[Definitive screening design combined with design space for optimizing purification process of Scutellariae Radix extract].

In the pharmacopoeia, many process parameters for the purification process of Scutellariae Radix are unclear. In this study, deterministic screening design combined with design space method was used to optimize the purification process of Scutellariae Radix extract. Nine method parameters such as mass fraction of solution(X_1), first acid precipitation pH(X_2) and first holding time(X_3) in the purification process were firstly studied by definitive screening design. The yield of baicalin was defined as the evaluation index. A stepwise regression method was used then to build quantitative models between evaluation index and method parameters and the three most critical impact parameters were determined. Probability-based design space was calculated and successfully verified with the experimental error simulation method. Finally, the second standing temperature, the first standing temperature and the pH value of the second acid precipitation were determined as the three most critical method parameters. The recommended operating space was as follows: the second standing temperature 5-7 ℃, the first standing temperature 13-15 ℃, and the pH of the second acid precipitation 1.5-1.7. Within this operating space, the baicalin yield in the purification process was over 80%, and the probability of reaching the standard was over 0.96. In this study, we optimized the effect of various parameters for the purification process of the Scutellariae Radix extract in the pharmacopoeia on the yield of baicalin and provided a reference for industrial production of the exact of Scutellariae Radix.

[Research progress on percolation extraction process of traditional Chinese medicines].

Percolation extraction is a conventional extraction method used in the processing of traditional Chinese medicines. After medicinal material powder is placed in a percolation tank, the extraction solvent is continuously added, and percolation extract is collected simultaneously. The percolation equipment is simple. The percolation operation is easy. It is applicable to a wide range of medicinal materials. Components that are unstable under thermal conditions can be effectively extracted. However, there are also disadvantages, such as high solvent consumption, long extraction time, and high energy consumption in subsequent concentration processes. This article mainly reviews the research progress on the common equipment types, affecting factors, parameter optimization methods, and process monitoring. According to analysis on literatures, solvent composition, impregnation time, percolation speed, and solvent consumption are considered as the important factors of percolation processes. At present, near-infrared spectroscopy is widely used in the monitoring of percolation process, and partial least square is a commonly used quantitative modeling method. According to the concept of "Quality by Design", in-depth investigation of the percolation process mechanism and development of process control methods are future development trends. Therefore, process modeling, process optimization and process monitoring shall be improved. The mechanism models and the empirical models of column chromatography can be used as references to construct the percolation process models. The effect of the quality changes of medicinal materials shall be taken into account when optimizing the percolation process parameters. More simple and easy methods shall be developed to monitor the percolation process status and key properties of percolation extracts.

Critical pharmaceutical process identification considering chemical composition, biological activity, and batch-to-batch consistency: A case study of notoginseng total saponins.

Objective: Critical pharmaceutical process identification (CPPI) is an important step in the implementation of quality by design concept to traditional Chinese medicines (TCMs). Risk assessment methods are usually used in CPPI. However, risk evaluation is usually subjective. The purpose of this work is to present a more objective CPPI method. Methods: A CPPI method considering chemical composition, biological activity, and batch-to-batch consistency was presented in this work. The manufacturing process of notoginseng total saponins (NTS) was investigated as an example. The changes of chemical composition, biological activity, and chemical composition consistency after main processes were measured and compared. A significant change of them indicated a critical process. Results: After extraction process and chromatography process, saponin purity and chemical composition similarity remarkably increased, and saponin content variations decreased. Thrombin inhibitory activity was remarkably decreased after chromatography process. Because of the large influences on NTS quality, extraction process and chromatography process were identified to be critical processes of NTS. Conclusion: Based on a comprehensive and objective examination of the role of each process, critical pharmaceutical processes can be identified. A similar method can also be applied to other TCM processes.

Critical process parameter identification of manufacturing processes of Astragali Radix extract with a weighted determination coefficient method.

Objective: Critical process parameters (CPPs) identification is an important step of the implementation of quality by design (QbD) concept. There are many CPP identification methods, such as risk analysis method, sensitivity analysis method, multiple linear regression method, standard partial regression coefficient (SPRC) method, and so on. The SPRC method can consider multiple process critical quality attributes (CQAs) simultaneously, but the determination of CPP number is subjective. Therefore, new CPP identification method is still required. Methods: The manufacturing process of Astragali Radix extract, which contained water reflux extraction, concentration, and ethanol precipitation, was used as an example. First, the multiple process CQAs were determined to be the yield of pigment, dry matter, sugars, and active ingredients. Second, the potential CPPs were determined by a knowledge organization method. Plackett-Burman designed experiments were then performed. A weighted determination coefficient ( R w 2 ) method was presented to identify CPPs. In this method, the importance of different CQAs was considered. Process parameters were removed one-by-one according to their importance index. The decrease in R w 2 was used to characterize the importance of the removed parameter. If the decrease of R w 2 was less than a preset threshold, the removed parameter was not a CPP. Results: During the manufacturing process of Astragali Radix extract, the potential CPPs determined by the knowledge organization method were water consumption, reflux extraction time, extraction frequency, ethanol content, ethanol consumption, and concentration endpoint. Reflux extraction time, the first ethanol consumption, the second ethanol consumption, and the second ethanol precipitation refrigeration temperature were found to be CPPs using the weighted determination coefficient method with the threshold of 10%. Conclusion: Using the weighted determination coefficient method, CPPs can be determined with all the CQAs considered based on their importance. The determination of CPP number is more objective compared with the SPRC method.

[Quantitative chromatographic fingerprint analysis of Sanye Tangzhiqing Decoction based on quality by design concept].

In this work,a high performance liquid chromatography-ultraviolet( HPLC-UV) detection technology was used to establish fingerprint analysis method for Sanye Tangzhiqing Decoction following an analytical quality by design( AQb D) approach. Firstly,column temperature,flow rate,and gradient elution conditions were determined as the method parameters needing to be optimized. Then according to the results of definitive screening design,three critical method attributes( CMAs) were identified,including peak number,the percentage of common peak area to total peak area,and retention time of the last peak. A stepwise regression method was used then to build quantitative models between CMAs and method parameters. Probability-based design space was calculated and successfully verified using the experimental error simulation method. After the analysis conditions were optimized,the contents of six components,namely chlorogenic acid,paeoniflorin,rutin,hyperoside,quercetin-3-O-ß-D-glucuronide,and salvianolic acid B were simultaneously determined. There were 19 common peaks in the fingerprint and their common peak area accounted for 96% of the total peak area. Both fingerprint and quantitative analysis methods were validated applicable in methodology study,and they can be applied to determine new samples.

[Research on quality standards of standard decoction of Fructus Corni piece].

This study aims to develop the quality standards of Fructus Corni piece standard decoction. Morroniside and loganin were considered as index components. The content determination method of morroniside and loganin were developed. The fingerprint analysis method was also established. The standard decoctions of 15 batches of Fructus Corni pieces from Henan, Zhejiang, and Shaanxi were analyzed. The similarity values of fingerprint were all above 0.99. The transfer rates of morroniside were all higher than 100%. The quality evaluation indices of standard decoction were discussed. The transfer rate of an index component was not easy to be measured accurately and its concept was not rigorous. Therefore, index component yield was suggested as an evaluation index of standard decoction. Two methods for setting quality standards of standard decoctions, which were the ■ method and the ■ method, were compared. It was found that the standard range of ■ method was wider and more suitable for smaller sample size of standard decoction. The quality standards of Fructus Corni standard decoction were as follows, dry matter extraction ratio 37.48%-69.60%; morroniside yield 8.719-16.19 mg·g~(-1) piece; loganin yield 4.342-8.064 mg·g~(-1) piece.

[Quantitative analysis method of Shengxuebao Mixture by HPLC-UV-MS based on quality by design concept].

In this study, the HPLC-UV-MS method for the simultaneous determination of eight active ingredients of Shengxuebao Mixture were developed based on the concept of quality by design（QbD）with a stepwise optimization approach. After the analytical target profile（ATP）had been defined, albiflorin, paeoniflorin, 2, 3, 5, 4'-tetra-hydroxy-stilbene-2-O-ß-D-glucopyranoside, specnuezhenide, ecliptasaponin D, emodin, calycosin-7-glucoside, and astragaloside Ⅳ were identified as the indicator components. The resolution and the signal-to-noise ratio of indicator components were then selected as critical method attributes (CMA) for the first step optimization. According to the results collected from fractional factorial design, critical method parameters (CMP) were determined with a multiple linear regression method, which included the amount of acid addition in the mobile phase, temperature, gradient, and wavelength. After that, the amount of acid addition and the wavelength were optimized to improve the resolution and the signal-to-noise ratio of the indicator components. The peak symmetry factors of specnuezhenide and emodin were then set as CMA for the second step optimization. The Box-Behnken designed experiments were conducted. The temperature and gradient were optimized after modelling. The design space were calculated and verified. The optimized analytical method was validated, and the results showed a good precision, accuracy and stability, which means that it can be used for the quantification of the indicator components in Shengxuebao Mixture.

[Comparison of two algorithms for development of design space-overlapping method and probability-based method].

In this work, two algorithms (overlapping method and the probability-based method) for design space calculation were compared by using the data collected from extraction process of Codonopsis Radix as an example. In the probability-based method, experimental error was simulated to calculate the probability of reaching the standard. The effects of several parameters on the calculated design space were studied, including simulation number, step length, and the acceptable probability threshold. For the extraction process of Codonopsis Radix, 10 000 times of simulation and 0.02 for the calculation step length can lead to a satisfactory design space. In general, the overlapping method is easy to understand, and can be realized by several kinds of commercial software without coding programs, but the reliability of the process evaluation indexes when operating in the design space is not indicated. Probability-based method is complex in calculation, but can provide the reliability to ensure that the process indexes can reach the standard within the acceptable probability threshold. In addition, there is no probability mutation in the edge of design space by probability-based method. Therefore, probability-based method is recommended for design space calculation.

[Detection of antioxidant activity of Danhong injection and its intermediate with a paper-based analytical device].

The paper-based analytical device (PAD) was applied in this study to analyze the antioxidant activity of Danhong injection and its intermediates. First polycaprolactone was printed on the surface of a filter paper with a 3D printing device. The modified filter paper was then prepared using polycaprolactone and solid paraffin as the modifiers. The PAD was prepared after adding DPPH ethanol solution to the modified filter paper. Ascorbic acid solutions with different concentrations were used as the positive drug on PAD. After the occurrence of color reactions, the PAD was dried, and the data of color were collected by a cell phone. The color component G and grayscale were selected as the potential indices for measurement according to the values of determination coefficients, detection limits, and effective number of digits. Qualitative and quantitative analysis of Danhong injection and the concentrate of aqueous extract were realized with the PAD. Because no significant differences were observed between the results obtained using the two potential indices, the average values of these two were used for analysis, and the antioxidant activity of Danhong injection and the concentrate of aqueous extract was equivalent to ascorbic acid solutions of 3.7, 46 g·L⁻¹, respectively. The PAD method presented in this work can be a simple method to determine biological activities of Chinese medicines and their intermediates.

[Research advances in secondary development of Chinese patent medicines based on quality by design concept].

Quality by design (QbD) concept is an advanced pharmaceutical quality control concept. The application of QbD concept in the research and development of pharmaceutical processes of traditional Chinese medicines (TCM) mainly contains five parts, including the definition of critical processes and their evaluation criteria, the determination of critical process parameters and critical material attributes, the establishment of quantitative models, the development of design space, as well as the application and continuous improvement of control strategy. In this work, recent research advances in QbD concept implementation methods in the secondary development of Chinese patent medicines were reviewed, and five promising fields of the implementation of QbD concept were pointed out, including the research and development of TCM new drugs and Chinese medicine granules for formulation, modeling of pharmaceutical processes, development of control strategy based on industrial big data, strengthening the research of process amplification rules, and the development of new pharmaceutical equipment..

[Optimization of ethanol reflux extraction process of red ginseng using a design space approach based on hazard and operability analysis].

Quality by design principle was used as a guideline in this study to optimize ethanol reflux extraction of red ginseng. Firstly, hazard and operability analysis(HAZOP) was used as a risk assessment tool to evaluate the hazard degree of process parameters.Ethanol concentration, the ratio of alcohol and herbal material (A/M ratio), and extraction time were identified as the critical process parameters(CPPs) according to HAZOP method.Secondly, Box-Behnken experimental design was applied to establish theregression models between CPPs and the process indices. Finally, the design space was calculated. The recommended operation space of parametersis as follows：alcohol concentration of 90.3%-90.7%, A/M ratio of 2.5-3.1 mL•g ⁻¹ and extraction time of 124-130 min. The study shows that the design space approach combined with the risk assessment using HAZOP has the potential to reduce the risk of red ginseng extraction process, which might ultimately improve the process control..

[Optimization of lime milk precipitation process of Lonicera Japonica aqueous extract based on quality by design concept].

Design space approach was applied in this study to optimize the lime milk precipitation process of Lonicera Japonica (Jinyinhua) aqueous extract. The evaluation indices for this process were total organic acid purity and amounts of 6 organic acids obtained from per unit mass of medicinal materials. Four critical process parameters (CPPs) including drop speed of lime milk, pH value after adding lime milk, settling time and settling temperature were identified by using the weighted standardized partial regression coefficient method. Quantitative models between process evaluation indices and CPPs were established by a stepwise regression analysis. A design space was calculated by a Monte-Carlo simulation method, and then verified. The verification test results showed that the operation within the design space can guarantee the stability of the lime milk precipitation process. The recommended normal operation space is as follows： drop speed of lime milk of 1.00-1.25 mL•min⁻¹, pH value of 11.5-11.7, settling time of 1.0-1.2 h, and settling temperature of 10-20 ℃..

[Optimize dropping process of Ginkgo biloba dropping pills by using design space approach].

In this paper, a design space approach was applied to optimize the dropping process of Ginkgo biloba dropping pills. Firstly, potential critical process parameters and potential process critical quality attributes were determined through literature research and pre-experiments. Secondly, experiments were carried out according to Box-Behnken design. Then the critical process parameters and critical quality attributes were determined based on the experimental results. Thirdly, second-order polynomial models were used to describe the quantitative relationships between critical process parameters and critical quality attributes. Finally, a probability-based design space was calculated and verified. The verification results showed that efficient production of Ginkgo biloba dropping pills can be guaranteed by operating within the design space parameters. The recommended operation ranges for the critical dropping process parameters of Ginkgo biloba dropping pills were as follows: dropping distance of 5.5-6.7 cm, and dropping speed of 59-60 drops per minute, providing a reference for industrial production of Ginkgo biloba dropping pills.

[Application of continuous mixing technology in ethanol precipitation process of Salvia miltiorrhiza by using micromixer].

Continuous pharmaceutical manufacturing is one of the development directions in international pharmaceutical technology. In this study, a continuous mixing technology of ethanol and concentrated extract in the ethanol precipitation of Salvia miltiorrhiza was realized by using a membrane dispersion method. The effects of ethanol flowrate, concentrated extract flowrate, and flowrate ratio on ethanol precipitation results were investigated. With the increase of the flowrates of ethanol and concentrated extract, retention rate of active phenolic acids components was increased, and the total solid removal rate was decreased. The purity of active components in supernatants was mainly affected by the ratio of ethanol flowrate and concentrated extract flowrate. The mixing efficiency of adding ethanol under continuous flow mixing mode in this study was comparable to that of industrial ethanol precipitation. Continuous adding ethanol by using a membrane dispersion mixer is a promising technology with many advantages such as easy enlargement, large production per unit volume, and easy control.

[Design space approach to optimize first ethanol precipitation process of Dangshen].

Design space approach is applied in this study to enhance the robustness of first ethanol precipitation process of Codonopsis Radix (Dangshen) by optimizing parameters. Total flavonoid recovery, dry matter removal, and pigment removal were defined as the process critical quality attributes (CQAs). Plackett-Burman designed experiments were carried out to find the critical process parameters (CPPs). Dry matter content of concentrated extract (DMCE), mass ratio of ethanol to concentrated extract (E/C ratio) and concentration of ethanol (CEA) were identified as the CPPs. Box-Behnken designed experiments were performed to establish the quantitative models between CPPs and CQAs. Probability based design space was obtained and verified using Monte-Carlo simulation method. According to the verification results, the robustness of first ethanol precipitation process of Dangshen can be guaranteed by operating within the design space parameters. Recommended normal operation space are as follows: dry matter content of concentrated extract of 45.0% - 48.0%, E/C ratio of 2.48-2.80 g x g(-1), and the concentration of ethanol of 92.0% - 92.7%.

[Simultaneous determination of danshensu, hydroxysafflor yellow A, rosmarinic acid, lithospermic acid, salvianolic acid B in water extract of mixed salviae miltiorrhizae radix et rhizoma and carthami flos by HPLC].

OBJECTIVE: To develop an HPLC method to determine the contents of danshensu, hydroxysafflor yellow A, rosmarinic acid, lithospermic acid, salvianolic acid B in the water extract of mixed Salviae Miltiorrhizae Radix et Rhizoma and Carthami Flos simultaneously. METHOD: The separation were carried out at 30 degrees C on a ZORBAX Eclipse Plus C18 column (4.6 mm x 100 mm, 1.8 microm) with formic acid-500 mmol x L(-1) ammonium formate-water solution (0.5:10:90) as mobile phase A and acetonitrile-formic acid solution (100: 0.5) as mobile phase B in gradient mode at a flow rate of 0.5 mL x min(-1). Detection wavelengths were 280 nm for danshensu, rosmarinic acid, lithospermic acid, salvianolic acid B, and 380 nm for hydroxysafflor yellow A. RESULT: The 5 components were separated well with a good linearity (R2 > 0.999 3) in the range of the test concentration. The average recoveries of danshensu, hydroxysafflor yellow A, rosmarinic acid, lithospermic acid, and salvianolic acid B were 99.1%, 102%, 102%, 98.5% and 101%, respectively. CONCLUSION: This method is simple, accurate, and repeatable.