As an emerging precision particle manufacturing technology, microfluidic technology harnesses the unique microfluidic phenomena in microscale environments to achieve continuous and reproducible production of micro/ nanoparticles. This review systematically summarizes the structural design principles and operational characteristics of common microfluidic channels, elaborates on recent advances in particle-based drug delivery systems, and highlights its advantages in controlling particle size, manipulating structures, and enhancing process efficiency. Furthermore, this review explores industrialization strategies, technical challenges, and future development directions of microfluidic technology, aiming to serve as a reference for the efficient preparation of micro/nanoparticle-based drug delivery systems.

In biological preparations, parameters such as particle size, shape, and aggregation state can reflect drug stability and serve as critical indicators for safety assessment and immunogenicity prediction. There are various methods for determining particle size and size distribution, among which light scattering method stands out as a rapid, noninvasive, and highly sensitive technique with broad application potential. Its advantages include no requirement for sample dilution, simultaneous measurement of multiple parameters(e.g., size, morphology, and aggregation state of proteins). This technology can make significant contributions to protein solution analysis, drug quality control, optimization of production processes, and drug development. This review summarizes particle size measurement methods, current applications of mainstream light scattering instruments, and how these instruments achieve measurement requirements of biomedical materials and preparations, offering calibration strategies for practical measurements to enhance measurement accuracy for biomedical materials and preparations.

In the research, biphenyl(2) was used as starting material to synthesize 4,4'-bis(2-bromoacetyl)-1,1'- biphenyl(3) with high yield. Then, 4,4'-bis[N-tert-butoxycarbonyl-(2S)-pyrrolidine-2-carbonyloxymethylformyl]-1,1'- biphenyl(5) was synthesized via esterification between 3 and N-tert-butoxycarbonyl-L-proline(4). 4,4'-Bis[2-[N-tertbutoxycarbonyl-(2S)-pyrrolidine-2-yl]-1H-imidazol-5-yl]-1,1'-biphenyl(6) was prepared by ammonolysis and cyclization of 5. Compound 6 was deprotected by hydrochloric acid to give 4,4'-bis[2-[(2S)-pyrrolidine-2-yl]-1H-imidazol-5-yl]-1,1'- biphenyl tetrahydrochloride(7), which was followed by condensation with N-(methoxycarbonyl)-L-valine(8) to give the N,N'-[(1,1'-biphenyl)-4,4'-diylbis[1H-imidazole-5,2-diyl-(2S)-2,1-pyrrolidinediyl[(1S)-1-(1-methylethyl)-2-oxo-2,1- ethanediyl]]]biscarbamic acid C,C'-dimethyl ester(9), and 9 went through salt formation with HCl to provide daclatasvir dihydrochloride(1). The total mole yield was 38.5％ and purity was 99.75％ . The improved process has low cost and mild reaction condition, which is very suitable for industrial production.

A synthetic process of mivacurium chloride(1) was optimized. 3,4,5-Trimethoxyphenylacetic acid(7) and 3,4-dimethoxyphenylethylamine were used as starting materials to obtain the key intermediate (R)-5'- methoxylabdanin[(R)-2] dibenzoyl tartrate through dehydration condensation, intramolecular cyclization, imine reduction, reductive amination, and chiral resolution. Compound (R)-2 dibenzoyl tartrate reacted with 1,3-propylene glycol cyclic sulfate under alkaline conditions via nucleophilic substitution and hydrolysis to obtain its quaternary ammonium alcohol(3). Finally, compound 3 was condensed with trans-4-octene-1,8-dicarboxylic acid to obtain 1. In the post-treatment of the intramolecular cyclization step, omission of alkaline solution for quenching phosphorus oxychloride effectively prevented the formation of oxidative impurities. The synthesis of (R)-2 dibenzoyl tartrate was improved by reducing two resolutions to a single step, increasing the resolution yield from 33％ to 42％ . Replacing 3-chloropropanol with 1,3-propylene glycol cyclic sulfate during the synthesis of compound 3 eliminated polymer impurity A and simplified the process by omitting column chromatography. The optimized process achieved a total yield of 17.0％ (based on 7), and a purity of 99.6％ . It was verified by kilogram-level amplification and was suitable for industrial production.

Herein two related substances(A and B) of voclosporin(1) were prepared and purified. Compound B was Z-isomer of 1, named cyclo-[[(6Z)-(2S,3R,4R)-3-hydroxy-4-methyl-2-(methylamino)-6,8-nonadienoyl]-L-2- aminobutyryl-N-methyl-glycyl-N-methyl-L-leucyl-L-valyl-N-methyl-L-leucyl-L-alanyl-D-alanyl-N-methyl-L-leucyl-Nmethyl-L-leucyl-N-methyl-L-valyl]. E configuration of acetylated voclosporin(5) was transferred into related substance B via configuration conversion and acetyl group removal under triethylamine/lithium bromide with high-purity, which was reported at the first time. In addition, in the process optimization of 1, the over-oxidized impurity, related substance A was found and prepared for the first time. Its structure was confirmed as acetylated cyclosporine A acid by high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. The above two compounds can be served as the references for the quality control of 1.

Oral urate oxidase promotes intestinal uric acid excretion for gout treatment. To enhance the adhesion and uric acid degradation efficiency of recombinant pig-baboon chimeric urate oxidase(PBC) in the intestine, this study fused the mucin-binding protein(MUB) fragments with PBC to construct fusion proteins N1 to N7. By comparing the effects of different MUB fragments on the mucin-binding activity of PBC, and further investigating the high-density fermentation, separation, purification, and enzymatic properties of N5, it was found that the mucin-binding activity of fusion proteins N1 to N7 was significantly improved. Among them, the fusion protein N5, which linked the MUB fragment RⅣ at the N-terminus, showed a nearly 41-fold increase in mucin-binding activity. Using high-density fermentation, ammonium sulfate precipitation, polyethyleneimine clarification, and anion exchange chromatography, the purity of N5 reached 98.7％ , with a fermentation yield of 4.47 g/L. Additionally, the specific activity of N5(0.52 IU/mg) increased by 30％ compared to PBC, with enhanced substrate affinity(Km=14.29 μmol/L), and it remained stable under room temperature, alkaline conditions, and in the presence of common metal ions. This study provides a reference for the subsequent development of oral urate oxidase as a candidate drug.

This study screened small molecule compounds capable of specifically binding to and stabilizing the G-quadruplex(G4) structure within the Rv0341 gene of Mycobacterium tuberculosis. Firstly, circular dichroism(CD) spectroscopy was used to confirm the formation of the G4 structure(designated Rv0341G4) by the G-rich oligonucleotide sequence in Rv0341 gene. Subsequently, real time fluorescent quantitative reverse transcription polymerase chain reaction(qRT-PCR) and Western blot were employed to validate the inhibitory effects of candidate small molecules on Rv0341 expression. Through surface plasmon resonance(SPR) screening, a small molecule compound T-007 exhibiting high-affinity binding to Rv0341G4 was identified. Both qRT-PCR and Western blot analyses demonstrated that T-007 stabilizes the Rv0341G4 structure and downregulates Rv0341 transcription. This study provides valuable insights for developing novel anti-tuberculosis therapeutics targeting G4 structures.

This study developed transferrin-PEGylated docetaxel albumin nanoparticles(Tf-PEG-DANPs)-loaded lipid microbubbles and characterized their properties. Combined with ultrasound-targeted microbubble destruction(UTMD) technology, the drug targeting ability, therapeutic efficacy, toxicity, and adverse effects were systematically investigated through in vitro cellular experiments and in vivo animal models. The results demonstrated that Tf-PEG-DANPs-loaded lipid microbubbles exhibited a particle size of (152.11±16.28)nm with a ζ potential of (–6.24±2.35)mV, and displayed uniform quasi-spherical morphology. The encapsulation efficiency and drug loading were (94.61±0.67) ％ and (8.82±0.92) ％ , respectively. Compared with the conventional formulations, the Tf-PEG-DANPs-loaded lipid microbubbles combined with UTMD significantly inhibited proliferation and induced apoptosis in mouse 4T1 breast cancer cells. Furthermore, in vivo pharmacodynamic evaluationsshowed enhanced tumor suppression efficacy without inducing hepatic or renal toxicity in murine models. This research provided a novel targeted therapeutic strategy with high efficacy and low systemic toxicity, demonstrating substantial clinical potential for breast cancer treatment.

Based on the concept of quality by design, using the commercially available formulation Linzess® as the reference preparation, Box-Behnken design-response surface methodology was used to optimize the formulation of linaclotide capsules with the dissolution rate at 10 min as the evaluation index. The optimized formulation was as follows: selecting microcrystalline cellulose pellet core CP-305(with a particle size of approximately 400 μm), the amount of adhesive HPMC at 0.8％ (0.96 mg per capsule), and the ratio of calcium chloride to leucine of 3 ∶ 1(respectively 1.8 mg and 0.6 mg per capsule). Three batches of self-made preparations were prepared according to above final formulation for validation. The results showed that the content and content uniformity met the requirements. In various pH media, the dissolution rate of three batches of self-made capsules exceeded 85％ at 10 min, demonstrating consistent quality with the reference preparation.

The in vitro dissolution behavior of nitrendipine(1) tablets produced by seven different companies and the reference formulation(Bayotensin® mite) was investigated. According to the dissolution test conditions of the Japanese Pharmacopoeia(JP18), an ultra-high performance liquid chromatography(UPLC) method was established to determine the dissolution of 1 tablets. The paddle method was used, with a speed of 100 r/min, and 900 mL of 1.5 g/L polysorbate 80 solution as the dissolution medium. The similarity factor(f2) method and the dissolution curve similarity parameter(AV value) method were used to compared the differences in dissolution behavior between 1 tablets from seven companies and the reference formulation. The results showed that there were significant differences in the dissolution curves of 1 tablets from six companies and the reference formulation, whereas the sample from E company exhibited similarity(f2=57.5, AV=13.4). In addition, a physiologically based pharmacokinetic(PBPK) model for 1 tablets was established using GastroPlusTM software, and the method for predicting the dissolution rate of JP18 showed good in vitro and in vivo correlation. Substituting the in vitro dissolution curve for virtual bioequivalence simulation, the bioequivalence prediction results were basically consistent with the similarity results of the dissolution curve, which provided a reference for the development and screening of the prescription for 1 tablets.

The HPLC fingerprints of Epimedium and Epimedii Wushanensis Folium were established, and quality evaluation was carried out by combining similarity analysis, chemometric methods, and grey relational analysis. Separation was performed on a Welch Xtimate® C18 column with gradient elution(0.1％ of formic acid as mobile phase A, and acetonitrile as mobile phase B) at a flow rate of 1.0 mL/min, the column temperature of 30℃ , and detection wavelength of 270 nm. The HPLC fingerprints of five types of Epimedium were established. Quality evaluation was conducted through similarity analysis, principal component analysis(PCA), partial least squares discriminant analysis(PLS-DA), and grey relational analysis. The results showed that high similarity in fingerprints of the same origin and good specificity of the established fingerprints. The results of PCA and PLS-DA showed that there were significant differences in chemical composition among different origins. Grey relational analysis identified Longnan City(Gansu Province) and Tonghua City(Jilin Province) as the the optimal production areas for E.brevicornu Maxim. and E. koreanum Nakai, respectively, among the tested samples. The integrated method combining fingerprinting, chemometrics and grey relational analysis provided an effective means for the quality evaluation of Epimedii Folium from different origins.

The solid-liquid ratio and ethanol volume fraction for extraction of total alkaloids from Chelidonium were optimized by uniform design method with total alkaloid content as evaluation index. The purification process was further established via macroporous adsorption resin method by adjusting the diameter-to-height ratio, sample concentration, and eluent volume. The optimal extraction process parameters of total alkaloids from Chelidonium were as follows: solid-liquid ratio of 1∶30, 95％ ethanol, 3 cycles(1.7 h each). The optimal purification process was as follows: using X-5 macroporous adsorption resin, mass concentration of sample liquid of 0.20 g/mL, diameter-to-height ratio of 1 ∶ 11, sample liquid pH 7, sample flow rate of 1 BV/h, impurity removal with 6 BV of water, and elution with 10 BV of 95％ ethanol at 2 BV/h. The final purity and yield of total alkaloids were 95.10％ , and 2.75％ , respectively. Pearson correlation analysis revealed a significant positive correlation between alkaloid content and colon cancer cell inhibition rate. These results demonstrate a clear dose-effect relationship between alkaloid content and anti-tumor activity, indicating the feasibility of the extraction and purification process for developing anti-colon cancer drugs.

An efficient method was established for detecting the potential aneugenic activity of chemical substances by combining the micronucleus(MN) test with fluorescence in situ hybridization(FISH) technology. Using mouse lymphoma cells(L5178Y tk+/–) and human lymphoblastoid cells(TK6) as models, the genotoxic effects of colchicine, vincristine, and mitomycin C were analyzed. The results showed that more than 70.2％ and 50.5％ of the micronuclei induced by colchicine and vincristine contained centromeric signals, respectively, indicating that these drugs mainly induced aneuploidy through the mechanism of chromosome loss. In contrast, 85.9％ of the micronuclei induced by mitomycin C lacked centromeric signals, confirming that it acted through chromosome breakage. By integrating cellular-level(MN test, formation rate) and molecular-level(FISH, centromere detection) analyses, this method enabled precise discrimination between aneugens and DNA clastogens. This multi-dimensional detection system could significantly improve the accuracy of genotoxicity mechanism determination and hold important application values in fields such as drug safety evaluation, environmental toxicological assessment, and clinical diagnosis.

The solubility values of cannabidiol(1) in n-hexane, n-heptane, 80% ethanol, and 90% ethanol were determined, then these solubility data were fitted using the Apelblat equation. After that, the Gibbs free energy change of dissolution(ΔG), the enthalpy change of dissolution(ΔH), and the change of dissolution(ΔS) of 1 were calculated in different solvents using the van’t Hoff equation. On this basis, the crystallization thermodynamicsof 1 was studied. The results showed that the solubility of 1 exhibited a positive correlation with temperature, and its solubility in the aforementioned solvents follows the descending order: 90％ ethanol>80％ ethanol>n-hexane>n-heptane. The correlation coefficients R2 of the Apelblat’s equations were all greater than 0.99, indicating a good correlation. Both ΔH and ΔS were greater than 0 during the dissolution process of 1, showing this process was an endothermic and entropy-increasing process. These results could provide certain guidance for the extraction and crystallization of 1 during the processing.

A method for preparing test samples for visual inspection process of vaccine injection that meets pharmacopoeia requirements was established. First of all, based on the regulatory requirements, product and process evaluation, and the principle of visual inspection equipment, the types and materials of test samples were confirmed. Next, particles corresponding to the types and materials were prepared, and the target particles were screened out by the sieving method, and then added into the product containers. After that, the detection rate was calculated from multiple inspections to evaluate the detectability of particles, thereby selecting suitable defective products. Finally, considering the final use of the test samples, defective products with appropriate detection rates were selected to comprise a test sample set. This method can successfully prepare test samples for the visual inspection process of vaccine injections that meet pharmacopoeia requirements, providing practical and feasible solutions for manufacturers in terms of the type selection, particle size screening and quality evaluation of test samples.