Aspirin is apt to hydrolyze. In order to improve its stability, a new method has been developed involving the application of hot-melt sub-and outercoating combined with enteric aqueous coating. The main aim was to inv...Aspirin is apt to hydrolyze. In order to improve its stability, a new method has been developed involving the application of hot-melt sub-and outercoating combined with enteric aqueous coating. The main aim was to investigate the influence of these factors on the stability of ASA and understand how they work. Satisfactory storage stability were obtained when the aspirin tablet core coated with Eudragit L30D55 film was combined with glycerin monostearate(GMS) as an outercoat. Hygroscopicity testing indicated that the moisture penetrating into the tablet may result in a significant change in the physical properties of the coating film observed by scanning electron microscopy. Investigation of the compatibility between the drug and film excipients shows that the talc and methacrylic acid had a significant catalytic effect on ASA. A hypothesis was proposed that the hydrolysis of ASA enteric coated tablets(ASA-ECT) was mostly concentrated in the internal film and the interfaces between the film and tablet core. In conclusion, hot-melt coating technology is an alternative to subcoating or outercoating. Also, GMS sub-coating was a better choice for forming a stable barrier between the tablet core and the polymer coating layer, and increases the structure and chemical stability.展开更多
Molecular recognition in water is the basis of numerous biological functions.The key for efficient and selective recognition of an organic drug molecule is to bind both its polar and nonpolar groups.This is achieved b...Molecular recognition in water is the basis of numerous biological functions.The key for efficient and selective recognition of an organic drug molecule is to bind both its polar and nonpolar groups.This is achieved by bioreceptors for which specific noncovalent interactions are efficiently used in a hydrophobic pocket.In contrast,most synthetic receptors cannot efficiently bind the neutral,polar groups of drug molecules and,thus,often exhibit poor binding selectivity and affinity.In this research,we report a systematic study on the binding behaviors of three types of macrocyclic hosts(amide naphthotubes,cucurbit[7]uril,andβ-cyclodextrin)to 18 model compounds and 13 drug molecules.Our results show that the high desolvation penalty of polar groups of guests is the reason for the relatively low binding affinity of cucurbit[7]uril andβ-cyclodextrin.However,amide naphthotubes with a biomimetic cavity bind efficiently and selectively to organic guests through hydrophobic effects and hydrogen bonding.Drug molecules with multiple polar groups can be better accommodated by these naphthotubes.The anti-configured naphthotube show good biocompatibility according to preliminary cell experiments and is capable of enhancing the water solubility of two poorly soluble drug molecules.Therefore,they may have practical applications in pharmaceutical sciences.展开更多
基金supported by the National Natural Science Foundation of China(No.81402858)the Liaoning Natural Science Foundation(No.2015020736)Shenyang Pharmaceutical University Long-term Training Fund(No.ZCJJ2014406)
文摘Aspirin is apt to hydrolyze. In order to improve its stability, a new method has been developed involving the application of hot-melt sub-and outercoating combined with enteric aqueous coating. The main aim was to investigate the influence of these factors on the stability of ASA and understand how they work. Satisfactory storage stability were obtained when the aspirin tablet core coated with Eudragit L30D55 film was combined with glycerin monostearate(GMS) as an outercoat. Hygroscopicity testing indicated that the moisture penetrating into the tablet may result in a significant change in the physical properties of the coating film observed by scanning electron microscopy. Investigation of the compatibility between the drug and film excipients shows that the talc and methacrylic acid had a significant catalytic effect on ASA. A hypothesis was proposed that the hydrolysis of ASA enteric coated tablets(ASA-ECT) was mostly concentrated in the internal film and the interfaces between the film and tablet core. In conclusion, hot-melt coating technology is an alternative to subcoating or outercoating. Also, GMS sub-coating was a better choice for forming a stable barrier between the tablet core and the polymer coating layer, and increases the structure and chemical stability.
基金This research was financially supported by the National Natural Science Foundation of China(nos.21772083 and 21822104)the Shenzhen Special Funds(KQJSCX20170728162528382 and JCYJ20180504165810828)+3 种基金the Guangdong Provincial Key Laboratory of Catalysis(2020B121201002)the China Postdoctoral Science Foundation(grant no.2019M652183)the University of Macao(MYRG2019-00059-ICMS)the Shenzhen Nobel Prize Scientists Laboratory Project(C17213101)。
文摘Molecular recognition in water is the basis of numerous biological functions.The key for efficient and selective recognition of an organic drug molecule is to bind both its polar and nonpolar groups.This is achieved by bioreceptors for which specific noncovalent interactions are efficiently used in a hydrophobic pocket.In contrast,most synthetic receptors cannot efficiently bind the neutral,polar groups of drug molecules and,thus,often exhibit poor binding selectivity and affinity.In this research,we report a systematic study on the binding behaviors of three types of macrocyclic hosts(amide naphthotubes,cucurbit[7]uril,andβ-cyclodextrin)to 18 model compounds and 13 drug molecules.Our results show that the high desolvation penalty of polar groups of guests is the reason for the relatively low binding affinity of cucurbit[7]uril andβ-cyclodextrin.However,amide naphthotubes with a biomimetic cavity bind efficiently and selectively to organic guests through hydrophobic effects and hydrogen bonding.Drug molecules with multiple polar groups can be better accommodated by these naphthotubes.The anti-configured naphthotube show good biocompatibility according to preliminary cell experiments and is capable of enhancing the water solubility of two poorly soluble drug molecules.Therefore,they may have practical applications in pharmaceutical sciences.
