In-Process Control Testing

Molecularly Imprinted Polymers for Pharmaceutical Impurities: Design and Synthesis Methods

The safety of a medicinal product is determined by its pharmacological and toxicological profile, which depends not only on the active substance's toxicological properties, but also on the impurities it contains. Because impurities are a problem that must be considered to ensure the safety of a drug product, many studies have been conducted regarding the separation or purification of active pharmaceutical ingredients (APIs) and the determination of impurities in APIs and drug products. Several studies have applied molecularly imprinted polymers (MIPs) to separate impurities in active ingredients and as adsorbents in the sample preparation process. This review presents the design of MIPs and the methods used to synthesise MIPs to separate impurities in APIs and drug product samples, the application of MIPs to separate impurities, and a view of future studies involving MIPs to remove impurities from pharmaceutical products. Based on a comparison of the bulk and surface-imprinting polymerisation methods, the MIPs produced by the surface-imprinting polymerisation method have a higher adsorption capacity and faster adsorption kinetics than the MIPs produced by the bulk polymerisation method. However, the application of MIPs in the analysis of APIs and drug products are currently only related to organic compounds. Considering the advantages of MIPs to separate impurities, MIPs for other impurities still need to be developed, including multi-template MIPs for simultaneous separation of multiple impurities.

Genotoxic and chemopreventive potentials of ethanol leaves extract of Annona muricata on N-Ethyl-N-Nitrosourea-induced pro-leukaemia carcinogen in mice model by bone marrow micronucleus assay

Background. Studies have proven the effect of several agents, including natural products, to induce, prevent and treat genotoxicity through experimental models and clinical trials. In this study, the genotoxic preventive potential of Annona muricata ethanol extract on N-Ethyl-N-Nitrosourea (ENU)-induced pro-leukaemia in mice models using micronuclei formation in bone marrow was assessed. Materials and methods. Forty-eight mice weighing 18-24g were randomly divided into six groups of eight mice. The mice were intravenously administered 20mg/kg of NEU 48 hourly 3 times, 80mg/kg of NEU 48 hourly 3 times. The negative control was fed with feed and water only. We introduced 0.2ml (0.1g/ml) ethanolic extract of Annona muricata for 3 weeks prior to NEU low dosage administration, 0.2ml (0.1g/ml) ethanolic extract of Annona muricata for 3 weeks prior to ENU high dosage and Annona muricata (ethanolic extract) administration, and gave commercial diet to the adverse/ toxicity group.  The bone marrow was harvested, smeared and stained using MayGrumwald. The procedure enabled the determination of micronucleus polychromatic erythrocytes (MNPCEs) microscopically. Results. Groups exposed to various dosages of the ENU yielded significantly increased MNPCEs, with group B producing higher MNPCEs. The groups treated with the extract displayed a significant reduction in the MNPCEs despite prior exposure to concentrations of NEU. The adverse group displayed no difference in MNPCEs compared with the negative control. Conclusion. The ENU induced genotoxicity depending on its concentration. The extract displayed a profound capacity to prevent genotoxicity and alleviate leukaemia with good tolerance.

Synthetic Diphenylacetylene-Based Retinoids Induce DNA Damage in Chinese Hamster Ovary Cells without Altering Viability

All-trans-retinoic acid (ATRA), the active metabolite of vitamin A, plays a pivotal role in cell differentiation, proliferation and embryonic development. It is an effective therapy for dermatological disorders and malignancies. ATRA is prone to isomerization and oxidation, which can affect its activity and selectivity. Novel diphenylacetylene-based ATRA analogues with increased stability can help to overcome these problems and may offer significant potential as therapeutics for a variety of cancers and neurodegenerative diseases, including amyotrophic lateral sclerosis. Here, we investigated the effects of these retinoids on cell viability and genotoxicity in the widely used model system of the rapidly proliferating Chinese hamster ovary cell line. DC360 is a fluorescent ATRA analogue and DC324 is a non-active derivative of DC360. EC23, DC525, DC540, DC645, and DC712 are promising analogues with increased bioactivity. The cytotoxic activity of the compounds was evaluated by ATP assay and DNA damage was tested by comet assay. No cytotoxicity was observed in the 10⁻⁶–10⁻⁵ M concentration range. All compounds induced DNA migration similar to ATRA, but DC324, DC360 and EC23 did so to a greater extent, particularly at higher concentrations. We believe that retinoid receptor-independent genotoxicity is a general characteristic of these compounds; however, further studies are needed to identify the molecular mechanisms and understand their complex biological functions.

Implementation of at-line capillary zone electrophoresis for fast and reliable determination of adenovirus concentrations in vaccine manufacturing

A CZE method was validated and implemented for fast and accurate in-process determination of adenovirus concentrations of downstream process samples obtained during manufacturing of adenovirus vector-based vaccines. An analytical-quality-by-design approach was embraced for method development, method implementation, and method maintenance. CZE provided separation of adenovirus particles from sample matrix components, such as cell debris, residual DNA and proteins. The intermediate precision of the virus particle concentration was 6.9% RSD and the relative bias was 2.3%. In comparison, the CZE method is intended to replace a quantitative polymerase chain reaction method which requires three replicates in three analytical runs to achieve an intermediate precision of 8.1% RSD. Given that, in addition, the time from sampling till reporting results of the CZE method was less than 2 h, whereas quantitative polymerase chain reaction requires 3 days, it follows that the CZE method enables faster processing times in downstream processing.