医用胶原修复膜病毒灭活/去除工艺的验证和评价

目的验证和评价医用胶原修复膜制备工艺中过氧化氢溶液、低p H孵放和γ射线辐照灭活/去除病毒的可行性。方法以水疱性口炎病毒(vesicular stomatitis virus,VSV)、伪狂犬病病毒(pseudorabies virus,PRV)、呼肠弧病毒Ⅲ(respiratory enteric orphan virusⅢ,Reo 3)、猪细小病毒(porcine parvovirus,PPV)作为指示病毒,采用非洲绿猴肾细胞(Vero)和猪肾细胞(PK-15)进行病毒增殖和感染性评价,Karber法测定病毒滴度;分别对牛腱片样品进行3%过氧化氢、低p H孵放处理(pH 3.4±0.3),检测病毒灭活/去除效果;将医用胶原修复膜中间品进行~(60)Coγ射线辐照(剂量为25 k Gy),检测病毒灭活/去除效果。结果经3%过氧化氢溶液处理1 h后,样品VSV和PRV的病毒灭活值均大于4 Logs;经低p H孵放处理14 d后,样品中已检测不到VSV和PRV,病毒灭活值分别为6.55和5.59 Logs;经25 k Gy剂量~(60)Coγ射线辐照处理后,样品中VSV、PRV、Reo3和PPV均被有效灭活,病毒灭活值分别为5.64、4.35、4.87和5.36 Logs。结论医用胶原修复膜制备工艺中的3种灭活/去除病毒步骤均有效,经灭活/去除病毒后的产品质量安全可靠。     

S/D法及干热法对人凝血因子Ⅷ制品中猪伪狂犬病病毒和猪细小病毒灭活效果的验证

目的验证S/D法及干热法对人凝血因子Ⅷ(FⅧ)制品中猪伪狂犬病病毒(pesdorabies virus,PRV)和猪细小病毒(porcine parvovirus,PPV)的灭活效果。方法以PRV和PPV为指示病毒,模拟FⅧ生产工艺中的S/D及干热病毒灭活工艺,采用96孔板微量细胞病变法检测3批FⅧ半成品的残留病毒滴度。结果批号为201203002、2012-04003、201204004 3批FⅧ半成品经(25±1)℃S/D灭活处理15 min后,PRV滴度分别下降≥6.5、≥6.8、≥6.8 lg TCID50/0.1 ml;经(100±2)℃干热灭活30 min后,PPV滴度分别下降4.00、3.92、3.94 lg TCID50/0.1 ml。结论 S/D法及干热法分别对FⅧ制品中PRV和PPV具有良好的灭活效果,本实验为凝血因子类制品的病毒灭活验证工艺的研究奠定了基础。     

静注人免疫球蛋白新生产工艺病毒灭活/去除效果的验证及评估

目的对静注人免疫球蛋白(intravenous human immunoglobulin,IVIG)新生产工艺的病毒灭活/去除效果进行验证及评估。方法选择4种脂包膜病毒[人免疫缺陷综合征病毒(human immunodeficiency virus,HIV)、伪狂犬病病毒(pseudorabies virus,PRV)、辛德毕斯病毒(Sindbis virus,SV)和水疱性口炎病毒(vesicular stomatitis virus,VSV)]及非脂包膜病毒[猪细小病毒(porcine parvovirus,PPV)]作为验证病毒,在缩小的生产规模条件下考察辛酸钠沉淀/深层过滤、低pH孵放和纳米膜过滤步骤对一种或几种指示病毒的灭活/去除能力。结果辛酸钠沉淀/深层过滤步骤可灭活/去除PPV 1.88 Log;低pH孵放对HIV、PRV、SV和VSV的灭活效果最低分别为≥5.22、≥4.26、≥6.56和≥5.69 Log;Bio EX纳米膜可去除PPV达4 Log以上。结论 IVIG新生产工艺的病毒灭活/去除效果合格,可有效灭活/去除未知的、新出现的病原体。     

不同配方的冻干保护剂对人凝血因子Ⅷ制品干热法灭活猪细小病毒效果的影响

目的研究不同配方的冻干保护剂对人凝血因子Ⅷ制品干热法灭活非脂包膜指示病毒猪细小病毒(porcine parvovirus,PPV)效果的影响。方法取人凝血因子Ⅷ原液,分别加入A、B、C 3种配方(氯化钠浓度为C6 LgTCID50/ml的指示病毒PPV,进行冻干、干热法灭活(100℃30 min),检测残余PPV滴度;用筛选出的最佳配方制备3批人凝血因子Ⅷ半成品,进行冻干和干热法灭活,检测残余PPV滴度,验证PPV灭活效果;按照《中国药典》三部(2010版)人凝血因子Ⅷ的成品检测要求对人凝血因子Ⅷ效价、外观、水分、复溶时间和复溶后外观进行检测。结果在100℃30 min条件下,可有效灭活配方A制备的人凝血因子Ⅷ半成品中的指示病毒PPV,确定配方A为最佳冻干保护剂配方;3批凝血因子Ⅷ经干热灭活后,可使残余PPV滴度下降(4.08±0.02)LgTCID50/0.1 ml,且灭活过程对人凝血因子Ⅷ的生物学活性无明显影响,步骤活性回收率为(91.1±2)%。结论已成功研制出1种冻干保护剂配方,应用干热灭活法对人凝血因子Ⅷ制品中非脂包膜病毒PPV具有较好的灭活效果,该方法与有机溶剂/表面活性剂(solvent/detergent,S/D)法联合去除/灭活病毒,可有效提高人凝血因子Ⅷ产品的安全性。     

重组人IL-12病毒去除/灭活工艺的建立及验证

目的建立重组人白细胞介素-12(recombinant human IL-12,rhIL-12)的病毒去除/灭活工艺,并进行验证。方法采用预过滤器(Viresolve Shield,纳米滤膜3.1 cm2)和除细小病毒过滤器(Viresolve Pro,纳米滤膜3.1 cm2)串联过滤,样品体积为90 ml,过滤时间为2 h,安全系数为1.88,压力为30 psi,建立rhIL-12病毒去除工艺,分析该工艺对产品的比活性及回收率的影响,并以猪细小病毒(porcine parvovirus,PPV)作为指示病毒,对该工艺进行病毒去除效果验证;采用低pH孵放法(用1 mol/L HCl调pH值至3.8±0.1,室温放置180 min后,用1 mol/L NaOH调pH值至7.4)建立rhIL-12病毒灭活工艺,分析该工艺对产品的蛋白含量及比活性的影响,并分别以水疱性口炎病毒(vesicular stomatitis virus,VSV)和伪狂犬病病毒(pseudorabies virus,PRV)作为指示病毒,对该工艺进行病毒灭活效果验证。结果纳米膜串联过滤病毒去除工艺中,蛋白回收率为95.14%,比活性为过滤前的95.12%,对rhIL-12活性基本无影响;当滤出液达90 ml时,PPV下降滴度均大于4 log10,符合《生物组织提取制品和真核细胞表达制品的病毒安全性评价技术审评一般原则》的要求。低pH孵放法病毒灭活工艺中,rhIL-12的蛋白含量在病毒灭活前后分别为359和338μg/ml,生物学活性分别为3.392×106和3.356×106 IU,均无明显变化;室温处理180 min后,指示病毒PRV、VSV的下降滴度均4 log10,符合《生物组织提取制品和真核细胞表达制品的病毒安全性评价技术审评一般原则》的要求。结论建立的rhIL-12膜过滤病毒去除工艺和低pH孵放法病毒灭活工艺均可有效地去除/灭活病毒,保证了产品的质量及安全性。     

羧甲基壳聚糖病毒灭活/去除工艺验证

目的对羧甲基壳聚糖病毒灭活/去除工艺进行验证。方法模拟生产条件,选择猪细小病毒(porcine parvovirus,PPV)、伪狂犬病病毒(pseudo rabies virus,PRV)、鸭肝炎病毒Ⅰ型(duck hepatitis virus-Ⅰ,DHV-Ⅰ)、牛滤过性腹泻病毒(bovine viral diarrhea virus,BVDV)作为指示病毒,采用高温碱化和醇洗灭活/去除病毒,Karber法计算病毒滴度,荧光PCR检测病毒灭活/去除效果。结果 3批甲壳素经碱化反应处理,PRV、PPV、BVDV、DHV-Ⅰ的平均灭活对数值分别为≥6.736、≥6.597、≥6.138和≥5.806 log TCID50/0.1 ml;3批羧甲基壳聚糖经醇洗处理,PRV、PPV、BVDV、DHV-Ⅰ的平均灭活对数值分别为≥6.763、≥6.569、≥6.167和≥5.587 log TCID50/0.1 ml。碱化反应与醇洗处理前感染PRV、PPV、BVDV、DHV-Ⅰ样品荧光PCR检测平均Ct值分别为23.465、23.387,24.873、24.706,26.887、25.376,27.386、24.629,处理后样品的荧光PCR检测平均Ct值均40。结论羧甲基壳聚糖经高温碱化和醇洗反应处理均能有效灭活病毒,保证了产品的安全性。     

重组人凝血因子Ⅷ病毒灭活/去除工艺验证

目的验证重组人凝血因子Ⅷ(recombinant human coagulationⅧ,rhFⅧ)病毒灭活/去除工艺。方法采用S/D法作为rhFⅧ病毒灭活工艺,纳米过滤(20 nm孔径)作为rhFⅧ病毒去除工艺,分析病毒灭活/去除两步工艺对rhFⅧ活性的影响;分别以伪狂犬病毒(pseudorabies virus,PRV)、水疱性口炎病毒(vesicular stomatitis virus,VSV)、小鼠白血病病毒(xenotropic murine leukemia virus,X-MuLV)及小鼠细小病毒(murine minute virus,MMV)作为指示病毒,对上述工艺进行病毒灭活/去除效果验证。结果 S/D灭活工艺中,3批制品的活性收率分别为96. 2%、100. 4%和103. 2%;(24±2)℃处理180 min后,指示病毒PRV、VSV和X-MuLV滴度降低量(Log10)虽然均4,但盲传3代,仍未检出病毒。纳米过滤工艺中,3批制品蛋白回收率均大于98%,活性回收率均大于90%,纳米过滤120 min,MMV滴度降低量(Log10) 4。结论建立的rhFⅧ病毒灭活/去除工艺,可有效灭活/去除病毒,保证制品的质量和安全。     

钴~(60)-γ射线辐照法对骨蜡中指示病毒灭活效果的验证

目的验证钴60-γ射线辐照对骨蜡中模拟污染指示病毒的灭活效果。方法将固体骨蜡制成腔壁0.7 cm厚的空心圆柱体的辐照用样品,空腔中分别加入6.61 Lg PFU/ml辛德毕(Sindbis)病毒、7.07 LgTCID50/0.1 ml脑心肌炎病毒(encephalomyocarditis virus,EMCV)和6.01 LgTCID50/0.1 ml猪细小病毒(porcine parvovirus,PPV),分别经5、10、15、20及25 kGy的钴60-γ射线进行辐照后,收集样品腔中的病毒液,采用噬斑形成法检测Sindbis病毒滴度,采用微量半数细胞病变法检测PPV和EMCV滴度。结果经不同剂量kGy钴60-γ射线辐照,Sindbis病毒、EMCV及PPV的病毒滴度随辐照剂量的增加而下降,辐照剂量增加至25 kGy时,可灭活3种病毒的量分别达6.03⁶.60 LgPFU/ml、6.256.60 LgPFU/ml、6.25⁶.32 Lg TCID50/0.1 ml和4.756.32 Lg TCID50/0.1 ml和4.75⁴.88 LgTCID50/0.1 ml以上。结论 25 kGy的钴60-γ射线对骨蜡中的包膜和无包膜病毒均有较好的灭活效果。     

低pH胃蛋白酶-甲苯消化法灭活破伤风免疫血浆中脂包膜病毒效果验证

目的验证低pH条件下胃蛋白酶-甲苯消化法对不同核酸类型的脂包膜病毒的灭活效果。方法以水疱性口炎病毒(Vesicular stomatitis virus,VSV)作为RNA指示病毒,以伪狂犬病病毒(Pseudorabies virus,PRV)作为DNA指示病毒,将破伤风免疫血浆样品经低pH(3.2±0.2)、0.2%甲苯、6～12活力单位胃蛋白酶处理后各取27 ml,分别加入3 ml指示病毒(9∶1),在(30.0±1)℃水浴中分别振摇10、30、60、90 min灭活病毒。以Vero细胞、PK-15细胞为基质,采用96孔细胞病变法检测残余病毒滴度,验证病毒灭活效果。结果破伤风免疫血浆样品经低pH胃蛋白酶及甲苯消化处理90 min后,VSV和PRV两种指示病毒的灭活效果分别为3.12～3.88和5.25～5.38 logTCID50/0.1 ml。结论采用低pH胃蛋白酶-甲苯消化法对破伤风免疫血浆中PRV灭活效果较好,而对VSV灭活效果有待提高。     

猪细小病毒荧光定量PCR检测方法的建立及初步应用

目的建立猪细小病毒(porcine parvovirus,PPV)荧光定量PCR检测方法,并进行验证及初步应用。方法根据GenBank中登录的PPV NADL-2株序列,针对VP2区设计引物,以提取的PPV核酸为模板,进行荧光定量PCR扩增;优化反应体系及反应条件,并进行专属性、重复性和敏感性验证。用建立的荧光定量PCR法检测辛酸沉淀及L、P、S公司生产的纳米膜过滤器去除制品中PPV的效果。结果优化后的荧光定量PCR反应体系:Eva Green预混液7.5μl,上下游引物各0.5μl,模板DNA 1μl,补加dH2O至15μl;反应条件:95℃3 min,95℃10 s和60℃10 s,共40个循环;模板浓度的对数值与循环数的相关性较好(R2=0.999),扩增效率为102.5%。该方法可特异性扩增PPV,而对伪狂犬病病毒(pseudorabies virus,PRV)、牛细小病毒(bovine parvovirus,BPV)、鼠细小病毒(minute virus of mice,MVM)及猪肾细胞PK-15无扩增反应;试验内CV为0.79%².81%,试验间CV为1.23%2.81%,试验间CV为1.23%².21%,均<5%,最低检测限为102copies/μl。辛酸沉淀可使样品中PPV浓度下降5 Logs;不同公司生产的20 nm膜滤器过滤量及过滤效果均有明显差异,其中S公司生产的滤器效果最好,可使样品中的PPV滴度下降4 Logs。结论已成功建立了PPV荧光定量PCR检测方法,为快速、准确的检测病毒去除工艺对PPV的去除效果奠定了基础。     

Preparation and properties of poly(Nε,Nε-dicarboxymethyl-l-lysine)

A new ampholytic homopolypeptide, $\text{poly}\text{(N}{}^{\mathrm{\epsilon }}\text{,N}{}^{\mathrm{\epsilon }}\text{-}\text{dicarboxy-methyl-}\text{l}\text{-lysine}\text{)}$, which has one tertiary amino and two carboxyl groups in the side chain has been derived from a hydrochloride salt of poly(L-lysine). The polymer in aqueous solution seems to be in the coil form with locally extended structure (LES) at neutral pH. In both the acidic and alkaline regions, the molar ellipticity of the polymer changes as a result of change in net charge on the side chain. The conformational changes may be from the coil with LES to other coiled forms. 5–7 M NaClO₄ and 80% aqueous methanol induce the α-helix in the polymer at neutral pH. Divalent cations, Cu²⁺ and Ca²⁺, do not induce any remarkably ordered structures such as α-helix or β-structure in the polymer in aqueous solution at any pH. Ultraviolet absorption studies show an absorption peak of the polymer-Cu²⁺ complex near 240 nm. Dependence of the peak intensity on pH at various q values ($\text{q =}\text{[}\text{Cu}{}^{\mathrm{2+}}\text{]}\text{[}\text{residue}\text{]}$) indicates the two steps of the complex formation. At q less than 0.64, the formation is described only with the first step. An average coordination number for Cu²⁺ at the first step was calculated to be about 2 by the method of Mandel and Leyte. The association constant of Cu²⁺ with the residue at the step was determined from the absorption data to be far smaller than that for the Cu²⁺-EDTA complex. The second step of the formation occurs in the case of large q but the absorption data for the second step cannot be obtained exactly due to precipitation.     

Wet Milling of Fe/Al/Al2O3 and Fe2O3/Al/Al2O3 Powder Mixtures

Wet milling of Al₂O₃-aluminide alloy (3A) precursor powders in acetone has been investigated by milling Fe/Al/Al₂O₃ and Fe₂O₃/Al/Al₂O₃ powder mixtures. The influence of the milling process on the physical and chemical properties of the milled powders has been studied. Particle refinement and homogenization were found not to play a dominant role, whereas plastic deformation of the metal particles leads to the formation of dislocations and a highly disarranged polycrystalline structure. Although no chemical reactions among the powder components in Fe₂O₃/Al/Al₂O₃ powder mixtures were observed, the formation of a nanocrystalline, ordered intermetallic FeAl phase in Fe/Al/Al₂O₃ powder mixtures caused by mechanical alloying was detected. Chemical reactions of Fe and Al particle surfaces with the atmosphere and the milling media lead to the formation of highly porous hydroxides on the particle surfaces. Hence the specific surface area of the powders increases, while the powder density decreases during milling. The fraction of Fe oxidized during milling was determined to be 0.13. The fraction of Al oxidized during milling strongly depends on the metal content of the powder mixture. It ranges between 0.4 and 0.8.     

Sintering of Si3N4-Y2O3-Al2O3

Sintering kinetics of the system Si₃N4-Y2O₃-Al₂O3 were determined from measurements of the linear shrinkage of pressed disks sintered isothermally at 1500° to 1700°C. Amorphous and crystalline Si₃N₄ were studied with additions of 4 to 17 wt% Y₂O₃ and 4 wt% A1₂O₃. Sintering occurs by a liquid-phase mechanism in which the kinetics exhibit the three stages predicted by Kingery's model. However, the rates during the second stage of the process are higher for all compositions than predicted by the model. X-ray data show the presence of several transient phases which, with sufficient heating, disappear leaving mixtures of β ' -Si₃N₄ and glass or β '-Si₃N₄, α '-Si₃N₄, and glass. The compositions and amounts of the residual glassy phases are estimated.     

Participation of lewis base on vinyl chloride polymerization with Al(C2H5)3CCl4 catalyst system

The polymerization of vinyl chloride has been investigated using an $\text{Al}\text{(}\text{C}{}_2\text{H}{}_5\text{)}{}_3\text{CCl}{}_4$ catalyst system in the presence of various Lewis bases. Effective Lewis bases are γ-butyrolactone, diglyme and diethylenetriamine which are multidentate. The rate of polymerization is dependent not only on the basicity of the Lewis base used but also on a coordination number of one. The latter is the predominant factor. For the effect of polymeric amines, a tentative hypothesis is discussed.     

Synthesis and Characterization of Ti0.33Ta0.33Nb0.33C and Ti0.33Ta0.33Nb0.33CxN1-x Whiskers

Ta_0.33Ti_0.33Nb_0.33C and Ta_0.33Ti_0.33Nb_0.33C _x N_{1− x} whiskers were synthesized via a carbothermal vapor-liquid-solid growth mechanism in the temperature range 900°-1450°C in Ar or N₂. The optimum temperature was 1250°C. Whiskers were obtained in a yield of 70-90 vol%. The whiskers were 0.5–1 µm in diameter and 10–30 µm in length. The starting materials that produced the highest whisker yield were: TiO₂, Ta₂O₅, Nb₂O₅, C, Ni, and NaCl. C was added to reduce the oxides, and Ni to catalyze whisker growth. NaCl was used as a source of Cl for vapor-phase transportation of Ta and Nb oxochlorides and Ti chlorides to the catalyst. The catalyst metal was recycled several times during the synthesis and was transported as NiCl₂( g ) according to thermodynamic calculations. The rate of formation and the chemical composition of the whiskers depended on the synthesis temperature, the choice of catalyst, and the atmosphere. At low temperatures, the whiskers were enriched in Nb and Ta, whereas the Ti content increased with increased synthesis temperature.