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青島雙元泰和藥業有限公司

青島市城陽區雙元路218號

電話: 0532-55676230
傳真: 0532-55676180

3d历史今天试机号查询:常見問題解答


  • 如何進行詢價?
  • 目錄肽或定制肽詢價,請點擊這里提交信息,或者通過郵件([email protected])、電話(0532-55676230)、傳真(0532-55676180)聯系我們。請提供以下信息:
    • 目錄肽: 目錄肽編號和重量
    • 定制多肽: 多肽序列、修飾、質量、純度(Desalted, >75%, >80%, >90%, >95%, >98%)等
  • 如何在雙元泰和下訂單?
  • 訂單下單請通過郵箱([email protected])、電話(0532-55676230),傳真(0532-55676180)將您的訂單信息提供給我們。您也可以通過谁有大量微信群卖 www.pucvo.com在線提交。
  • 雙元泰和的多肽提供哪些檢測報告?
  • 我們提供所有多肽的質譜報告,對于有純度要求的多肽,我們提供RP-HPLC和COA報告。COA報告包含產品的顏色、性狀、質量等信息。
  • 雙元泰和的產品交貨期是多久?
  • 常規多肽交貨期2-3周,根據多肽的長度和難度時間有所不同。我們會根據您的項目要求及時更新周期和進度。
  • 我的項目應該選擇多少純度的多肽?
  • 常用多肽純度如下:
    1. 多肽純度 >85%: 免疫、多克隆抗體、非敏感篩選。
    2. 多肽純度 >90%: 結構-活性關心研究和生物活性測定。
    3. 多肽純度 >95%: ELISA、酶學、生物活性研究
    4. 多肽純度 >98%: 結構研究/晶體學,NMR和敏感生物測定。
  • 多肽純度和多肽含量的區別?
  • 多肽純度是使用面積歸一HPLC法,測定多肽在214nm的UV吸光度來測定多肽純度的方法。因為水分和鹽分在214nm沒有吸收,該方法測定的多肽純度不包含多肽水分和TFA鹽等。

    谁有大量微信群卖 www.pucvo.com 如果多肽沒有鹽分要求,雙元泰和提供的多肽包含水和少量的TFA鹽。醋酸鹽、鹽酸鹽多肽可以根據客戶要求提供。

    多肽含量是指樣品中多肽類物質的含量,通常情況下合成多肽含量從70%到90%,在某些情況下,多肽含量可能低于30%。
  • 雙元泰和是如何生產多肽的?
  • 雙元泰和多肽使用SPPSLPPS方法進行合成。整個流程符合cGMP規范,下圖是我們質量控制流程:

  • 非HPLC純化的多肽中有哪些雜質?
  • 粗品和脫鹽級別的多肽中多肽和非多肽類雜質:如非全長多肽和多肽后處理的一些原料如DTT、TFA等。

    經過HPLC純化的多肽,仍會有一些一些雜質存在,其中的雜質主要是短肽和微量TFA。

  • 凍干多肽如何保存?
    • 儲存多肽的瓶蓋應該蓋緊,根據實驗計劃將多肽分裝成小包裝。
    • 多肽短期儲存 (三個月以內) 應該儲存在-20℃,更長期的儲存,我們推薦-80℃。
    • 對于凍干多肽和多肽溶液應該避免反復凍融,如果樣品要頻繁使用,建議將樣品分裝成小包裝。
    • 多肽序列中含有C、M、W容易空氣氧化,建議抽真空或者使用惰性氣體?;?。
    • 通常多肽溶液在-4℃可以穩定儲存一周,如果多肽序列中含有不穩定氨基酸或者結構,不建議液體保存。不建議多肽在PH>8的溶液中保存。
  • 多肽如何溶解?
  • 溶解多肽是非常復雜的事情,一般很難一下子確定合適的溶劑。通常是先取一點試驗,在沒有確定合適的溶劑前千萬不要全部溶解。下列方法有助于您選擇合適的溶劑:
    • (1)判定多肽的電荷特定,設定酸性氨基酸Asp(D),Glu(E)和C端COOH為-1;堿性氨基酸Lys(K),Arg(R),His(H)及N端NH2為+1,其它氨基酸的電荷為0。計算出將電荷數。
    • (2)如果凈電荷數>0,多肽為堿性,用水溶解:如果不溶解或溶解性較小,加入醋酸(10%以上);如果多肽還不能溶解,加入少量TFA(25ul)溶解,然后加入500ul水稀釋。
    • (3)如果凈電荷數<0,多肽為酸性,用水溶解;如果不溶解或溶解性不大,加入氨水(25ul)溶解,然后加入500ul水稀釋
    • (4)如果凈電荷數=0,多肽呈中性,一般需要用有機溶劑如乙腈,甲醇或異丙醇,DMSO等溶解?;褂腥私ㄒ樾枰蛩乩慈芙饈杷院艽蟮畝嚯?。
  • How do I estimate the net charge of my peptide?
  • The steps outlined below provide you with a method for determining the best solvent for a synthetic peptide based on its amino acid sequence. It is best to first solubilize a small aliquot of the sample, rather than the entire stock.
    • Assign a value of -1 to each acidic residue. The acidic residues are Asp (D), Glu (E), and the C-terminal -COOH. Assign a value of +1 to each basic residue. The basic residues are Arg (R), Lys (K), His (H), and the N-terminal -NH2.
    • Calculate the overall charge of the synthetic peptide.
    • If the overall charge of the synthetic peptide is a positive value, you have a basic custom peptides. Initially try to dissolve the peptide in water. If the peptide does not dissolve, try 10% and higher solutions of acetic acid. If the peptide still does not dissolve, add TFA (<50?L) to solubilize the peptide and dilute to 1mL with deionized water.
    • If the overall charge of the peptide is a negative value, you have an acidic peptide. Initially try to dissolve the peptide in water. If the custom peptides does not dissolve, add NH4OH (<50?L) and dilute to 1ml with deionized water.
    • If the overall charge of the synthetic peptide is zero, your custom peptides is considered neutral. Neutral peptides may require the addition of organic solvents, such as acetonitrile, methanol, or isopropanol. The addition of denaturants, such as urea or guanidinium-HCL may also be necessary.
  • If my peptide has a purity of 90%, what are the other 10%?
  • If a synthetic peptide has a purity of 90%, the other 10% contains synthetic peptides that have shorter sequences, truncated sequences, sequences with incomplete deprotectionly deprotected sequences
    • Peptide sequences modified during cleavage (reattachment of protecting groups at other locations on the synthetic peptide)
    • Synthetic peptides that have undergone side reactions
  • How do I design my peptide?
  • The steps outlined below provide you with a method for a good idea to choose the terminal ends of the custom peptide dependent on the natural occurrence of the peptide sequence:
    • The custom peptide should mimic an internal sequence of a protein. The peptide should not be charged at the ends. The N-terminus of the custom peptide should be acetylated and the C-terminus should be amidated.
    • If the synthetic peptide sequence is the C-terminal end of a protein, the C-terminus should be the free acid and the N-terminus should be acetylated.
    • If the synthetic peptide sequence is the N-terminal end of a protein, the C-terminus should be an amidated and the N-terminus should be in the natural free amine form.
    • If the custom peptide is for cytotoxic T-cell epitope studies, a free amino group at the N-terminus and a free acid at the C-terminus are necessary. These ends are the natural equivalents to the synthetic peptide fragments, processed intracellularly from whole proteins.
    • If the custom peptide is for antibody production, please check the technical resources section of our website.
  • What are the characteristics of carrier protein KLH vs. BSA?
  • Both KLH and BSA are common carrier proteins which are long peptides. The molecular weight of BSA is much smaller than KLH. However, BSA is much more soluble and immunogenic. It contains 59 lysines, 30-35 as primary amines capable of reacting with conjugation sites of linkers. It is a popular carrier for weakly antigenic compounds. BSA can be used to block nonspecific binding sites in many immunochemical experiments such as ELISA, immunoblotting and immunohistochemical studies. It may be used as a non-relevant protein in enzyme immunoassays.

    The KLH cannot be used for this because the anti-KLH antibodies, which formed during immunization, will interfere with the measurement of anti-heptan antibodies. When KLH is used as the carrier, heptan-BSA conjugates can be used because they do not interfere with the measurement for anti-heptan antibodies.

  • What is the length of the peptides Biopeptek can synthesize?
  • Biopeptek routinely peptide synthesis of 3 - 50 amino acids in length. We can also synthesize peptides of greater than 100 amino acids in length. The minimum length of synthetic peptides should not be less than 3 amino acids. For shorter custom peptide sequences, cleavage from the synthesis resin and following purification can be problematic.
  • Do I need Amino Acid Sequencing?
  • Solid phase peptide synthesis is carried out under a controlled and calculated environment. There are very few occasions that the synthetic peptide sequence is in question. By using a mass spec analysis, you can determine the molecular weight of the synthetic peptide, thus proving the sequence completion of the peptide synthesis. However, there are cases where peptide sequencing is something we recommend, such as with MAPS peptides. With the majority of MAPS peptides, the mass spec analysis provides inconclusive information, because of the nature of MAPS peptides. Sequencing can be an easy alternative for proof of peptide synthesis completion, and affirmation of peptide sequence in publication use.
  • What is PEGylation and how do I use it?
  • Polyethylene glycol (PEG) is a useful delivery system for custom peptide and protein-based biopharmaceuticals. PEGylation is the chemical attachment of PEG to a custom peptide on a specified site of the molecule. Studies have shown an increase in the potential bioavailability of custom peptides when incorporating PEG into synthetic peptide sequences versus the injection of a naked peptide. Drug oriented custom peptides show significant improvement to their therapeutic properties, including better patient compliance and side effect profile.
了解更多信息,請通過[email protected]或者電話(0532) 55676230聯系我們。我們期待能給您帶來幫助。