Biocompatible drug-delivery materials are important because they provide controlled release of biologically active agents to enhance the effectiveness of medical treatments. Montmorillonite (Mnt) has been utilized in drug-delivery systems for delayed-release application because it can safely encapsulate drug molecules via intercalation reactions. The objective of the present study was to evaluate the delivery characteristics of the drug ciprofloxacin (CIP) from a composite with Mnt (Mnt-CIP) in which the Mnt was first prepared by acid treatment and vibration ball milling. The surfaces of Mnt were modified by reacting the Mnt suspension in 1.0 M HCl acid and by dispersing the powder with a vibration ball mill, then the CIP drug was added at pH 4 and stirred. The goal was to improve the sustained-release performance of the CIP. This Mnt-CIP drug-release system was characterized by X-ray diffraction, X-ray fluorescence analysis, Fourier-transform infrared spectroscopy, surface area measurement using the Brunauer-Emmett-Teller (BET) method, and ultraviolet spectroscopy. The X-ray diffraction results confirmed the intercalation of CIP into the interlayer space of Mnt. The in vitro release properties of the intercalated CIP were investigated using a simulated phosphate-buffered saline solution (pH 7.4) at 36±0.5°C. The CIP drug exhibited a continued release for 3 h. Moreover, Mnt prepared by HCl acid treatment and dispersion in the vibration ball mill delayed the drug dissolution rate. In summary, the Mnt-CIP composite prepared in this study exhibited slow and sustained release characteristics, indicating that Mnt mined from the Gampo-40 mining area in Gyeongju can be used in various drug-delivery applications.

Focus here is placed on the pharmaceutical and biomedical applications of novel clay-drug hybrid materials categorized by methods of administration. Clay minerals have been used for many years as pharmaceutical and medicinal ingredients for therapeutic purposes. A number of studies have attempted to explore clay-drug hybrid materials for biomedical applications with desired functions, such as sustained release, increased solubility, enhanced adsorption, mucoadhesion, biocompatibility, targeting, etc. The present review attempts not only to summarize the state-of-the-art of clay-drug hybrid materials and their advantages, depending on the methods of administration, but also to deal with challenges and future perspectives of clay mineral-based hybrids for biomedical applications.

Bentonite-based tablets offer multiple advantages over other types of formulated tablets, including being biocompatible and cost-effective, and they can be used to develop gel-like matrices that have potential for use in sustained-release formulations. Developing a high-load sustained-release formulation has been reported to be challenging; therefore, the aim of this study was to develop systematically bentonite-based sustained-release tablets for a high-load active agent (ibuprofen) and investigate their release kinetics. Ibuprofen-loaded tablets (800 mg) were prepared using wet and dry granulation followed by enteric coating of the tablets. Fourier-transform infrared spectroscopy, differential scanning calorimetry and X-ray powder diffraction were used to evaluate the compatibility of ibuprofen with bentonite. The results show that these tablets comply with compendial requirements. In addition, the release profile of the formulations reveals that the drug follows a non-Fickian release model. The present formulation demonstrates a new use of bentonite as a safe and cost-effective excipient with adequate binding and compaction for preparing sustained-release tablets.

The objective of this study was to understand the effects of ceramic polymer composite and pH of the surrounding vicinity on the release kinetics of doxorubicin. Different concentrations of polymers with polycaprolactone (PCL), poly glycolic lactic acid (PLGA), and a blend of PCL–PLGA with hydroxyapatite (HA) were investigated for doxorubicin release at physiological pH of 7.4 and an acidic pH of 5.0 caused by immediate surgery. Burst release of 20% was observed from bare HA at pH 7.4 over a week, whereas all the polymer incorporated discs showed sustained release. The hydrophilic–hydrophobic and hydrophobic–hydrophobic interactions between the polymer and the drug altered by the surrounding pHs were found to be pivotal in controlling the release kinetics of drug. No cytotoxicity of the drug at a concentration of 50 μg per disc was observed at early time points when cultured with osteoblast cells; however, the same drug dosage inhibited osteosarcoma cell viability. This study mainly bases on the comprehension of the effects of chemistry, environment, and polymer–drug interactions, leading to a beneficial understanding towards the design of drug delivery devices.

In this study, the advantage of the use of chloroquine (CQ) containing liposomes (lipCQ) over free CQ in the chemotherapy of murine malaria (Plasmodium berghei) was demonstrated. The maximum permissible dose per intraperitoneal injection was 0·8 and 10 mg for CQ and lipCQ, respectively. An increase in therapeutic and prophylactic efficacy of lipCQ in comparison with free CQ at a 0·8 mg CQ dose level was found. It was possible to obtain 100% efficacy (injection at day 5 after infection; parasitaemia 4–8%) with one single intraperitoneal injection of 6 mg lipCQ. Moreover, the ability to increase the doses of CQ per injection after liposome encapsulation allowed successful treatment of infections with CQ-resistant Plasmodium berghei which could not be cured by a 7-day course with the maximum tolerable dose of free CQ of 0·8 mg/mouse/day.

As sustained methylphenidate becomes available in the United Kingdom, there is likely to be considerable demand related to the difficulties that frequently arise with standard methylphenidate due to the need for midday doses at school, as well as the pronounced ‘on/off’ therapeutic effects sometimes seen with multiple doses. This article briefly discusses longer acting stimulants, reviews the available literature, anticipates possible problems in the use of slow release methylphenidate, and presents clinical guidelines for its use.