Study On Mcm-41 As Drug Carrier Material

Drug release is to combine drug active molecules and carriers by physical or chemical methods, and drug active molecules are released continuously with appropriate concentration in human body by the way of diffusion and permeation control to achieve the purpose of bringing drug efficacy into full play. Drug carriers are just to achieve this goal, which is a new form of drug delivery combined with pharmacy, materials science, and clinical development. Drug carriers are an important part of drug delivery system, also a main factor affecting drug efficacy. Drug delivery system plays an important role in maintaining plasma level, reducing times of drug administration, lowering toxicity of drug and improving drug efficacy. To obtain the ideal release behavior, the carrier material should have good biocompatibility, biodegradability, physicochemical property, biological stability and low toxicity.MCM-41 molecular sieves have regular pore texture, chemical homogeneous nature, larger specific surface area and pore volume of inorganic particles, which have not pharmacological activity, nontoxicity, can be recycled repeatedly, and their surface can be functionalized. They can not only adjust drug loading, but also effectively control the release rate of drug molecules to achieve the purpose of slow-release drug.In this thesis, different MCM-41 molecular sieves were synthesized by hydrothermal synthesis method. Different model drugs of nitrendipine, amoxicillin and captopril were doped inside the pore channels of the molecular sieves via liquid-phase grafting method. The structures of the prepared materials were characterized and analyzed by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), low temperature nitrogen adsorption-desorption technique at 77 K, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Timely detection on the release process of the prepared drugs in a simulated body fluid (SBF) solution was made. The main results obtained were as follows:(1) MCM-41 molecular sieves were modified with trimethylchlorosilane before calcination. Nitrendipine was doped inside the pore channels of the unmodified MCM-41 and the modified MCM-41 molecular sieves, and MCM-41 molecular sieves still kept the characteristic of mesoporous pore. The timely detection on the release process of the prepared drugs in a simulated body fluid (SBF) solution was studied. The results showed that the process was divided into four stages. It was observed that the samples showed a sharp initial release burst after 2 h for unmodified MCM-41 molecular sieves as carrier (MN) sample, and 1 h for modified MCM-41 molecular sieves as carrier (MMN) sample. The drug carriers which were prepared by the way of modification before calcination, could make drugs be doped mainly into the channels of molecular sieves, and also make the process of drug release slower. The release rate of MN sample reached to 51.4% at 5 h, and 99.6%at 30 h. The release rate of MMN sample reached to 51.4%at 7 h, and 99.7% at 34 h.(2) Two different particle size MCM-41 molecular sieves were synthesized under different synthetic parameters, and the prepared molecular sieves were used as the carriers of amoxicillin drug. From the timely detection on the release process of the prepared drugs in a SBF solution, it was found that the amoxicillin drug was very rapidly released from the carrier during the first 3 h. After that, the release rate changed slowly. After 36 h, the release rate of the small-particle MCM-41-amoxicillin sample (SA) was 99%, and the release rate of big-particle MCM-41-amoxicillin sample (BA) was 98%. Compared with the SA sample, the BA sample was released more rapidly in the first 3 h. However, it became slower after further released.(3) Two different porous size MCM-41 molecular sieves were synthesized under the different template reagents, and the prepared molecular sieves were used as the carriers of captopril drug. From the timely detection on the release process of the prepared drugs in a SBF solution, it was found that the captopril drug was very rapidly released from the carrier during the first 1 h. After that, the release rate changed slowly. For the big porous MCM-41-captopril sample (BC), the release rate reached to 50% at 12 h, and was 89% at 36 h. For the small porous MCM-41-captopril sample (SC), it was 53% at 5 h, and was 99% at 24 h.