酶標(biāo)記物工作濃度的選擇
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">酶標(biāo)記物包括酶標(biāo)記抗原、酶標(biāo)記抗體和酶標(biāo)記</font>SPA<font face="宋體">等。酶標(biāo)記物質(zhì)量的好壞直接關(guān)系到免疫酶技術(shù)的成功與否,因此被稱為關(guān)鍵的試劑。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">酶標(biāo)記物中常用的是酶標(biāo)記抗體,它是將酶與特異性抗體經(jīng)適當(dāng)方法連接而成。酶標(biāo)記抗體的質(zhì)量主要取決于純度好、活性強(qiáng)及親和力高的酶和抗體,其次要有良好的制備方法。</span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">目前,高質(zhì)量的酶</font>(<font face="宋體">如辣根過氧化物酶,簡稱</font><font face="Calibri">HRP)</font><font face="宋體">國內(nèi)已有商品供應(yīng)。高質(zhì)量的抗體則可通過提取純化而獲得。在制備方法上,宜選用產(chǎn)率高、不影響結(jié)合物的活性和不混雜干擾性物質(zhì)且操作簡便易行的方法。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="background-color: rgb(255, 255, 0);"><span style="color: rgb(255, 0, 0);"><strong><span style="font-family: 宋體; font-size: 9pt;">酶聯(lián)生物</span><span style="font-family: 宋體; font-size: 9pt;">酶標(biāo)記物工作濃度的選擇</span></strong></span></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">在免疫酶技術(shù)中,首先要確定的變異因素就是酶標(biāo)記物的工作濃度。因?yàn)槊笜?biāo)記物濃度的很小變化,便可導(dǎo)致試驗(yàn)結(jié)果產(chǎn)生很大的波動。另外,由于濃度過高,可使非特異性反應(yīng)增加,而濃度過低又可影響測定的敏感性。因此,正式試驗(yàn)前必須準(zhǔn)確滴定其工作濃度。</span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">酶標(biāo)記抗體的滴定方法是:將抗原</font>(<font face="宋體">或抗體</font><font face="Calibri">)</font><font face="宋體">物理吸附于固相載體上,然后將經(jīng)過一系列稀釋的酶標(biāo)抗體</font><font face="Calibri">(</font><font face="宋體">或抗</font><font face="Calibri">Ig</font><font face="宋體">抗體</font><font face="Calibri">)</font><font face="宋體">與吸附在載體上的抗原</font><font face="Calibri">(</font><font face="宋體">或抗體</font><font face="Calibri">)</font><font face="宋體">起反應(yīng),以酶與底物的顯色反應(yīng)程度來確定酶標(biāo)記抗體的效價,或稱工作濃度。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color: rgb(255, 0, 0);"><strong><span style="font-family: 宋體; font-size: 9pt;">其步驟為:</span></strong></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">先將抗原</font>(<font face="宋體">或抗體</font><font face="Calibri">)</font><font face="宋體">用</font><font face="Calibri">0.05M PH9.6</font><font face="宋體">包被緩沖液稀釋為</font><font face="Calibri">10</font><font face="宋體">μ</font><font face="Calibri">g</font><font face="宋體">/</font><font face="Calibri">ml</font><font face="宋體">左右,于聚苯乙烯板孔內(nèi)加</font><font face="Calibri">0.1ml</font><font face="宋體">,</font><font face="Calibri">4</font><font face="宋體">℃過夜,次日以洗滌緩沖液洗滌</font><font face="Calibri">3</font><font face="宋體">次。酶標(biāo)記抗體用</font><font face="Calibri">1</font><font face="宋體">%</font><font face="Calibri">BSA-PBS</font><font face="宋體">液依次稀釋成</font><font face="Calibri">1</font><font face="宋體">∶</font><font face="Calibri">100</font><font face="宋體">,</font><font face="Calibri">1</font><font face="宋體">∶</font><font face="Calibri">200</font><font face="宋體">,</font><font face="Calibri">1</font><font face="宋體">∶</font><font face="Calibri">400</font><font face="宋體">,</font><font face="Calibri">1</font><font face="宋體">∶</font><font face="Calibri">800</font><font face="宋體">,</font><font face="Calibri">1</font><font face="宋體">∶</font><font face="Calibri">1600</font><font face="宋體">……</font><font face="Calibri">(</font><font face="宋體">根據(jù)據(jù)抗體的滴度而定</font><font face="Calibri">)</font><font face="宋體">,分別加入反應(yīng)孔中,每個稀釋度二孔,每孔</font><font face="Calibri">0.1ml</font><font face="宋體">,</font><font face="Calibri">37</font><font face="宋體">℃孵育</font><font face="Calibri">1</font><font face="宋體">小時后洗滌。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">然后加底物液,每孔</font>0.1ml<font face="宋體">,</font><font face="Calibri">37</font><font face="宋體">℃</font><font face="Calibri">10</font><font face="宋體">~</font><font face="Calibri">30</font><font face="宋體">分鐘。以</font><font face="Calibri">2M H</font><font face="宋體">2</font><font face="Calibri">SO</font><font face="宋體">4</font><font face="Calibri">0.05ml</font><font face="宋體">終止反應(yīng)。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">結(jié)果判定主要以</font>ELISA<font face="宋體">比色儀讀取各孔</font><font face="Calibri">OD</font><font face="宋體">值。并以</font><font face="Calibri">OD</font><font face="宋體">為縱座標(biāo),結(jié)合物濃度為橫座標(biāo),繪制滴定曲線。由曲線上查得</font><font face="Calibri">OD</font><font face="宋體">值為</font><font face="Calibri">1.0</font><font face="宋體">左右,且曲線斜率時的酶標(biāo)抗體稀釋度,即為該標(biāo)記物的工作濃度。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color: rgb(255, 0, 0);"><strong><span style="font-family: 宋體; font-size: 9pt;"><font face="宋體">有關(guān)試驗(yàn)的試劑及器材均見</font>ELISA<font face="宋體">部分:</font></span></strong></span></p>
<p class="MsoNormal"><span style="font-size: 9pt;"><font face="宋體" style="font-family: 宋體;">要說明的是,本法為</font><font face="宋體" style="font-family: 宋體;">ELISA直接法,所測的工作濃度與在實(shí)際應(yīng)用中的</font><font face="宋體" style="font-family: 宋體;">適濃度可相差幾個滴度。這就要求在建立</font><font face="Calibri" style="font-family: 宋體;">ELISA</font><font face="宋體" style="font-family: 宋體;">實(shí)驗(yàn)系統(tǒng)中,因此基礎(chǔ)上還應(yīng)進(jìn)一步確定實(shí)際工作濃度</font><font face="Calibri" style="font-family: 宋體;">(</font><font face="宋體" style="font-family: 宋體;">可采用方陣法</font><font face="Calibri" style="font-family: 宋體;">)</font><font face="宋體" style="font-family: 宋體;">,以達(dá)到</font><font style="" face="Calibri">合</font><font face="宋體" style="font-family: 宋體;">適的實(shí)驗(yàn)條件。歡迎來電咨詢具體關(guān)于酶標(biāo)記物動態(tài)。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>