Photoresponsive polymeric microneedles: An innovative way to monitor and treat diseases.

Microneedles (MN) technology is an emerging technology for the transdermal delivery of therapeutics. When combined with photoresponsive (PR) materials, MNs can deliver therapeutics precisely and effectively with enhanced efficacy or synergistic effects. This review systematically summarizes the therapeutic applications of PRMNs in cancer therapy, wound healing, diabetes treatment, and diagnostics. Different PR approaches to activate and control the release of therapeutic agents from MNs are also discussed. Overall, PRMNs are a powerful tool for stimuli-responsive controlled-release therapeutic delivery to treat various diseases.

Leonurus japonicus Houtt. (Motherwort): Systematic research through chemical profiling, stability under controlled conditions and pharmacokinetic analysis on screening Q-markers for quality control.

Leonurus japonicus Houtt. (Motherwort) is the fresh or dried aerial part of Leonurus japonicus Houtt. (Labiaceae), which is widely used in clinical practice and daily life, used to treat gynecological diseases. However, the differences between different parts, single index component in Pharmacopoeias and the less stability of active ingredients affect its clinical efficacy. This study aimed to find the multi-active compounds between different parts of Motherwort to ensure its clinical efficacy, which related to stability and had pharmacokinetic behavior. Firstly, HPLC-Q-TOF-MS/MS was used to analyze the components in vitro and in vivo, as well as multivariate statistical analysis and network pharmacology analysis was conducted to find the significant different components related to activity. Secondly, the content determination methods were established to study the stability of effective components during storage in order to establish the content limit for quality control of Motherwort. Thirdly, UFLC-MS/MS was used to analyze the pharmacokinetic behavior of active components in Motherwort. The results showed that a total of 131 chemical constituents were identified in vitro and 21 prototype absorption compounds and 72 metabolites were found in vivo. Meantime, multivariate statistical analysis and network pharmacology analysis was combined to find that leonurine, stachydrine and trigonelline were activity-related substance, which could be used as active components related to pharmacodynamics in different parts. Then the stability variation trend and content limit of three alkaloids were found, which could be used for the quality control of Motherwort. Furthermore, the results showed that three alkaloids had pharmacokinetic behavior in vivo. 3 alkaloids were screened, which could be used as active components most closely related to pharmacodynamics among different parts. The stable stage, assay tolerance and pharmacokinetic characteristics were studied by the active substances, which could provide a basis for quality control and clinical medication of Motherwort.

A simple and cost-effective approach to fabricate tunable length polymeric microneedle patches for controllable transdermal drug delivery.

Polymeric microneedles (MNs) are attractive transdermal drug delivery systems because of their efficient drug delivery and minimal invasiveness. Master template fabrication is the most time-consuming and costly step in producing polymeric MNs using a micromoulding approach. Herein, this issue is addressed by modifying tattoo needle cartridges by adjusting the volume of a PDMS spacer, thus streamlining polymeric MN fabrication and significantly reducing its manufacturing cost. Using the fabricated master template, dissolvable polymeric MN systems containing poly(vinyl pyrrolidone) (PVP) and poly(vinyl alcohol) (PVA) were developed. This MN system exhibits several advantages, including controllable MN length, uniform distribution of each needle, and controllable drug release profiles. Overall, polymeric MN fabrication using this method is inexpensive, simple, and yields controllable and effective transdermal drug delivery.

Polymeric microneedles for controlled transdermal drug delivery.

Polymeric microneedle (MN) systems are interesting transdermal drug delivery systems because of their controlled drug delivery, tunable properties, and ease of patient self-administration. They are biocompatible and can easily and painlessly penetrate the stratum corneum, delivering their contents into the dermis where they can be adsorbed into systemic circulation. Polymeric MNs can facilitate appropriate therapeutic dosing by controlling the release kinetics of pre-loaded drugs, targeting specific tissues, or responding to changing physiological conditions. This can be accomplished by modifying the degradation and swelling profiles of the host polymer and the diffusion profiles of the encapsulated drugs. In this review various mechanisms of controlled drug delivery using polymeric MNs, including new strategies, applications, and their future outlook are summarized and evaluated.

Preparation and in vitro release of dual-drug resinate complexes containing codeine and chlorpheniramine.

OBJECTIVE: To develop the dual-drug resinate complexes containing codeine and chlorpheniramine with a novel batch processing, characterize the dual-drug resinate complexes, and study its drug release behavior in vitro. METHODS: A procedure of simultaneous dual-drug loading using combination solutions composed of different proportions of codeine phosphate and chlorpheniramine maleate was performed to achieve the specific resinate, and the dual-drug loading content was determined by high-performance liquid chromatography method. The dual-drug resinate complexes were characterized by a scanning electron microscope, and the formation mechanisms were confirmed with X-ray diffraction analyses and differential scanning calorimetric analyses. The release behavior of the two drugs from the dual-drug resinate complexes in vitro was studied in the media simulating in vivo environments (simulated gastric fluid: pH = 1.2 HCl, simulated in vivo ionic strength: 0.15 M NaCl, and simulated intestinal fluid: pH = 6.8 buffer solution containing KH2PO4-NaOH). RESULTS: Scanning electron microscopic analyses proved that the dual-drug resinate complexes had the same appearance and characters as the initiative ion exchange resins (IERs). Via X-ray diffraction and differential scanning calorimetric analyses, it is found that the two drugs in dual-drug resinate complexes were combined with IERs by chemical bond. The drug-resinate complex, like IER, was in amorphous state. More than 90% of codeine phosphate was released in 15 minutes in three different media, whereas little amount of chlorpheniramine maleate was released in all the release time in the medium pH = 1.2 HCl, and the release equilibrium time was about 5 minutes, only 40% was released in the medium 0.15 M NaCl, and the equilibrium time was 40 minutes, and about 90% was released in the medium pH = 6.8 KH2PO4-NaOH. The increased ionic strength generally accelerated the release of the two drugs from the dual-drug resinate complexes. CONCLUSION: The dual-drug resinate complexes were formed through the reaction between the drugs and the IERs by chemical bond. The release behavior of the drug from the dual-drug resinate complexes in vitro was mainly correlated with the drug molecular structure, the eluting ionic strength, composition, and ionic strength of the release media. The novel dual-drug resinate complexes could be used to deliver two drugs in one therapeutic dose.