PMA-Lite LED 光解儀 PMA-Lite LED Photolysis
PMA-Lite LED 光解儀是一種輕質 LED輻照設備,設計用于在活性 PCR 應用中對PMAxx? 或PMA 處理的樣品進行佳光解。
PMA-Lite LED 光解儀特征
多可容納 18 個樣品瓶(1.5-2 mL 大?。?/p>
多個藍色 LED 為樣品瓶的側面和底部提供均勻照明
內置風扇,保持溫度≤37°C
用于 10、15、20 或 30 分鐘光解的計時器
包括通用插座適配器,適用于北美以外的客戶
自購買之日起兩年保修
規格
尺寸(寬 x 深 x 高):8.25 x 6.25 x 2.625 英寸(21 x 15.9 x 6.7 厘米)
重量:3 磅 10.7 盎司(1.66 千克)
頻率范圍:50~60 Hz
功率范圍:100~240 VAC
內部 120/240 V 轉換器
大功率: 60 W
LED輸出波長:465-475 nm
活性聚合酶鏈反應
活性PCR是一種強大的技術,用于靈敏和快速地檢測活微生物。與耗時的培養方法不同,qPCR 是一種快速靈敏的檢測方法。然而,正常的qPCR不能區分活細胞和死細胞。使用 PMAxx? 或 PMA 的 v-PCR,您可以獲得 PCR 的速度、靈敏度和特異性,以及可量化的活力。由于無需培養,您甚至可以檢測活菌但不可培養 (VBNC) 細菌。v-PCR 技術不僅可以應用于細菌,還可以應用于酵母、病毒、真核生物和古細菌等其他生物。
E90002 PMA-Lite LED Photolysis Device
美國Biotium Inc是熒光標記技術的染料廠家,其產品被科學家廣泛用于生物化學,免疫學,細胞生物學和分子生物學,新藥篩選等領域。該公司產品GelRed 和GelGreen核酸染料(EB和SYBR染料的替代者)已經在國內被廣泛使用。EvaGreen PCR染料、CF系類和Mix-n-stain抗體標記染料、NucView Caspase 3/7 底物和PMA 活細胞檢測試劑等一系列標志性的熒光染料,都是該公司的拳頭產品。 作為Biotium Inc 在中國的合作伙伴,我們負責該公司產品的國內的市場銷售與技術指導工作。
如何能夠高效靈敏的檢測死細菌中存在的活細菌數量在實際應用中至關重要,包括食品安全檢查,飲用水質量控制和藥物診斷等。而傳統使用的細菌培養的檢測方法,既費時又不夠靈敏。
以PCR為基礎的替代檢測方法具有快速和高靈敏度特點。然而,基于 PCR的檢測方法并不能有效的將活細胞和死細胞區分開來。近年來,Biotium公司研發的新型DNA修飾染料-疊氮碘化丙錠 (PMA?) 成功的克服了該難題。
PMA? 是一種與DNA具有高度親和性的光反應染料。該染料可以嵌入在雙鏈DNA中,當暴露在強烈的可見光下時可以與DNA形成共價連接,從而實現對DNA的化學修飾。而經修飾后的DNA將不能通過PCR進行擴增 (Figure 1)。 由于PMA? 被設計為不能被細胞膜穿透性,因此當使用該染料處理同時包含死細菌和活性菌的樣品時,只有細胞膜結構受到破壞的死細菌中的DNA能夠被化學修飾。接下來可以進一步裂解活性菌并進行qPCR檢測,從而實現對活性菌的選擇性檢測。同時,PMA?-PCR技術不僅能夠應用于細菌檢測,同樣也可以用于其他微生物的檢測(詳見PMA? 應用列表)。
PMAxx?是一款Biotium公司研發的用于Viability PCR檢測的DNA修飾染料,是PMA?的升級版。和PMA? 染料一樣,PMAxx?也是一款能夠和dsDNA高度親和的光反應染料。 在可見光下一經光解,PMAxx?能夠與dsDNA共價結合,從而修飾DNA使其不能被PCR擴增。PMAxx?也被設計為不具備細胞膜穿透性,因此在檢測包含死細菌和活性菌的細胞群體時,僅能夠選擇性地修飾死細胞中因細胞膜不完整而暴露的DNA,而擁有完整細胞膜的活細胞中DNA不能被修飾。PMAxx?染料的這個特性使其在通過qPCR選擇性檢測活性菌時非常有用。
PMAxx?作為PMA?的替代升級產品,具有更高的靈敏性。盡管PMA能夠通過qPCR有效的區分死細菌和活性菌,但并不能夠*排除來自死細胞DNA的PCR產物,從而帶來潛在的假陽性結果。作為Biotium公司的新型染料,PMAxx?能夠更加高效的抑制死細胞中DNA的PCR擴增,從而更好的區分死細菌和活性菌。
PMA? Enhancer能夠有效地改善通過PMA?來區分革蘭氏陰性菌中死細菌和活性菌。我們提供的PMA? Enhancer為5倍濃縮液,可在使用PMA?之前添加到樣品中。當對經過Enhancer預處理過的革蘭氏陰性菌中的 進行PCR檢測時,樣品中死細胞的信號明顯減弱,而活細胞的信號則沒有變化。PMA? Enhancer也可以與PMAxx?作為搭配使用。因此,同時使用PMA? 和PMA? Enhancer可以有效的對革蘭氏陰性菌進行viability PCR檢測。 PMA? Enhancer作為一個獨立的產品提供。另外,在PMA Bacterial Viability Kits(革蘭氏陰性菌)中也包含該產品。
The PMA-Lite? LED Photolysis Device is a light-weight LED light box designed for optimal photolysis of PMAxx?– or PMA-treated samples in viability PCR applications. Each purchase of PMA-Lite? Photolysis Device includes a free trial size of PMAxx?.
Features
Holds up to 18 vials (1.5-2 mL size)
Multiple blue LEDs provide even illumination to the sides and bottoms of all vials
Internal fan to maintain temperature ≤37°C
Timer for 10, 15, 20 or 30 minutes of photolysis
Universal outlet adapter included for customers outside North America
Two-year warranty from date of purchase
Specifications
Dimensions (W x D x H): 8.25 x 6.25 x 2.625 in. (21 x 15.9 x 6.7 cm)
Weight: 3 lb. 10.7 oz. (1.66 kg)
Frequency Range: 50~60 Hz
Power Range: 100~240 VAC
Internal 120/240 V converter
Maximum Power: 60 W
LED Output Wavelength: 465-475 nm
Viability PCR
Viability PCR is a powerful technology for the sensitive and rapid detection of viable microorganisms. Unlike time-consuming culturing methods, qPCR is a fast and sensitive method of detection. However, normal qPCR does not distinguish between live and dead cells. With v-PCR using PMAxx? or PMA, you get the speed, sensitivity and specificity of PCR, plus quantifiable viability. And because no culturing is required, you can even detect viable but not culturable (VBNC) bacteria. The v-PCR technology can be applied not only to bacteria but to other organisms like yeast, viruses, eukaryotes, and archaea.
Biotium offers the PMA-Lite? LED Photolysis Device for light-induced cross-linking of PMAxx? and PMA to dsDNA. The PMA-Lite? is designed for samples in microcentrifuge tubes.
Commercial halogen lamps (>600 W) for home use have been employed for photoactivating PMA in some publications, though results may be less consistent due to variation in the set-up configurations. If you decide to use a halogen lamp, place the tubes on a block of ice on a rocking platform to ensure continuous mixing. We recommend freezing water in a clear tray to make the ice block, and placing a piece of aluminum foil under the tray to reflect light upward toward the bottom of the tubes. Set the lamp 20 cm above the samples, so that the light source is pointing downward onto the samples (up to 45° downward slant is OK). Expose samples to light for 5-15 min while rocking.
Each tube position on the PMA-Lite? is illuminated by the three LED bulbs. We haven’t tested positional variability, but it is likely that the illumination varies slightly between positions and between devices. However, the illumination at each position is exceedingly bright, far in excess to what is required for photocrosslinking of the viability dyes EMA, PMA or PMAxx? to nucleic acids, so any variability should not significantly affect the vPCR results.
The LEDs in PMA-Lite have brightness of 600-800 millicandela (mcd). There are three LEDs next to each tube (one bottom, two side) and the wavelength is 465-475 nm.