefore, the optimum microparticle formulation (F8) coated with a relatively hydrophobic polymer HPC to get a suitable colonic delivery system. The optimum colonic delivery tablets prepared with 700 mg HPC-SL provided the expected delayed release with a lag time of 6 h. The effects of polymer viscosity and coat weight on GHK-Cu(2+) release were found to be crucial for the optimum delay of lag time. The invention was found to be promising for colonic delivery.
Study Information
pubmed
2011
2011-04-04T00:00:00.000Z
10.3109/03639045.2011.569934
4
34