CN110054565A - A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate - Google Patents

A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate Download PDF

Info

Publication number
CN110054565A
CN110054565A CN201910193003.4A CN201910193003A CN110054565A CN 110054565 A CN110054565 A CN 110054565A CN 201910193003 A CN201910193003 A CN 201910193003A CN 110054565 A CN110054565 A CN 110054565A
Authority
CN
China
Prior art keywords
column
eicosapentaenoic acid
ethyl ester
acid ethyl
purity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201910193003.4A
Other languages
Chinese (zh)
Inventor
孙国威
阮必武
穆宁
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
WUXI GALAK-TECH Co Ltd
Original Assignee
WUXI GALAK-TECH Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by WUXI GALAK-TECH Co Ltd filed Critical WUXI GALAK-TECH Co Ltd
Priority to CN201910193003.4A priority Critical patent/CN110054565A/en
Publication of CN110054565A publication Critical patent/CN110054565A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00Preparation of carboxylic acid esters
    • C07C67/48Separation; Purification; Stabilisation; Use of additives
    • C07C67/56Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C69/00Esters of carboxylic acids; Esters of carbonic or haloformic acids
    • C07C69/52Esters of acyclic unsaturated carboxylic acids having the esterified carboxyl group bound to an acyclic carbon atom
    • C07C69/587Monocarboxylic acid esters having at least two carbon-to-carbon double bonds

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Fats And Perfumes (AREA)

Abstract

The present invention relates to medical pharmaceutical field, specifically a kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate.This method uses C18 reverse-phase chromatography filler, the eicosapentaenoic acid ethyl ester raw material of purity 70-80% is once purified and obtains the eicosapentaenoic acid ethyl ester of high-purity, cost is relatively low for it, yield is higher, EPA-EE purity produced can reach 99.5% or more, urgent need of the medical market to high-purity EPA E can be met, be conducive to industrial applications.

Description

A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate
Technical field
The present invention relates to medical pharmaceutical field, specifically a kind of chromatogram purification side of High Purity Ethyl Eicosapentaenoate Method.
Background technique
Eicosapentaenoic acid (EPA) is one of several omega-3 type polyunsaturated fatty acids needed by human, treatment and Prevention and treatment cardiovascular and cerebrovascular disease, inhibits tumour and prevention senile dementia etc. to all have preferable curative effect at inflammation.High-purity Eicosapentaenoic acid ethyl ester (EPA-EE) can be used as a kind of bulk pharmaceutical chemicals, be applied to medical pharmaceutical field.Such as Irish biology system The drug Vascepa that medicine company Amarin is developed is exactly the eicosapentaenoic acid ethyl ester (EPA-EE) for being greater than 96% using purity, is used In treatment hypertriglyceridemia and dyslipidemia.Therefore, high-purity EPA E future will be widely used in bulk pharmaceutical chemicals And medicine intermediate.
The current published main method for preparing EPA-EE have urea adduct crystallisation (United States Patent (USP) 6664405), Metal salts as precipitator (United States Patent (USP) 6846942) and molecularly distilled (United States Patent (USP) 8889895), but above-mentioned most of method is also It is the level for resting on pigment, cholesterol and a certain amount of saturated fatty acid in simple removal raw material fish oil, EPA-EE obtained Purity is extremely difficult to 80% or more, is unable to satisfy high-purity requirement.For high-purity EPA E(97% or more) purifying preparation Technology is few, and has respective defect.If Qing company utilizes the technology of silver nitrate diatomite chromatography EPA-EE, produce Rate is less than 30%, and raw material needs to reach 90% or more purity, and furthermore there are heavy metal pollution risks for product;Domestic production method is more Chromatogram purification EPA-EE is carried out using the preparative C18 reverse phase filler of Japanese great Cao or YMC company, but that there are material costs is high, Chromatographic step is more, yield is not high, purity is difficult to the problems such as further increasing.As 102391112 A of CN uses YMC-Pack ODS-AQ reverse phase filler carries out EPA-EE purification, but its raw material needs to reach 90% or more purity, and applied sample amount is also relatively low.CN 103833552 A refer to a kind of polymer reversed-phase resin for chromatographic step, but the resin is a large amount of organic molten using preceding needing Agent and time are swollen, and there are monomer, crosslinking agent and pore-foaming agents etc. to remain risk, and in addition the process employs gradients to wash De-, this is also unfavorable for industrial amplification.108640840 A of CN has invented a kind of multicolumn continuous chromatography method and has purified for EPA, but This method needs complicated equipment and accurate instrument controlling, and equipment investment is larger.
Summary of the invention
The problem to be solved in the present invention is to provide a kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate, the colors Spectrum purification process can once purify to obtain the eicosapentaenoic acid ethyl ester of high-purity, and cost is relatively low, and yield is higher, is conducive to Industrial applications.
To solve the above problems, taking following technical scheme:
The characteristics of chromatographic purification method of High Purity Ethyl Eicosapentaenoate of the invention be the following steps are included:
A. the use of C18 reverse-phase chromatography filler is chromatogram purification filler, is dissolved with isopropanol, dress column homogenate is made;
B. dynamic axial compression column is loaded, 1800-2200psi is arranged in filling pressure, flows opposite chromatographic column with balance after installing It is balanced;
C. the eicosapentaenoic acid ethyl ester solution of 70-80% is chosen as sample, 5 times is diluted with methanol solution, to UV detector After baseline is steady, sample solution sample introduction;
D. continue to rinse chromatographic column with balance mobile phase after sample introduction, flush volume is no less than 10 column volumes;
E. the efflux for collecting the 9th column volume is eicosapentaenoic acid ethyl ester component, and collected volume is 0.8-1 times of cylinder Product;
F. after the completion of eicosapentaenoic acid ethyl ester Fraction collection, chromatographic column is rinsed with pure methanol and is no less than 2 column volumes;
G. the chromatogram purification that c ~ f step can be carried out continuously eicosapentaenoic acid ethyl ester is repeated;
H. the eicosapentaenoic acid ethyl ester component collected to back is evaporated under reduced pressure, and temperature is 50 ~ 60 degree, in solution After methanol content evaporating completely, High Purity Ethyl Eicosapentaenoate product is both obtained.
Wherein, the C18 reverse-phase chromatography filler selects Galaksil UP-C18H filler.
The methanol aqueous solution that the balance mobile phase is 85-88%, dosage are at least 2-3 times of column volume.
Above scheme is taken, is had the advantage that
The chromatographic purification method of High Purity Ethyl Eicosapentaenoate of the invention uses C18 reverse-phase chromatography filler, by purity 70- 80% eicosapentaenoic acid ethyl ester raw material, which once purifies, obtains the eicosapentaenoic acid ethyl ester of high-purity, and cost is relatively low, yield Higher, EPA-EE purity produced can reach 99.5% or more, can meet medical market and be essential to the urgent of high-purity EPA E It asks, is conducive to industrial applications.
Detailed description of the invention
Fig. 1: the chromatogram purification map of eicosapentaenoic acid ethyl ester, arrow show collection object;
Fig. 2: the gas chromatographic analysis figure of object, purity 99.94% are collected in embodiment 1;
Fig. 3: the gas chromatographic analysis figure of object, purity 99.92% are collected in embodiment 2;
Fig. 4: the gas chromatographic analysis figure of object, purity 99.82% are collected in embodiment 3.
Specific embodiment
The present invention is described in further details with reference to embodiments.
Embodiment one
The chromatographic purification method of the High Purity Ethyl Eicosapentaenoate of the present embodiment the following steps are included:
A. the use of C18 reverse-phase chromatography filler is chromatogram purification filler, is dissolved with isopropanol, dress column homogenate is made;
B. dynamic axial compression column is loaded, 1800psi is arranged in filling pressure, is carried out after installing with balance flowing chromatographic column relatively flat Weighing apparatus;
C. the eicosapentaenoic acid ethyl ester solution of selection 70% dilutes 5 times with methanol solution, to UV detector base as sample After line is steady, sample solution sample introduction;
D. continue to rinse chromatographic column with balance mobile phase after sample introduction, flush volume is no less than 10 column volumes;
E. separating spectrum such as Fig. 1, collecting efflux shown in arrow in the 9th column volume, that is, figure is eicosapentaenoic acid ethyl ester Component, collected volume are 0.8 times of column volume;
F. after the completion of eicosapentaenoic acid ethyl ester Fraction collection, chromatographic column is rinsed with pure methanol and is no less than 2 column volumes;
G. the chromatogram purification that c ~ f step can be carried out continuously eicosapentaenoic acid ethyl ester is repeated;
H. the eicosapentaenoic acid ethyl ester component collected to back is evaporated under reduced pressure, and temperature is 50 degree, to the first in solution After alcohol component evaporating completely, High Purity Ethyl Eicosapentaenoate product is both obtained, is tested by GC, purity 99.94%, such as schemed Shown in 2.
Embodiment two
The chromatographic purification method of the High Purity Ethyl Eicosapentaenoate of the present embodiment the following steps are included:
A. the use of C18 reverse-phase chromatography filler is chromatogram purification filler, is dissolved with isopropanol, dress column homogenate is made;
B. dynamic axial compression column is loaded, 2000psi is arranged in filling pressure, is carried out after installing with balance flowing chromatographic column relatively flat Weighing apparatus;
C. the eicosapentaenoic acid ethyl ester solution of selection 75% dilutes 5 times with methanol solution, to UV detector base as sample After line is steady, sample solution sample introduction;
D. continue to rinse chromatographic column with balance mobile phase after sample introduction, flush volume is no less than 10 column volumes;
E. the efflux for collecting the 9th column volume is eicosapentaenoic acid ethyl ester component, and collected volume is 0.9 times of column volume;
F. after the completion of eicosapentaenoic acid ethyl ester Fraction collection, chromatographic column is rinsed with pure methanol and is no less than 2 column volumes;
G. the chromatogram purification that c ~ f step can be carried out continuously eicosapentaenoic acid ethyl ester is repeated;
H. the eicosapentaenoic acid ethyl ester component collected to back is evaporated under reduced pressure, and temperature is 55 degree, to the first in solution After alcohol component evaporating completely, High Purity Ethyl Eicosapentaenoate product is both obtained, is tested by GC, purity 99.92%, such as schemed Shown in 3.
Embodiment three
The chromatographic purification method of the High Purity Ethyl Eicosapentaenoate of the present embodiment the following steps are included:
A. the use of C18 reverse-phase chromatography filler is chromatogram purification filler, is dissolved with isopropanol, dress column homogenate is made;
B. dynamic axial compression column is loaded, 2200psi is arranged in filling pressure, is carried out after installing with balance flowing chromatographic column relatively flat Weighing apparatus;
C. the eicosapentaenoic acid ethyl ester solution of selection 80% dilutes 5 times with methanol solution, to UV detector base as sample After line is steady, sample solution sample introduction;
D. continue to rinse chromatographic column with balance mobile phase after sample introduction, flush volume is no less than 10 column volumes;
E. the efflux for collecting the 9th column volume is eicosapentaenoic acid ethyl ester component, and collected volume is 1 times of column volume;
F. after the completion of eicosapentaenoic acid ethyl ester Fraction collection, chromatographic column is rinsed with pure methanol and is no less than 2 column volumes;
G. the chromatogram purification that c ~ f step can be carried out continuously eicosapentaenoic acid ethyl ester is repeated;
H. the eicosapentaenoic acid ethyl ester component collected to back is evaporated under reduced pressure, and temperature is 60 degree, to the first in solution After alcohol component evaporating completely, High Purity Ethyl Eicosapentaenoate product is both obtained, is tested by GC, purity 99.82%, such as schemed Shown in 4.
In above-described embodiment, the C18 reverse-phase chromatography filler selects Galaksil UP-C18H filler;The balance flowing It is mutually the methanol aqueous solution of 85-88%, dosage is at least 2-3 times of column volume.
The chromatographic purification method of High Purity Ethyl Eicosapentaenoate of the invention uses C18 reverse-phase chromatography filler, will be pure The eicosapentaenoic acid ethyl ester raw material of degree 70-80% once purifies and obtains the eicosapentaenoic acid ethyl ester of high-purity, cost compared with Low, yield is higher, and EPA-EE purity produced can reach 99.5% or more, can meet medical market to high-purity EPA E's Urgent need is conducive to industrial applications.

Claims (3)

1. a kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate, it is characterised in that the following steps are included:
A. the use of C18 reverse-phase chromatography filler is chromatogram purification filler, is dissolved with isopropanol, dress column homogenate is made;
B. dynamic axial compression column is loaded, 1800-2200psi is arranged in filling pressure, flows opposite chromatographic column with balance after installing It is balanced;
C. the eicosapentaenoic acid ethyl ester solution of 70-80% is chosen as sample, 5 times is diluted with methanol solution, to UV detector After baseline is steady, sample solution sample introduction;
D. continue to rinse chromatographic column with balance mobile phase after sample introduction, flush volume is no less than 10 column volumes;
E. the efflux for collecting the 9th column volume is eicosapentaenoic acid ethyl ester component, and collected volume is 0.8-1 times of cylinder Product;
F. after the completion of eicosapentaenoic acid ethyl ester Fraction collection, chromatographic column is rinsed with pure methanol and is no less than 2 column volumes;
G. the chromatogram purification that c ~ f step can be carried out continuously eicosapentaenoic acid ethyl ester is repeated;
H. the eicosapentaenoic acid ethyl ester component collected to back is evaporated under reduced pressure, and temperature is 50 ~ 60 degree, in solution After methanol content evaporating completely, High Purity Ethyl Eicosapentaenoate product is both obtained.
2. the chromatographic purification method of High Purity Ethyl Eicosapentaenoate as described in claim 1, it is characterised in that the C18 Reverse-phase chromatography filler selects Galaksil UP-C18H filler.
3. the chromatographic purification method of High Purity Ethyl Eicosapentaenoate as described in claim 1, it is characterised in that described flat The mobile phase that weighs is the methanol aqueous solution of 85-88%, and dosage is at least 2-3 times of column volume.
CN201910193003.4A 2019-03-15 2019-03-15 A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate Pending CN110054565A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910193003.4A CN110054565A (en) 2019-03-15 2019-03-15 A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910193003.4A CN110054565A (en) 2019-03-15 2019-03-15 A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate

Publications (1)

Publication Number Publication Date
CN110054565A true CN110054565A (en) 2019-07-26

Family

ID=67316893

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910193003.4A Pending CN110054565A (en) 2019-03-15 2019-03-15 A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate

Country Status (1)

Country Link
CN (1) CN110054565A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020177728A1 (en) 2019-03-05 2020-09-10 四川国为制药有限公司 Fatty acid composition and application thereof
CN113698296A (en) * 2020-05-22 2021-11-26 中国科学院大连化学物理研究所 Method for purifying EPA (eicosapentaenoic acid) by using C18 reverse phase silica gel
CN113698984A (en) * 2021-08-27 2021-11-26 常熟纳微生物科技有限公司 Separation and purification method of eicosapentaenoic acid in fish oil
CN113831244A (en) * 2020-06-24 2021-12-24 北京创新通恒科技有限公司 Separation equipment and process method for purifying high-purity EPA-ee
CN115015458A (en) * 2022-07-01 2022-09-06 江苏汉邦科技股份有限公司 Split-flow chromatography system and method for preparing ethyl eicosapentaenoate by using split-flow chromatography system

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1634852A (en) * 2004-10-25 2005-07-06 浙江大学 Process for preparing and separating eicosapentaenoic acid ethyl ester and docosahexenoic acid ethyl ester
CN102285880A (en) * 2011-06-14 2011-12-21 国家海洋局第三海洋研究所 Method for preparing ethyl eicosapentaenate (EPA) and ethyl docosahexaenoate (DHA)
CN102391112A (en) * 2011-10-31 2012-03-28 赵永俊 Method for industrialized production of eicosapentaenoic acid ethyl ester
CN103833552A (en) * 2014-03-21 2014-06-04 上海朴颐化学科技有限公司 Method for industrially purifying ethyl eicosapentaenoate
CN104529772A (en) * 2014-12-17 2015-04-22 浙江大学 Method for preparing high-purity EPA ester and DHA ester monomers by virtue of simulated moving bed chromatography
CN105272844A (en) * 2014-06-09 2016-01-27 北京创新通恒科技有限公司 Method for purifying high-purity fish oil EPA(eicosapentaenoic acid) ethyl ester and DHA(docosahexaenoic acid) ethyl ester
US20160208296A1 (en) * 2013-08-30 2016-07-21 Bizen Chemical Co., Ltd. Method for producing high purity omega-3 fatty acid ethyl ester
CN107311866A (en) * 2017-06-15 2017-11-03 浙江大学宁波理工学院 The method that eicosapentaenoic acid esters and docosahexaenoic acid ester are isolated and purified with SMBC

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1634852A (en) * 2004-10-25 2005-07-06 浙江大学 Process for preparing and separating eicosapentaenoic acid ethyl ester and docosahexenoic acid ethyl ester
CN102285880A (en) * 2011-06-14 2011-12-21 国家海洋局第三海洋研究所 Method for preparing ethyl eicosapentaenate (EPA) and ethyl docosahexaenoate (DHA)
CN102391112A (en) * 2011-10-31 2012-03-28 赵永俊 Method for industrialized production of eicosapentaenoic acid ethyl ester
US20160208296A1 (en) * 2013-08-30 2016-07-21 Bizen Chemical Co., Ltd. Method for producing high purity omega-3 fatty acid ethyl ester
CN103833552A (en) * 2014-03-21 2014-06-04 上海朴颐化学科技有限公司 Method for industrially purifying ethyl eicosapentaenoate
CN105272844A (en) * 2014-06-09 2016-01-27 北京创新通恒科技有限公司 Method for purifying high-purity fish oil EPA(eicosapentaenoic acid) ethyl ester and DHA(docosahexaenoic acid) ethyl ester
CN104529772A (en) * 2014-12-17 2015-04-22 浙江大学 Method for preparing high-purity EPA ester and DHA ester monomers by virtue of simulated moving bed chromatography
CN107311866A (en) * 2017-06-15 2017-11-03 浙江大学宁波理工学院 The method that eicosapentaenoic acid esters and docosahexaenoic acid ester are isolated and purified with SMBC

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
朱靖博等: ""超临界流体萃取-色谱法提纯鱼油乙酯中EPA-EE和DHA-EE"", 《大连工业大学学报》 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020177728A1 (en) 2019-03-05 2020-09-10 四川国为制药有限公司 Fatty acid composition and application thereof
CN113698296A (en) * 2020-05-22 2021-11-26 中国科学院大连化学物理研究所 Method for purifying EPA (eicosapentaenoic acid) by using C18 reverse phase silica gel
CN113831244A (en) * 2020-06-24 2021-12-24 北京创新通恒科技有限公司 Separation equipment and process method for purifying high-purity EPA-ee
CN113698984A (en) * 2021-08-27 2021-11-26 常熟纳微生物科技有限公司 Separation and purification method of eicosapentaenoic acid in fish oil
CN115015458A (en) * 2022-07-01 2022-09-06 江苏汉邦科技股份有限公司 Split-flow chromatography system and method for preparing ethyl eicosapentaenoate by using split-flow chromatography system

Similar Documents

Publication Publication Date Title
CN110054565A (en) A kind of chromatographic purification method of High Purity Ethyl Eicosapentaenoate
Gao et al. Simultaneous purification of dihydrotanshinone, tanshinone I, cryptotanshinone, and tanshinone IIA from Salvia miltiorrhiza and their anti-inflammatory activities investigation
CN104529772B (en) A kind of simulated moving bed chromatography prepares high-purity EPA ester and the method for DHA ester monomer
CN105272844B (en) Method for purifying high-purity fish oil EPA(eicosapentaenoic acid) ethyl ester and DHA(docosahexaenoic acid) ethyl ester
Wang et al. Direct enantiomeric resolutions of chiral triazole pesticides by high-performance liquid chromatography
CN103826715B (en) The chromatography separating method of heating
Xiang et al. Unusual chromatographic enantioseparation behavior of naproxen on an immobilized polysaccharide-based chiral stationary phase
EP3029021A1 (en) Method for separating fat-soluble material by simulated moving bed chromatography, and device for same
CN111039761B (en) Method for purifying cannabidiol
CN105859803B (en) A kind of preparation method of galloyl glucose
Yang et al. Enrichment and purification of syringin, eleutheroside E and isofraxidin from Acanthopanax senticosus by macroporous resin
Liu et al. Offline preparative 2-D polar-copolymerized reversed-phase chromatography× zwitterionic hydrophilic interaction chromatography for effective purification of polar compounds from Caulis Polygoni Multiflori
Li et al. Development of a method to extract and purify target compounds from medicinal plants in a single step: online hyphenation of expanded bed adsorption chromatography and countercurrent chromatography
Sun et al. “Two-dimensional” molecularly imprinted solid-phase extraction coupled with crystallization and high performance liquid chromatography for fast semi-preparative purification of tannins from pomegranate husk extract
Fagan et al. Rapid isolation of omega‐3 long‐chain polyunsaturated fatty acids using monolithic high performance liquid chromatography columns
CN108191639A (en) It is a kind of that the method that shikimic acid extract is prepared in waste liquid is chromatographed from ginkgo biloba p.e
Kumari et al. Chromatographic techniques: types, principles, and applications
CN103787863A (en) Method for preparing EPA through preparative high performance liquid chromatography
CN110256250B (en) Method for preparing high-purity conjugated linoleate by using simulated moving bed
Arab et al. A benign process for the recovery of solanesol from tomato leaf waste
CN108218757A (en) To the method for splitting of 2- (4- propyl pyrrole alkane -2- ketone)-butyramide diastereoisomer
CN109251156A (en) The preparation method of astaxanthin diester reference material in a kind of krill
Wang et al. Urea complexation combined with rapid preparative reversed-phase liquid chromatography to separate α-linolenic acid from perilla seed oil: Purity, yield, and oxidation stability
Adili et al. Simultaneous determination of loading capacity and selectivity in preparative off-line two-dimensional separation: An application for purification of corilagin from Pomegranate flower extracts
CN104557542B (en) A kind of Supercritical fluid chromatography prepares the method for high purity EPA ester and DHA ester monomer

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20190726

WD01 Invention patent application deemed withdrawn after publication