As pharmaceutical microbiology continues to evolve under tighter regulatory expectations and advancing technologies, manual microbiological testing methods remain a critical area of focus, including many aspects of the environmental monitoring (EM) workflow. From surface sampling to plate counting, many tasks remain manual, not due to a lack of innovation but because methods like applying a contact plate to a surface remain the most practical way to detect microbes in open manufacturing environments. Furthermore, EM responsibilities are often assigned to early-career or newly hired personnel, which can limit the practical insight needed to master the nuanced techniques and decision-making that come with experience. While environmental monitoring workflows remain essential for understanding contamination control of classified environments, they continue to carry a persistent challenge for microbiologists: inconsistency. Variability introduced by human technique and error can result in under-detected contamination, misleading trend data, and potential regulatory concerns.
隨著制藥微生物學在更嚴格的監(jiān)管期望和不斷進步的技術(shù)下不斷發(fā)展，手動微生物檢測方法仍然是一個關(guān)鍵的重點領(lǐng)域，包括環(huán)境監(jiān)測 （EM） 工作流程的許多方面。從表面采樣到平板計數(shù)，許多任務(wù)仍然是手動的，不是因為缺乏創(chuàng)新，而是因為在表面應(yīng)用接觸板等方法仍然是在開放式制造環(huán)境中檢測微生物的最實用方法。此外，EM 職責通常分配給處于職業(yè)生涯早期或新雇用的人員，這可能會限制掌握經(jīng)驗帶來的細微技術(shù)和決策所需的實際洞察力。雖然環(huán)境監(jiān)測工作流程對于了解分類環(huán)境的污染控制仍然至關(guān)重要，但它們?nèi)匀唤o微生物學家?guī)砹艘粋€持續(xù)的挑戰(zhàn)：不一致。人為技術(shù)和錯誤引入的可變性可能導(dǎo)致污染檢測不足、趨勢數(shù)據(jù)誤導(dǎo)和潛在的監(jiān)管問題。

To improve consistency and detection in environmental monitoring, the industry has explored alternative technologies, such as Biofluorescent Particle Counters (BFPCs)(1) and integrated digital workflows, that aim to reduce reliance on manual methods. While these innovations offer promising advancements (2) for air sampling methods, traditional surface sampling remains widely used and continues to present its own challenges. Unlike equipment-based methods such as viable air samplers and particle counters, which incorporate built-in calibration and performance qualification steps, surface sampling lacks the same level of standardization. This is especially significant given that these manual techniques are often used to assess critical product-contact surfaces under Grade A conditions at the end of aseptic filling processes. Ensuring reliable results will continue to depend on well-trained, qualified personnel who understand both the method and the implications of the data it generates.
為了提高環(huán)境監(jiān)測的一致性和檢測能力，該行業(yè)已經(jīng)探索了替代技術(shù)，例如生物熒光粒子計數(shù)器 （BFPC）和集成數(shù)字工作流程，旨在減少對手動方法的依賴。雖然這些創(chuàng)新為空氣采樣方法提供了有希望的進步 ， 但傳統(tǒng)的表面采樣仍然被廣泛使用，并繼續(xù)帶來其自身的挑戰(zhàn)。與基于設(shè)備的方法（如可行的空氣采樣器和粒子計數(shù)器）不同，表面采樣缺乏相同級別的標準化。鑒于這些手動技術(shù)通常用于在無菌灌裝過程結(jié)束時評估 A 級條件下的關(guān)鍵產(chǎn)品接觸表面，這一點尤為重要。確?？煽康慕Y(jié)果將繼續(xù)取決于訓練有素的合格人員，他們了解該方法及其所生成數(shù)據(jù)的含義。

So, how do we reduce variability and improve confidence in these foundational, manual, technique-dependent practices? This article explores that question by further examining the role of surface sampling in environmental monitoring and its place within the broader contamination control strategy. Then, we will take a closer look at how recovery efficiency (3) is measured, the factors that influence it, and how it applies to both contact and swab surface sampling methodologies. The discussion will include the regulatory and contamination control aspects of recovery efficiency, particularly in light of updated expectations outlined in EU GMP Annex 1 (4). We will then review data from several recent studies that shed light on current challenges and areas for improvement in surface sampling. Finally, the article will consider how the pharmaceutical and compounding industries can move forward through standardization, structured training, and qualification of personnel to ensure consistent, reliable performance of microbial surface sampling.
那么，我們?nèi)绾螠p少可變性并提高對這些基礎(chǔ)的、手動的、依賴于技術(shù)的實踐的信心呢？本文通過進一步研究表面采樣在環(huán)境監(jiān)測中的作用及其在更廣泛的污染控制策略中的地位來探討這個問題。然后，我們將仔細研究如何測量回收效率 ， 影響回收效率的因素，以及它如何應(yīng)用于接觸式和拭子表面采樣方法。討論將包括回收效率的監(jiān)管和污染控制方面，特別是考慮到歐盟 GMP 附錄 1  中概述的最新期望。然后，我們將回顧最近幾項研究的數(shù)據(jù)，這些數(shù)據(jù)闡明了表面采樣的當前挑戰(zhàn)和需要改進的領(lǐng)域。最后，本文將考慮制藥和復(fù)合行業(yè)如何通過標準化、結(jié)構(gòu)化培訓和人員資格認證來向前發(fā)展，以確保微生物表面采樣的一致、可靠性能。

The Role of Surface Sampling in Environmental Monitoring
表面采樣在環(huán)境監(jiān)測中的作用

Surface sampling is a foundational element of environmental monitoring programs in pharmaceutical manufacturing, playing a key role in ensuring the detection and control of classified environments. Two of the most common methods used for surface sampling are contact plating and swabbing, each with specific applications and limitations. Contact plates are typically used for smooth, flat, non-porous surfaces such as glass and stainless steel and building materials such as ceilings, floors, and doors. When applied correctly, either rolled or pressed with consistent pressure, they offer relatively high recovery efficiency and are straightforward to use. Swabs, on the other hand, are more commonly used when sampling irregular, textured, or hard-to-reach surfaces where contact plates cannot make adequate contact. These locations also tend to be product contacting, in the case of needles or stopper hopper bowls for traditional aseptic filling or tubing port connections for manual ATMP filling. However, swabbing introduces additional downstream variability due to its more complex workflow, which includes moistening the swab, applying a consistent technique, ensuring adequate surface area, and performing secondary processing steps to extract microbes before incubation.
表面采樣是制藥生產(chǎn)環(huán)境監(jiān)測程序的基本組成部分，在確保受控環(huán)境的檢測與控制方面發(fā)揮關(guān)鍵作用。表面采樣最常用的兩種方法是接觸平板法和拭子法，每種方法都有特定的應(yīng)用場景和局限性。接觸平板法通常用于光滑、平整的無孔表面，如玻璃、不銹鋼等材質(zhì)，以及天花板、地板和門等建筑材料表面。若操作得當——無論是以均勻壓力滾動還是按壓平板——該方法可實現(xiàn)較高的微生物回收率，且使用簡便。拭子法則更適用于采樣不規(guī)則、有紋理或難以觸及的表面，這些位置通常是接觸產(chǎn)品的部位（例如傳統(tǒng)無菌灌裝中的針頭或膠塞料斗碗，或手動ATMP灌裝中的管道接口），接觸平板法難以在這些表面充分貼合。然而，由于拭子法工作流程更復(fù)雜，會引入更多下游變異性，具體包括：濕潤拭子、采用一致的擦拭技術(shù)、確保足夠的采樣面積，以及在培養(yǎng)前執(zhí)行提取微生物的二次處理步驟等。

Each surface sampling method presents its own set of challenges. Recovery rates can vary significantly based on the type of surface sampled, the material of the swab or plate, and, critically, the technique of the individual performing the sampling. Manual variability in pressure, duration, and contact area can all influence the reliability of results. Despite these known limitations, the data obtained from surface sampling is often used to support the release of batch-related materials across a wide range of pharmaceutical operations, from aseptic manufacturing to advanced modalities such as cell and gene therapy and sterile compounding. As facilities build more robust Environmental Monitoring Risk Assessments (EMRAs)  to identify critical sampling locations that narrow in on real process impact, ensuring those samples are collected with accuracy and consistency becomes even more important. Manual surface sampling is also likely to remain in use due to its historical significance and alignment with established regulatory standards. The question then becomes not whether to continue performing surface sampling but how confidently we can stand behind the results generated by these manual methods.
每種表面采樣方法都面臨著獨特的挑戰(zhàn)?；厥章士赡芤虿蓸颖砻骖愋?、拭子或平板的材質(zhì)，以及（關(guān)鍵在于）采樣人員的操作技術(shù)而顯著不同。壓力、持續(xù)時間和接觸面積的手動操作變異性，均會影響結(jié)果的可靠性。盡管存在這些已知局限性，但從表面采樣獲得的數(shù)據(jù)仍廣泛用于支持各類制藥操作中批次相關(guān)物料的放行，涵蓋從無菌生產(chǎn)到細胞與基因治療、無菌配制等先進模式。隨著各設(shè)施建立更完善的環(huán)境監(jiān)測風險評估（EMRA）以識別對實際工藝影響較大的關(guān)鍵采樣位置，確保這些樣本采集的準確性和一致性變得更加重要。此外，由于手動表面采樣的歷史重要性及其與既定監(jiān)管標準的契合性，該方法可能會繼續(xù)沿用。    因此，問題的核心不再是是否繼續(xù)進行表面采樣，而是我們對這些手動方法所產(chǎn)生結(jié)果的置信度究竟如何。

Understanding and Measuring Surface Recovery Efficiency
表面回收率的理解與測定

Recovery efficiency is a key concept in evaluating the performance of environmental monitoring (EM) methods, and still, it has not been adequately applied to viable surface monitoring. It refers to the percentage of viable microorganisms that a sampling method can effectively collect from a surface, the air, or personnel and adequately culture for enumeration. In practical terms, it reflects how well a method transfers microbes from the sampled area to the growth medium, allowing the resulting colony counts to be compared to relevant acceptance criteria given the many variables involved. Accurate recovery is critical to ensure that monitoring data genuinely reflects the microbial state of the environment rather than the limitations of the method used to assess it.
回收率是評估環(huán)境監(jiān)測（EM）方法性能的關(guān)鍵概念，但目前仍未充分應(yīng)用于有活力的表面監(jiān)測。它是指采樣方法能夠從表面、空氣或人員中有效收集并通過培養(yǎng)進行計數(shù)的存活微生物百分比。    在實際應(yīng)用中，回收率反映了一種方法將微生物從采樣區(qū)域轉(zhuǎn)移到培養(yǎng)基的能力，考慮到諸多相關(guān)變量，這使得所得菌落計數(shù)可與相應(yīng)的合格標準進行比較。準確的回收率至關(guān)重要，它確保監(jiān)測數(shù)據(jù)真實反映環(huán)境的微生物狀態(tài)，而非用于評估的方法本身存在局限性。

Regulatory expectations have placed increasing emphasis on recovery efficiency, particularly in the revised EU GMP Annex 1, where the expectations are clear in stating that sampling methods and equipment must be fully understood and that supporting data on recovery efficiency must be available. This notion also aligns with USP General Chapters <1115> Bioburden Control of Nonsterile Drug Substances and Products and <1116> Microbiological Control and Monitoring of Aseptic Processing Environments , which emphasize the need for scientifically sound EM programs and a deep understanding of both contamination risks and the performance characteristics of monitoring tools. For sterile compounding, USP <797> Pharmaceutical Compounding—Sterile Preparations reinforces that individuals involved in cleanroom operations, including those performing sampling activities, must demonstrate initial and ongoing viable surface sampling competency. Together, these guidances push the industry toward not only justifying method selection but also validating the effectiveness of those methods in real-world use to ensure that their sampling methods can consistently detect contamination and that these methods are applied in a controlled and qualified manner. Data integrity can become compromised when recovery efficiency is very low, inconsistent, or poorly understood. This can result in either false negatives, where microbial contamination goes undetected, or false positives due to poor sampling techniques or handling, which may trigger unnecessary investigations or render certain classified areas no longer fit for processing.
監(jiān)管層面對回收率的重視程度與日俱增，尤其是在經(jīng)修訂的《歐盟GMP附件1》中明確要求：必須充分了解采樣方法和設(shè)備，且必須提供回收率相關(guān)的支持數(shù)據(jù)。這一理念也與《美國藥典》（USP）通則<1115>《非無菌原料藥和產(chǎn)品的生物負荷控制》及<1116>《無菌工藝環(huán)境的微生物控制與監(jiān)測》一致，這些通則強調(diào)環(huán)境監(jiān)測（EM）程序需具備科學合理性，同時需深入理解污染風險和監(jiān)測工具的性能特征。對于無菌配制操作，USP<797>《藥品配制—無菌制劑》進一步強調(diào)：參與潔凈室操作的人員（包括執(zhí)行采樣任務(wù)的人員）必須證明其在有活力表面采樣方面的初始能力和持續(xù)能力?？傮w而言，這些指南推動行業(yè)不僅要證明方法選擇的合理性，還要驗證這些方法在實際應(yīng)用中的有效性，以確保采樣方法能夠持續(xù)檢測到污染，并且這些方法以受控且合格的方式應(yīng)用。當回收率極低、不穩(wěn)定或未被充分理解時，數(shù)據(jù)完整性可能受到損害。這可能導(dǎo)致兩種后果：一是假陰性（微生物污染未被檢測到），二是因采樣技術(shù)或操作不當導(dǎo)致的假陽性（可能引發(fā)不必要的調(diào)查，或使某些潔凈區(qū)域不再適合生產(chǎn)操作）。

Different sampling methods also provide different levels of recovery efficiency. For surface sampling, contact plates typically offer higher recovery from flat, non-porous surfaces, while swabs are necessary for irregular or hard-to-reach areas but often yield lower and more variable recovery. Proper aseptic technique, especially by the analyst performing the sampling, is vital to ensure consistency and reduce contamination or false results. Air sampling methods such as impactors depend on factors like airflow rate and sampler design to capture viable particles efficiently, whereas settling plates, being passive, tend to have much lower and less predictable recovery, if any (9). Personnel monitoring, often conducted via glove or garment sampling with contact plates, also has its limitations, especially on certain fabrics where microbes may actually be trapped or embedded and thus hinder recovery.
不同的采樣方法也會帶來不同水平的回收率。對于表面采樣，接觸平板通常能從平整無孔的表面獲得更高的回收率，而拭子則適用于不規(guī)則或難以觸及的區(qū)域，但往往回收率更低且變異性更大。恰當?shù)臒o菌操作技術(shù)（尤其是采樣人員的操作）對于確保結(jié)果一致性、減少污染或假陽性結(jié)果至關(guān)重要。   

 空氣采樣方法（如撞擊式采樣器）依賴氣流速率和采樣器設(shè)計等因素來有效捕獲有活力的顆粒，而沉降平板作為被動采樣工具，其回收率通常極低且難以預(yù)測（甚至可能無法有效回收）。人員監(jiān)測（通常通過接觸平板對手套或工作服采樣）也存在局限性，尤其是在某些織物表面，微生物可能實際被截留或嵌入纖維中，從而影響回收率。

Recovery efficiency can be influenced by a range of factors. The physical properties of the surface being sampled, whether smooth, like stainless steel, or porous, like certain plastics, can impact how easily microorganisms are liberated during sampling. Microbial characteristics also play a role; for example, certain organisms may adhere more tightly to surfaces while others may evade capture altogether. The sampling technique itself is another major variable, including how well the contact plate method is applied to the surface, as well as characteristics of swabs such as tip material and moisture content. Post-sampling steps, including incubation conditions and the analyst’s ability to visually detect and enumerate colonies, also affect the final result as well. Most of the variables for surface sampling rely on manual technique, and experience-based methods throughout the entire workflow.
回收率可能受到一系列因素的影響。采樣表面的物理特性（如不銹鋼般光滑，或如某些塑料般多孔）會影響采樣過程中微生物脫離表面的難易程度。微生物特性同樣發(fā)揮作用：例如，某些微生物可能更緊密地附著于表面，而另一些可能完全逃避捕獲。   

 采樣技術(shù)本身是另一個主要變量，包括接觸平板法在表面的應(yīng)用效果，以及拭子的特性（如拭頭材質(zhì)和含水量）。采樣后的步驟（包括培養(yǎng)條件和分析人員目測檢測及計數(shù)菌落的能力）也會影響最終結(jié)果。   

 表面采樣的大多數(shù)變量依賴于手動操作技術(shù)和整個工作流程中基于經(jīng)驗的方法。

Recovery efficiency is not just a technical parameter, as it has direct implications for a facility’s contamination control strategy, too. Low-efficiency methods may lead to an underestimation of microbial risks, affecting the ability to identify probable root causes during investigations or recognize trends that may require action. Overconfidence in a method’s performance or the dataset it provides, without a full appreciation of its limitations or proper controls in place, can erode the foundation of a site’s environmental monitoring program. This is especially important when certain EM results could inform critical product safety or batch release decisions.
回收率不僅是一個技術(shù)參數(shù)，它對生產(chǎn)設(shè)施的污染控制策略也有直接影響。低效的采樣方法可能導(dǎo)致微生物風險被低估，影響調(diào)查期間識別潛在根本原因的能力，或無法察覺需要采取措施的趨勢。   

 在未充分了解方法局限性或未實施適當控制的情況下，對方法性能或其提供的數(shù)據(jù)集過度自信，會削弱生產(chǎn)場地環(huán)境監(jiān)測程序的基礎(chǔ)。當某些環(huán)境監(jiān)測結(jié)果可能為關(guān)鍵產(chǎn)品安全或批次放行決策提供依據(jù)時，這一點尤為重要。

Understanding recovery efficiency is not limited to optimizing one methodology over another; rather, it’s about ensuring that the data collected is meaningful and supports robust contamination control. This requires both method validation and vigilance regarding how surface sampling is executed, interpreted, and incorporated into the overall process and product quality.
理解回收率不僅限于在不同方法間優(yōu)化選擇，更在于確保所收集的數(shù)據(jù)具有實際意義，并為強有力的污染控制提供支持。這需要同時做到方法驗證，以及對表面采樣的執(zhí)行、解讀和其融入整體工藝及產(chǎn)品質(zhì)量的方式保持高度審慎。

Recent Studies on Microbial Surface Sampling Efficiency
微生物表面采樣效率的近期研究

Recent research from pharmaceutical microbiology labs and various companies has provided valuable insights into the factors influencing microbial recovery efficiency in surface sampling, emphasizing the critical roles of sampling techniques, personnel training, and material selection. Four recent studies are discussed below, each determining recovery efficiency using slightly different approaches tailored to their specific study objectives. Currently, no universally adopted method for calculating recovery efficiency across the industry exists, and the results may not be directly comparable. However, collectively, they illustrate that recovery efficiency is influenced by multiple variables.
制藥微生物實驗室和多家公司的最新研究為影響表面采樣中微生物回收效率的因素提供了有價值的見解，強調(diào)了采樣技術(shù)、人員培訓和材料選擇的關(guān)鍵作用。以下討論四項近期研究，每項研究均采用根據(jù)其特定研究目標量身定制的略有不同的方法來確定回收效率。目前，行業(yè)內(nèi)尚未存在普遍采用的計算回收效率的方法，且結(jié)果可能無法直接比較。然而，總體而言，這些研究表明回收效率受多個變量影響。

First, AstraZeneca’s investigation into 55 mm contact plate sampling methodologies demonstrated the influence of application technique on microbial recovery. In the study “Evaluation of Three Different Contact Plate Methods for Microbial Surface Sampling of Naturally Occurring Human Borne Microbial Contamination”, researchers evaluated three manual methods using tryptic soy agar (TSA) contact plates by rolling the plate over the surface for one second, rolling the plate for five seconds, and a firm, direct press application. The findings indicated that both rolling techniques outperformed the single press, yielding average recovery efficiencies of 53% and 48% for the 1-second and 5-second rolls, respectively. While the single firm press produced a significantly lower efficiency of just 16%, it was thought to be a result of reduced overall contacted surface area. The study calculated recovery efficiency by performing two consecutive samples on the same surface. Efficiency was determined by comparing the microbial count from the second (B) sample to the first (A), using the formula: Recovery (%) = [1 – (B / A)] × 100, where a lower second count indicates higher recovery. This study reinforces the importance of technique standardization and suggests that the physical method of sample collection directly affects its ability to capture microbes.
首先，阿斯利康（AstraZeneca）針對55毫米接觸平板采樣方法的研究揭示了操作技術(shù)對微生物回收效率的影響。在《三種不同接觸平板法對自然存在的人體源性微生物污染表面采樣的評估》這一研究中，研究人員使用胰酪大豆瓊脂（TSA）接觸平板評估了三種手動操作方法：將平板在表面滾動1秒、滾動5秒以及用力直接按壓。結(jié)果表明，兩種滾動技術(shù)的效果均優(yōu)于單次按壓-1秒滾動和5秒滾動的平均回收效率分別為53%和48%，而單次用力按壓的效率顯著較低，僅為16%，這被認為是總體接觸表面積減少所致。   

 該研究通過在同一表面進行兩次連續(xù)采樣來計算回收效率，具體方法是將第二次采樣（B）與第一次采樣（A）的微生物計數(shù)進行比較，使用公式：回收率（%）=[1–(B/A)]×100，其中第二次計數(shù)越低表明回收率越高。這項研究強調(diào)了操作技術(shù)標準化的重要性，并表明樣本采集的物理方式直接影響其捕獲微生物的能力。

A second study  performed by the same group, titled “To Determine the Microbial Recovery from Different Surfaces Using a Standard Contact Plate Sampling Method” investigated microbial recovery from various cleanroom surfaces using the 1-second rolling contact plate technique. The surfaces examined included stainless steel, polyester garments, latex, and EPDM, which are all materials found and routinely sampled in pharmaceutical cleanroom environments. The study showed that surface characteristics such as texture and finish may play a role in microbial recovery rates, with smooth, non-porous surfaces like stainless steel and copolyester goggles yielded a higher recovery rate of ~80% when compared to less smooth materials such as garments and gloves that yielded a recovery rate of ~70%. Recovery efficiency in this study was calculated using the same method described in the previous AstraZeneca study. This data reinforces the industry’s need to understand not only sampling methods but also how those methods take into consideration the specific surface types to ensure accurate environmental monitoring.
同一研究團隊進行的第二項研究，題為《使用標準接觸平板采樣法測定不同表面的微生物回收率》，采用1秒滾動接觸平板技術(shù)，對制藥潔凈室環(huán)境中常見的不銹鋼、聚酯工作服、乳膠和三元乙丙橡膠（EPDM）等表面的微生物回收率展開了調(diào)查。研究表明，表面紋理和光潔度等特性可能對微生物回收率產(chǎn)生影響：不銹鋼和共聚酯護目鏡等光滑無孔表面的回收率較高，約為80%；而工作服和手套等光滑度較低的材料，回收率約為70%。該研究采用與阿斯利康前一項研究相同的方法計算回收效率。這些數(shù)據(jù)進一步表明，行業(yè)不僅需要了解采樣方法，還需考慮這些方法如何針對特定表面類型進行調(diào)整，以確保環(huán)境監(jiān)測結(jié)果的準確性。

Figure 1 Contact Plate % Recovery by Participant Sampling Event
圖 1 按采樣人員劃分的接觸平板回收率百分比（采樣事件）

Next, a study assessing the influence of proper training and techniques for contact plate sampling was explored in a multi-year study  conducted by Stratix Labs (a USP company). This study assessed approximately 1,155 individual participant sampling events across the industry using 55 mm contact plates on standardized test surfaces that were precoated with a specific quantity of viable microbes. In this study, each individual data point represented an average of three replicate microbial-coated samples, and a 20% recovery efficiency threshold was used as a benchmark value. In this study, the recovery efficiency was calculated as the number of microbes recovered on the contact plate divided by the total number on the surface. This study demonstrated significant variability in recovery efficiency across participants. While some consistently achieved high recoveries above 60–80%, other participants fell below 20%, and some even approached 0% recovery (Figure 1). The observed variation is most likely attributable to human factors, such as inconsistent pressure, variation in contact time, lack of rolling motion, and overall, poor aseptic technique. In addition, and importantly, the sampling device used and the human factors of the individual combine to create the ‘sampling system’ that directly influences the recovery efficiency for viable surface sampling. These findings point to the critical importance of analyst training and qualification, technique consistency, and ongoing competency assessment to ensure the integrity of environmental monitoring data.
接下來，在 Stratix Labs（一家 USP 公司）進行的一項多年研究 中探討了評估適當培訓和技術(shù)對接觸板采樣的影響的研究。這項研究評估了整個行業(yè)大約 1,155 個個體參與者的采樣事件，使用 55 毫米接觸板在標準測試表面上預(yù)涂有特定數(shù)量的活微生物。在這項研究中，每個單獨的數(shù)據(jù)點代表平均三個重復(fù)的微生物包被樣品，并使用 20% 的回收效率閾值作為基準值。在本研究中，回收效率的計算方法是在接觸板上回收的微生物數(shù)量除以表面的總數(shù)。這項研究表明，參與者之間的恢復(fù)效率存在顯著差異。雖然一些參與者始終實現(xiàn) 60-80% 以上的高回收率，但其他參與者的回收率低于 20%，有些參與者甚至接近 0% 的回收率 （圖 1）。觀察到的變化很可能是由于人為因素造成的，例如壓力不一致、接觸時間的變化、缺乏滾動運動以及總體上無菌技術(shù)不佳。此外，重要的是，所使用的采樣裝置和個人的人為因素相結(jié)合，形成了直接影響有效表面采樣的回收效率的“采樣系統(tǒng)”。這些發(fā)現(xiàn)指出了分析師培訓和資格認證、技術(shù)一致性和持續(xù)的能力評估對于確保環(huán)境監(jiān)測數(shù)據(jù)的完整性至關(guān)重要。

Beyond contact plates, swabbing is another important surface sampling method to consider, as recovery efficiencies can vary significantly depending on the swab material, sampling technique, and the characteristics of the surface being sampled. A 2024 study published by Kumarajith, et al. (13) evaluated the uptake and release efficiency of four different swab types: cotton, foam, and two flocked designs, including a variety of buffers. Cotton swabs demonstrated the highest uptake efficiency (~96%) but released microbes poorly, often under 50%, and are not permitted in cleanroom environments. Flocked swabs, by contrast, showed strong performance in both uptake (over 80%) and release (over 70%), with overall recovery efficiencies from stainless steel surfaces ranging between 55–80%, depending on the buffer used. Foam swabs were found to have the lowest uptake (~58%) but moderate release capabilities. In this study, overall swab efficiency was calculated by first determining uptake efficiency, based on the difference between the number of cells applied to a surface and the number remaining after swabbing, and release efficiency, measured as the percentage of those cells successfully released from the swab into a buffer. These two components were combined to assess total recovery from stainless steel surfaces using a capillary electrophoresis detection method. These results indicated that the material of the swab significantly impacts recovery efficiency and that method selection must be aligned with surface type and sampling methodology. In addition, industry expert microbiologist Tim Sandle (14) has also commented on the variability of swab performance, emphasizing that even the best-performing flocked swabs typically achieve 50–60% recovery in the field and that technique also remains a major determinant of successful recovery rates.
除接觸平板外，拭子法是另一種需要關(guān)注的重要表面采樣方法，其回收效率可能因拭子材質(zhì)、采樣技術(shù)和采樣表面特性的不同而存在顯著差異。Kumarajith等人2024年發(fā)表的一項研究（13）評估了四種不同類型拭子（棉簽、泡沫拭子和兩種植絨拭子）在多種緩沖液條件下的捕獲效率和釋放效率。結(jié)果顯示： 

 a. 棉簽的捕獲效率最高（約96%），但微生物釋放能力較差（通常低于50%），且不允許在潔凈室環(huán)境中使用；

 b. 植絨拭子在捕獲（超過80%）和釋放（超過70%）兩方面均表現(xiàn)優(yōu)異，在不銹鋼表面的總體回收效率為55%–80%（具體取決于所用緩沖液）； 

 c. 泡沫拭子的捕獲效率最低（約58%），但釋放能力中等。    

該研究中，拭子的總體效率通過以下方式計算：首先基于涂布到表面的菌量與拭子采樣后殘留菌量的差值確定捕獲效率，再通過拭子成功釋放到緩沖液中的菌量占比確定釋放效率，最后結(jié)合這兩個指標、使用毛細管電泳檢測法評估不銹鋼表面的總回收率。結(jié)果表明，拭子材質(zhì)對回收效率有顯著影響，方法選擇必須與表面類型和采樣方式相匹配。此外，行業(yè)微生物專家Tim Sandle（14）也指出拭子性能的變異性，強調(diào)即使性能最佳的植絨拭子在實際應(yīng)用中通常也只能達到50%–60%的回收率，而操作技術(shù)仍是影響回收率的關(guān)鍵因素。

Collectively, these four studies reveal that a combination of surface characteristics, sampling methodologies, and operator proficiency influences microbial recovery efficiency. Addressing these factors through standardized procedures, rigorous training and qualification, and appropriate material selection (in the case of swabs) is essential for obtaining reliable data in environmental monitoring of pharmaceutical cleanroom surfaces.
總體而言，這四項研究表明，表面特性、采樣方法和操作人員熟練程度共同影響著微生物回收效率。在制藥潔凈室表面的環(huán)境監(jiān)測中，通過標準化程序、嚴格的培訓與資質(zhì)認證以及適當?shù)牟牧线x擇（如拭子材質(zhì)）來解決這些因素，是獲取可靠數(shù)據(jù)的關(guān)鍵。

Moving Toward a Standardized and Qualified Approach
邁向標準化和合格化的方法

Inconsistent sampling techniques by unqualified or inadequately trained personnel can introduce variability into environmental monitoring data, potentially affecting the accuracy of contamination control trends. Human sampling errors or failures to follow procedure can include inconsistent pressure, poor timing, or lack of aseptic technique, thus resulting in data that does not reliably reflect environmental conditions. This highlights the criticality of comprehensive training programs that go beyond procedural awareness and focus on building true competency in surface sampling execution and ownership over microbial recovery. The competency must ensure that the analyst understands what they are sampling, the parameters of the test, and how their specific technique can directly influence the outcome of the recovery efficiency. It is in the best interest of all companies to detect actual contamination, should it be present on the surface. Even though this article has narrowed in on surface sampling, the proper handling of culture plates, in general, is also foundational to both viable air sampling and personnel monitoring.
不合格或培訓不足的人員采用不一致的采樣技術(shù)，可能會給環(huán)境監(jiān)測數(shù)據(jù)帶來變異性，進而可能影響污染控制趨勢的準確性。人為采樣誤差或未遵循程序的情況可能包括壓力不一致、時間控制不當或缺乏無菌操作技術(shù)，從而導(dǎo)致數(shù)據(jù)無法可靠反映環(huán)境條件。    

這凸顯了全面培訓計劃的重要性——此類計劃需超越對程序的表面認知，重點培養(yǎng)表面采樣執(zhí)行的真正能力以及對微生物回收效果的責任感。相關(guān)能力必須確保分析人員理解采樣對象、檢測參數(shù)，以及其特定操作技術(shù)如何直接影響回收效率結(jié)果。對于所有公司而言，若表面確實存在污染，檢測到實際污染才是最符合利益的。盡管本文聚焦于表面采樣，但總體而言，培養(yǎng)皿的正確處理也是有活力空氣采樣和人員監(jiān)測的基礎(chǔ)。

Expectations around method understanding and performance are increasingly being discussed in regulatory and compendial guidance. For example, the current language in the FDA Aseptic Processing Guidance, EU GMP Annex 1, and USP chapters <797>, <1115> and <1116> all support the fundamental requirements that surface sampling methods should be well understood and appropriately controlled. While surface sampling is recognized as a semi-quantitative method with well-characterized limitations, industry efforts can still be made to improve its consistency and reliability. Standardizing the variables discussed in this article, where possible, can enhance the reproducibility of results and thus ensure recovery efficiency is optimized. Personnel qualification plays a critical role in minimizing method-related variability, and consistent training is key to achieving reliable outcomes.
監(jiān)管和藥典指南中對方法理解與性能的要求正成為越來越多的討論焦點。例如，美國FDA無菌工藝指南、歐盟GMP附件1以及USP通則<797>、<1115>和<1116>均支持以下基本要求：表面采樣方法應(yīng)被充分理解并得到適當控制。盡管表面采樣被公認為是一種具有明確局限性的半定量方法，但行業(yè)仍可致力于提高其一致性和可靠性。在可能的范圍內(nèi)對本文討論的變量進行標準化，可增強結(jié)果的可重復(fù)性，從而確?；厥招蔬_到最優(yōu)。人員資質(zhì)認證在最大限度減少方法相關(guān)變異性方面發(fā)揮關(guān)鍵作用，而持續(xù)一致的培訓則是實現(xiàn)可靠結(jié)果的核心。

A path forward includes the development of structured, competency-based qualification programs for personnel who perform viable surface sampling. These programs should include hands-on instruction with established methods, initial and periodic assessment of the sampler’s skills, and clear procedural guidance that defines essential method parameters such as contact time, applied pressure, and aseptic handling. Ultimately, strengthening personnel training and qualification presents an opportunity to reinforce confidence in the manual microbiological methods widely used in pharmaceutical manufacturing. It is unlikely that current surface sampling methods will be fully replaced by more modern alternatives soon, making a focus on consistency and competency all the more important. Continued investment in education, targeted training, and personnel qualification, particularly when linked to recovery efficiency performance, can help reduce variability and enhance the reliability of microbial surface sampling data in controlled environments.
未來的發(fā)展路徑包括為執(zhí)行有活力表面采樣的人員制定結(jié)構(gòu)化、基于能力的資質(zhì)認證計劃。這些計劃應(yīng)包含以下內(nèi)容：

- 采用既定方法的實操指導(dǎo)；   

- 對采樣人員技能的初始和定期評估；   

- 明確界定關(guān)鍵方法參數(shù)（如接觸時間、施加壓力、無菌操作）的程序性指南。 

 歸根結(jié)底，加強人員培訓與資質(zhì)認證有助于增強對制藥生產(chǎn)中廣泛使用的手動微生物采樣方法的信心。當前的表面采樣方法短期內(nèi)不太可能被更現(xiàn)代化的替代方案完全取代，因此，關(guān)注操作一致性和人員能力尤為重要。持續(xù)投資于教育、針對性培訓和人員資質(zhì)認證（尤其是將其與回收效率表現(xiàn)掛鉤時），有助于減少變異性，提升受控環(huán)境中微生物表面采樣數(shù)據(jù)的可靠性。

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