ABSTRACT
Objective: To optimize the inclusion process of decomposed volatile oil from Atractylodes macrocephala (DVOA) with hydroxypropyl-β-cyclodextrin (HP-β-CD). Methods: The inclusion complex was prepared by the freeze drying method. The preparation process was evaluated using fluorescence spectrophotometry. The inclusion process conditions were screened by the orthogonal test, with the inclusion ratio and oil ratio as indexes, and mass ratio between HP-β-CD and DVOA, inclusion temperature and inclusion time as the impacting factors. The inclusion complex was characterized through ultraviolet-visible spectra (UV-vis), fluorescence spectra (FL) and microscopic imaging, and the stability test was performed. Simultaneously, the chemical composition in DVOA before and after inclusion was analyzed by GC-MS technique. Results: The DVOA and HP-β-CD had formed inclusion complex, the optimal inclusion conditions were as follows: The mass ratio of HP-β-CD to DVOA was 10:1, the inclusion temperature was 30℃, the inclusion time was 2.0 h, and the ratios of average inclusion and oil were 73.32% and 10.43%, respectively. The chemical composition of DVOA was consistent before and after inclusion, the inclusion just had the slight effects on proportion of each component. Conclusion: The preparation process of DVOA/HP-β-CD inclusion complex under the optimal conditions is reasonable, stable, and feasible, and can provide the reliable experimental basis for the anti-tumor new drug research and development of DVOA.
ABSTRACT
BackgroundStudies confirmed that ultraviolet A (UVA)- riboflavin photodynamic therapy can control keratoconus progresses by altering the physicochemical property of cornea.The collagen components of amniotic membrane transplantation is similar to that of cornea and amniotic membrane transplantation has been widely used to ocular surface reconstruction.However,the study on UVA riboflavin-induced-collagen crosslinking for amniotic tissue is less now.ObjectiveThis study was to investigate the role of UVA-riboflavin on frozen-preserved human amniotic membrane.Methods Human amnions were obtained in informed consent and prepared into 2 mm×15 mm pieces and were then divided into 4 groups using lottery method and 6 pieces for each group.The first 3 groups were treated with the photosensitizer riboflavin and UVA-irradiation ( wavelength:370 nm ; irradiation energy:1,2 or 3 mW/cm2,distance:10 mm) for 30 minutes,and the untreated fourth group was as control group.Biomechanical stress-strain test was performed using a microcomputer-controlled biomaterial tester and the stress(mN) was recorded when the strains were set to 5％,10％ and 15％.The 7 mm diameter of human amniotic membrane pieces were trephined and divided into 4 groups(5 pieces for each group) with the treated method as mentioned above,and then the buttons were exposed to 0.1％ collagenase Ⅰ solution.The transparency was scored and the complete dissolving time was record.In histological evaluation,three groups (3 pieces for each group) of human amniotic membranes were treated using UVAriboflavin(3 mW/cm2),0.1％riboflavin,normal saline for 30 minutes respectively and examined under the transmission electron microscopy.This study was performed under the permission of the Ethic Commission of Beijing Tongren Hospital.ResultsWhenthestrainwas 5％,10％,15％,thestressof controlgroupand1,2,3 mW/cm2UVA group were statistically signifcantly different ( F =3.411,P =0.037; F =9.927,P =0.001;F=11.118,P=0.000).The tensile strength of human amniotic membrane cross-linked with UVA-riboflavin was statistically significantly increased in comparison to the control group (P＜0.05 ),and the tensile strength of human amniotic membrane became stronger as UVA power increased.The complete dissolve time was (8.6± 1.8 ) hours for the control group,(39.6± 2.3 ) hours for 1 mW/cm2 UVA group,(71.4±0.9 ) hours for 2 mW/cm2 UVA group,(78.8± 1.8 ) hours for 3 mW/cm2 UVA group,showing the enhanced anti-enzyme ability of human amniotic membrane after cross-linking(P＜0.01 ).The collagen density in the UVA-riboflavin treated group was increased,the connection among the collagen fibers as well as between the stroma and the epithelium became tighter than those of control group.ConclusionsCollagen cross-linking with UVA-riboflavin make the biomechanical strength and enzymatic resistance of human amniotic membrane enhance and ultrastructure change of human amniotic membrane.